Zodiac Legacy LRZ User manual

INSTALLATION AND
OPERATION MANUAL
ENGLISH
WARNING
FOR YOUR SAFETY: This product must be installed and serviced by a contractor who is gas safe registered and
HWB1 certified. Before installing this product, read and follow all warning notices and instructions that accompany
this product. Failure to follow warning notices and instructions may result in property damage, personal injury, or
death. Improper installation and/or operation can create carbon monoxide gas and flue gases which can cause
serious injury, property damage, or death. For indoor installations, as an additional measure of safety, Zodiac
Pool Systems, Inc. strongly recommends installation of suitable Carbon Monoxide detectors in the vicinity of this
appliance and in any adjacent occupied spaces. Improper installation and/or operation will void the warranty.
If these instructions are not followed exactly, a fire or explosion may result,
causing property damage, personal injury, or death.
H0316500 Rev F
WARNING
The GAS SAFETY (INSTALLATION AND USE) REGULATIONS 1998 as amended, place statutory requirements
on gas users.
This heater is certified to European requirements for use only as a swimming pool or spa heater. The heater must
not be used for any other purpose and must be installed and serviced by a qualified professional. The heater must
be operated strictly in accordance with the user's instructions and applicable laws.
If the heater is installed in a room, it must be separated from a living space, and adequate air supply and
ventilation must be provided and maintained.
Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance.
Read this manual in its entirety. If these instructions are not followed exactly,
a fire or explosion may result, causing property damage, personal injury, or death.
Installation and
Operation Manual
Legacy™
Pool and Spa Heater
Model LRZ Millivolt
Natural Gas or LPG

Page 3
ENGLISH
Installation and Operation Manual |Legacy™ Model LRZM Pool/Spa Heater
Section 1. General Information .................... 5
1.1 Introduction.................................................... 5
1.2 Consumer Information and Safety................. 5
1.2.1 Spa/Hot Tub Safety Rules ........................ 5
1.2.2 Swimming Pool Energy Saving
Tips ........................................................... 6
1.3 Warranty ........................................................ 6
1.4 Codes and Standards.................................... 6
1.5 Technical Assistance ..................................... 6
1.6 Materials Installer Must Provide .................... 6
1.6.1 Materials for All Applications..................... 6
1.6.2 Materials for Special Applications............. 6
1.7 Specications ................................................ 7
1.7.1 GeneralSpecications.............................. 7
1.7.2 PerformanceSpecications...................... 7
1.7.3 Dimensions............................................... 7
Section 2. Installation Instructions.............. 7
2.1 Introduction.................................................... 7
2.2. Statutory Information ..................................... 8
2.3 General Installation Requirements ................ 9
2.4 Field Assembly ............................................. 9
2.5 Location Requirements ................................. 9
2.5.1 Introduction............................................... 9
2.5.2 Clearances ............................................... 9
2.5.3 Flooring..................................................... 10
2.5.4 Outdoor Installation .................................. 10
2.5.5 Indoor for Natural Gas Installation
Only .......................................................... 11
Section 3. Venting.......................................... 11
3.1 Combustion Air Supply .................................. 11
3.2 Flue System Type B11 (Indoor)..................... 11
3.3 Vent Pipe Sizing and General Installation .... 12
3.3.1 Outdoor Installations................................. 12
3.3.2 Indoor Installations (Natural Gas ONLY) .. 12
3.3.3 Inspection and Replacement of Existing
Vent System with New Components ........ 13
Section 4. Gas Connections......................... 13
4.1 Gas Supply and Piping.................................. 13
4.2 Burner Pressure ............................................ 14
4.3 Special Precautions for LPG ......................... 14
Section 5. Water Connections...................... 14
5.1 Water Piping .................................................. 14
5.2 Hydraulic Head Loss ..................................... 14
5.3 Check Valve Installation ................................ 14
5.4 Automatic Flow Control Valve ....................... 14
5.5 Reversible Water Connections ...................... 15
5.6 Connections at Heater................................... 17
5.7 Pressure Relief Valve .................................... 17
5.8 Auxiliary Components, Chlorinators, Ozone
Generators, and Sanitizing Chemicals .......... 19
Section 6. Electrical....................................... 19
6.1 Main Power ................................................... 19
6.2 Earth Bonding................................................ 19
6.3 Auxiliary Time Clock Wiring........................... 20
Section 7. Commissioning............................ 21
7.1 Heater Start-Up ............................................. 21
Section 8. Operating Instructions................ 21
8.1 Normal Operation .......................................... 21
8.2 Start-Up ......................................................... 22
8.3 Lighting and Shutdown Procedures .............. 22
8.3.1 Lighting the Heater ................................... 22
8.3.2 Relighting the Heater................................ 24
8.3.3 Shut-Down Procedure .............................. 24
8.4 Turning the Heater On/Off and
Setting the Temperature Control ................... 24
Section 9. Maintenance................................. 25
9.1 Water Chemistry............................................ 25
9.2 Seasonal Care............................................... 25
9.2.1 Spring and Fall Operation......................... 25
9.2.2 Winterizing................................................ 25
9.2.3 Spring Start-up ......................................... 26
9.3 Inspection and Service .................................. 26
9.3.1 Owner Inspection...................................... 26
9.3.2 Professional Inspection ............................ 26
Section 10. Troubleshooting ........................ 28
10.1 General Heater Troubleshooting ................... 28
Table of Contents

Page 4 ENGLISH Legacy™ Model LRZM Pool/Spa Heater |Installation and Operation Manual
Section 11. Professional
Maintenance and Service........ 30
11.1 General Information....................................... 30
11.2 Natural-Draft Combustion System................. 30
11.3 Heater Components and Their Operation ..... 30
11.4 Electrical Troubleshooting ............................. 31
11.4.1 Gas Valve ................................................. 31
11.4.2 Pilot Generator ......................................... 33
11.4.3 Fusible Link .............................................. 33
11.4.4 Fireman Switch and External ...................
Interlocks .................................................. 33
11.4.5 Limit Switches........................................... 34
11.4.6 Water Pressure Switch ............................. 34
11.4.7 Temperature Control Circuit...................... 34
11.4.7.1 ON/OFF Toggle Switch ..................... 34
11.5 Adjusting the Water Pressure Switch ............ 35
11.6 Temperature Rise .......................................... 35
Section 12. Replacement Parts .................... 36
12.1 Ordering Information ..................................... 36
12.2 Parts List ....................................................... 37
12.3 General Exploded View................................. 38
12.4 Detailed Exploded View ................................ 39
Table of Contents (Continued)

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ENGLISH
Installation and Operation Manual |Legacy™ Model LRZM Pool/Spa Heater
Section 1. General Information
1.1 Introduction
This manual provides installation and operation
instructions for the Legacy Model LRZ millivolt pool
and spa heaters. Read these installation and operation
instructions completely before proceeding with the
installation. The installation must be conducted by a
qualied professional. While the entire manual should
be read by both the qualied professional installer
and the user, Sections 2 through 7 of this manual are
intended for the qualied professional installer. The
Operating instructions for the user begin in Section 8.
Consult the Zodiac factory, or local factory representa-
tive, with any questions regarding this equipment. The
instructions cover two (2) types of heaters as follows:
1. Type A (ueless) for outdoor installations only.
2. Type B11 ue for outdoor and indoor installations,
but must not be installed in a living space.
The Legacy model LRZ millivolt heater is a self
contained standing pilot unit and requires no external
power.
The Legacy Model LRZ millivolt heater
is specically designed for heating fresh water
swimming pools and spas, and with proper installation
and care, will provide years of reliable service. Do not
use the heater to maintain pool or spa water tempera-
ture below 21°C (70°F). Do not use it as a heating
boiler or general service water heater. Consult your
dealer for the appropriate Zodiac products for these
applications.
NOTE “Fresh water swimming pools and spas”
include systems that utilize saltwater chlorine
generator units, such as the Jandy AquaPure®
Electronic Chlorine Generator. Please ensure
that the salt content of the pool/spa does not
exceed4000ppmandwaterowrateiswithin
110-470 lpm.
1.2 Consumer Information and Safety
The Legacy Model LRZ millivolt heater is
designed and manufactured to provide many years of
safe and reliable service when installed, operated and
maintained according to the information in this manual
and the installation codes referred to in later sections.
Throughout the manual safety warnings and cautions
are identied by the " " symbol. Be sure to read and
comply with all of the warnings and cautions.
1.2.1 Spa/Hot Tub Safety Rules
WARNING
Elevated water temperature can be hazardous.
Consult heater operation and installation instruc-
tions for water temperature guidelines before setting
temperature.
1. Spa or hot tub water temperature should never
exceed 40°C (104°F). Thirty-eight degrees
Celsius (38°C [100°F]) is considered safe for a
healthy adult. Special caution is recommended
for young children.
2. The drinking of alcoholic beverages before or
during spa or hot tub use can cause drowsiness
which could lead to unconsciousness, and subse-
quently result in drowning.
3. Pregnant women take note! Soaking in water
above 38.5°C (102°F) can cause fetal damage
during the rst three (3) months of pregnancy
(which could result in the birth of a brain-
damaged or deformed child). If pregnant women
are going to use a spa or hot tub, they should
make sure the water temperature is below 38°C
(100°F) maximum.
4. The water temperature should always be checked
with an accurate thermometer before entering a
spa or hot tub. Temperature controls may vary by
as much as 1°C (1°F).
5. Persons with a medical history of heart disease,
diabetes, circulatory or blood pressure problems
should consult their physician before using a hot
tub or spa.
6. Persons taking any medication which induces
drowsiness (e.g., tranquilizers, antihistamines, or
anticoagulants) should not use spas or hot tubs.
7. This appliance is not intended for use by persons
(including children) with reduced physical,
sensory or mental capabilities, or lack of experi-
ence and knowledge, unless they have been given
supervision or instruction concerning use of
appliance by a person responsible for their safety.
Children should be supervised to ensure that they
do not play with the appliance.
8. Prolonged immersion in hot water can induce
hyperthermia.
Hyperthermia occurs when the internal body
temperature reaches a level several degrees above the
normal body temperature of 37°C (98.6°F). Symptoms
include dizziness, fainting, drowsiness, lethargy, and
an increase in the internal body temperature. The
effects of hyperthermia include:
• Lack of awareness of impending hazard
• Failure to perceive heat
• Failure to recognize need to leave spa
• Physical inability to leave spa
• Fetal damage in pregnant women
• Unconsciousness resulting in a danger of
drowning

Page 6 ENGLISH Legacy™ Model LRZM Pool/Spa Heater |Installation and Operation Manual
1.2.2 Swimming Pool Energy Saving
Tips
Zodiac Pool Systems, Inc., ("Zodiac") offers the
following recommendations to help conserve fuel
and minimize the cost of operating your pool heater
without sacricing comfort.
1. The American Red Cross recommends a
maximum water temperature of 25°C (78°F).
Use an accurate pool thermometer. A difference
of 2°C (4°F), between 26°C and 28°C (78°F and
82°F), will use as much as 40% more gas.
2. Carefully monitor the water temperature of your
pool in the summertime. You can reduce heater
usage due to warmer air temperatures.
3. Find the proper setting on the pool heater temper-
ature control and use the Set Point Lockout
feature to discourage further adjustments.
4. Set the pump time clock to start the pump no
earlier than 6:00 AM during the pool heating
season. This is the time when nightly heat loss
balances.
5. If the pool is only going to be used on weekends,
reduce the heater temperature control setting by
8 or 10 degrees during the week. Reset it to the
25°C (78°F) level a day or so before you plan to
use the pool.
6. During the winter or when on vacation for longer
than a week, shut down the heater by following
the shutdown instructions found on the inside of
the heater.
7. Where possible, shelter the pool from prevail-
ing winds with well-trimmed hedges or other
landscaping, cabanas, or fencing.
8. Always use a pool cover when practical. Besides
providing a valuable safety feature, a pool cover
will reduce heat loss, conserve chemicals, and
reduce the load on lter systems.
1.3 Warranty
The Legacy Model LRZ millivolt heater is sold
with a limited factory warranty. Details are specied
on the back cover of this manual.
Make all warranty claims to an authorized Zodiac
representative or directly to the factory. Claims must
include the heater serial number and model (this infor-
mation can be found on the rating plate), installation
date, and name of the installer. Shipping costs are not
included in the warranty coverage.
The warranty does NOT cover damage caused
by improper assembly, installation, operation or eld
modication. Also, damage to the heat exchanger by
corrosive water is NOT covered by the warranty. See
Section 9.1 for maintaining proper pool water
chemistry.
NOTE Keep this manual in a safe place for future
reference when inspecting or servicing the heater.
1.4 Codes and Standards
The Legacy Model LRZ millivolt heater has
been tested and certied by GL Industrial Services for
compliance with the Gas Appliance Directive (GAD;
2009/142/EC) and the latest version of European
Standard, BSEN 656. In addition, the product has
also been found to be in compliance with the essen-
tial requirements of the Low Voltage Directive (LVD;
2006/95/EC), and the Electromagnetic Compatibility
Directive (EMC Directive; 2004/108/EC).
All Zodiac heaters must be installed in accor-
dance with the local building and installation codes as
per the utility or authorities having jurisdiction.
Any changes to the heater, gas controls, gas
orices, wiring, draft hood, vent cap, or improper
installation may void the warranty. If change is
required to any of the above, consult the factory.
1.5 Technical Assistance
Consult your local Zodiac distributor with any
questions or problems involving the specications,
installation, and operation of your Zodiac equipment.
1.6 Materials Installer Must Provide
1.6.1 Materials for All Applications
The following items are needed and are to be
supplied by the installer for all Legacy Model LRZ
millivolt heater installations:
1. The correct size gas pipe to supply gas from the
meter to the heater (see Section 4.1).
2. A manually operated gas cock to be installed in
the gas line outside of the heater jacket.
3. Plumbing items needed to provide a sediment
trap (drip leg) in the gas line between the manual
gas cock and the heater (see Section 4.1).
1.6.2 Materials for Special
Applications
In addition to the items listed above, the follow-
ing items are needed for special applications:
1. A factory authorized draft hood and any vent
pipe needed for indoor installations. See Section
3.3.2. Draft hoods are available from any Zodiac
distributor.
2. Primer and cement suitable for cementing PVC
pipe to the CPVC Zodiac unions supplied with
the heater.

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Installation and Operation Manual |Legacy™ Model LRZM Pool/Spa Heater
3. A noncombustible platform for installation
on combustible surfaces (see Section 2.5.3).
Noncombustible bases are available from your
Zodiac distributor.
4. A factory approved vent cap for all outdoor
installations where wind conditions may cause
downdrafting. Approved vent caps are available
from your Zodiac distributor. See Section 12.2,
"Parts List", of this manual for the correct part
number.
1.7 Specications
1.7.1 GeneralSpecications
1. Installation Location:
Certied for use:
Natural Gas: Indoor and Outdoor
LPG: Outdoor Only
Refer to Table 1.
2. Minimum Clearance From Combustible Material
See Table 4.
1.7.2 PerformanceSpecications
The Legacy Model LRZ millivolt heater perfor-
mance specications are shown in Table 2.
1.7.3 Dimensions
See Figure 1 for a diagram showing the heater's
exterior dimensions and dimensions to critical connec-
tions on the heater.
Section 2. Installation Instructions
2.1 Introduction
WARNING
This product must be installed and serviced by a
contractorwhoislicensedandqualiedinpool
equipment. Improper installation or maintenance
can cause nausea or asphyxiation from carbon
monoxideinuegaseswhichcouldresultinsevere
injury, or death. For indoor installations, as an ad-
ditional measure of safety, Zodiac strongly recom-
mends installation of suitable Carbon Monoxide
detectors in the vicinity of this appliance and in any
adjacent occupied spaces. The heater may only be
installed in a room which complies with the appro-
priate ventilation requirements and which is sepa-
rate from living areas.
Install the Legacy Model LRZ millivolt heater,
vent caps and draft hoods in accordance with the
procedures in this manual, local codes and ordinances,
and in accordance with the latest edition of the appro-
priate national code (see Section 1.4 "Codes and
Standards").
All gas-red products require correct installation
to assure safe operation. The requirements for pool
heaters include the following:
1. Field assembly (if required)
2. Appropriate site location (clearances) and ooring
3. Sufcient combustion and ventilation air
4. Properly sized gas meter and piping
Table1.GeneralSpecications
LRZ
125 175 250 325 400
Water Capacity (L) 0,81 0,95 1,16 1,35 1,57
Minimum Water Flow (l/min) 75,7 75,7 94,6 113,6 113,6
Maximum Static Head (bar) 5,1 5,1 5,1 5,1 5,1
Maximum Outlet Temp (C) 40 40 40 40 40
Dry Weight (kg) 60 67 78 88 100
Gas Connection 3/4 in Bsp
(Rc 3/4)
3/4 in Bsp
(Rc 3/4)
3/4 in Bsp
(Rc 3/4)
3/4 in Bsp
(Rc 3/4)
3/4 in Bsp
(Rc 3/4)
Water Inlet Connection 2" unthreaded PVC
or CPVC
2" unthreaded PVC
or CPVC
2" unthreaded PVC
or CPVC
2" unthreaded PVC
or CPVC
2" unthreaded PVC
or CPVC
Water Outlet Connection 2" unthreaded PVC
or CPVC
2" unthreaded PVC
or CPVC
2" unthreaded PVC
or CPVC
2" unthreaded PVC
or CPVC
2" unthreaded PVC
or CPVC
Electrical Supply 220-240VAC, 50 Hz,
5 Amps Max
220-240VAC, 50 Hz,
5 Amps Max
220-240VAC, 50 Hz,
5 Amps Max
220-240VAC, 50 Hz,
5 Amps Max
220-240VAC, 50 Hz,
5 Amps Max
IP Rating IPX4
Flue Types Flue Type A (Flueless) for Outdoor Installations Only
Flue Type B11 (with Vent Cap for High Wind Areas) For Outdoor Installation Only
Flue Type B11 (with Draft Hood) for Indoor Installation Only
Appliance Category:
Natural Gas I2H
LPG I3P
Inlet Pressure (mbar)
Natural Gas G20
LPG G31 @ 37 mbar
Note: The LPG heat inputs apply up to an altitude of 600 m. Above this altitude, de-rate the heat input by 4% for every 300 m.

Page 8 ENGLISH Legacy™ Model LRZM Pool/Spa Heater |Installation and Operation Manual
5. Proper electrical wiring (if required)
6. Adequate water ow
This manual provides the information needed to
meet these requirements. Review all application and
installation procedures completely before continuing
the installation.
2.2. Statutory Information
It is the law that all gas appliances are to be
installed only by competent persons (e.g., registered
members of Gas Safe) in accordance with the Gas
Safety (Installation and Use) Regulations, latest
published version of BS6798, BS5440 Pt. 1 and
Pt. 2, BS6891, and BS5482 Pt. 2. Failure to install
appliances correctly could lead to prosecution.
The Legacy heater, as supplied, has been tested
and certied by Gas Appliance Directive (GAD;
2009/142/EC) and the latest version of European
Standard, BSEN 656 for use with natural and LPG
gases. Legacy heaters are only permitted to be installed
in the open air or in a room which is separated from
living rooms and provided with appropriate ventilation
directly to the outside.
WARNING
TheLegacyheateriscertiedtoEuropeanrequire-
ments for use only as a swimming pool or spa
heater. The Legacy heater must not be used for any
other purpose and must be installed and serviced
byaqualiedprofessional.TheLegacyheatermust
be operated strictly in accordance with the manufac-
turer's instructions. If the Legacy heater is installed
in a room, adequate air supply and ventilation
must be provided and maintained. Never store any
materials within the area of the heater or ventilation
openings.
It is important that no external control devices
(e.g., ue dampers, economizers, etc.) be directly
connected to the Legacy heater unless covered by
these installation and servicing instructions or other-
Figure1. GeneralConguration
A194 mm
1000 mm
95 mm
264 mm
406 mm
127 mm 203 mm
724 mm
333 mm
H
1041 mm
Outdoor Flueless Heater Configuration Indoor Open Flue Configuration with Draft Hood
Outdoor Flue Configuration with Vent Cap
Model
Heater Width
Dim "A"
Venting Dimensions
Vent Diameter Outdoor
Dimension "H"
Indoor
Dimension "H"
mm mm mm mm
125 384 150 441 413
175 460 150 457 613
250 578 175 464 641
325 683 200 479 673
400 822 230 546 699

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Installation and Operation Manual |Legacy™ Model LRZM Pool/Spa Heater
wise recommended in writing by Zodiac, if in doubt
please ask. Any direct connection of a control device
not approved by Zodiac, could invalidate the Gas
Appliance Directive (GAD) certication, the normal
Legacy heater warranty, and could also violate appli-
cable gas safety regulations.
2.3 General Installation Requirements
The Legacy heater must be installed by compe-
tent persons (e.g., registered member of Safe Gas).
The Legacy heater must be installed in accordance
with the relevant requirements of the Gas Safety
Regulations, current I.E.E. Regulations, Model Water
Bylaws, local Water Authority Bylaws, and any
relevant requirements of local gas region, local author-
ity, and relevant British Standard Codes of Practice
and Building Regulations.
2.4 Field Assembly
The Legacy Model LRZ millivolt heater is
shipped from the factory with the top assembly in
the low-prole ueless Type A conguration for
outdoor installation. The Legacy Model LRZ millivolt
heater is design certied for indoor installation when
equipped with a draft hood and Type B11 ue, which
must be installed without modication.
Check the rating plate on the heater or the Parts
List (Section 12) of this manual for the correct Zodiac
draft hood or vent cap part number. See instructions
supplied with the draft hood or vent cap for instal-
lation and attachment. When the draft hood is used,
locate the heater so as to be in the same atmospheric
pressure zone as the combustion air inlet to the heater.
2.5 Location Requirements
2.5.1 Introduction
CAUTION
When pool equipment is located below the pool
surface, a leak from any component can cause
largescalewaterlossorooding.Zodiaccannotbe
responsibleforsuchwaterlossoroodingorresult-
ing damage.
The Legacy Model LRZ millivolt heater may
be installed indoors or outdoors as outlined in later
sections. Location of the heater below or above the
pool water level affects operation of its water pressure
switch. See sections on water piping and heater start-
up for more information about this.
Avoid placing the heater in locations where it can
cause damage by water or condensate leakage. If this
is not possible, provide a suitable drain pan to catch
and divert any leakage. The pan must not restrict the
air ow around the heater.
All criteria given in the following sections
reect minimum clearances as stated in the national
standards. However, each installation must also be
evaluated, taking into account the prevailing local
conditions such as wind speed and direction, proxim-
ity and height of walls that may block ventilation, and
proximity to public access areas.
2.5.2 Clearances
The heater must be placed to provide clearances
on all sides for maintenance and inspection. There
must also be minimum distances maintained from
combustible surfaces (see Table 3).
LRZ M Size (In BTU Input)
125 BTU 175 BTU 250 BTU 325 BTU 400 BTU
Nat.
Gas LPG Nat. Gas LPG Nat. Gas LPG Nat. Gas LPG Nat. Gas LPG
Heat Input Gross (kW) 40,7 40,7 56,9 56,9 81,5 81,5 105,9 105,9 130,3 130,3
Heat Input Net (kW) 36,7 36,7 51,3 51,3 73,4 73,4 95,4 95,4 117,4 117,4
Heat Output (kW) 28,6 28,6 41,1 41,1 58,7 58,7 76,8 76,8 95,1 95,1
Max. Burner Pressure
(mbar)
9 22,4 9 22,4 9 22,4 9 22,4 9 22,4
Gas Rate (m3/h) G20 3,5 -- 4.9 -- 7 -- 9,1 -- 11,2 --
Gas Rate (m3/h) G30 -- 1,05 -- 1,48 -- 2,3 -- 2,99 -- 3,47
Flue Gas Volume
4.5% CO2, 120C (l/sec) 32,1 -- 44,9 -- 64,1 -- 83,9 -- 102,8 --
Flue Gas Volume
4.5% CO2, 120C (l/sec)
G30 -- 32,3 -- 45,3 -- 70,3 -- 91,4 -- 106,4
Injector Diameter (mm
and marking)
(2,26)
Marked
43
(1,51)
Marked
53
(2,26)
Marked
43
(1,51)
Marked
53
(2,26)
Marked
43
(1,51)
Marked
53
(2,26)
Marked
43
(1,51)
Marked
53
(2,26)
Marked
43
(1,51)
Marked
53
Table2.LRZMPerformanceSpecications

Page 10 ENGLISH Legacy™ Model LRZM Pool/Spa Heater |Installation and Operation Manual
At least 457 mm access must be available in
front of the heater for burner removal and access to the
igniter.
If the heater is to be installed in a garage, or
similar structure, all burners and burner ignition
devices must have a minimum 457 mm clearance
above the oor.
This heater must be installed at least 1.52 m from
the inside wall of a pool unless the heater is separated
from the pool by a solid fence, wall or other permanent
solid barrier.
2.5.3 Flooring
The heater must be installed on a level surface
of noncombustible construction or on re-resistant
slabs or arches. Noncombustible ooring is dened
as ooring material and surface nish not capable of
being ignited and burning and with no combustible
materials against the underside. Acceptable materials
are those consisting entirely of a combination of steel,
iron, brick, tile, concrete, slate, glass or plaster. Do not
install the heater directly on a combustible wood or
carpet oor without placing a noncombustible platform
between the oor and the heater.
The heater can be installed on a combustible oor
if a noncombustible base assembly, available from
Zodiac, is used. See the heater rating plate or the Parts
List (Section 12) of this manual for the appropriate
base part number. Heaters must never be installed
directly on carpeting.
As an alternative to the Zodiac noncombustible
base plate, the heater may be placed on a combustible
surface when there is a platform under the heater made
of hollow masonry no less than 102 mm thick, covered
with sheet metal at least 24 gauge thick and extend-
ing beyond the full width and depth of the heater by at
least 153 mm in all directions. The masonry must be
laid with ends unsealed, and joints matched to provide
free circulation of air from side to side through the
masonry (see Figure 2). If the heater is installed in a
carpeted alcove, the entire oor of the alcove must be
covered by a noncombustible panel.
2.5.4 Outdoor Installation
The Legacy Model LRZ millivolt heater can be
installed in the low-prole Type A ueless congu-
ration as received from the factory. Alternately, the
heater may be installed outdoors using a Type B11
vent cap. This vent cap is used in high wind installa-
tions. No draft hood is required for this type of outdoor
installation.
Locate the heater in an open, unroofed area. Do
not install the heater under a deck. Do not locate the
heater below or adjacent to any doors, glass openings,
louvers, grills, etc., which connect in any way with an
inhabited area of a building, even though the access
might be through another structure (e.g., a garage
or utility room). There must be a minimum of 2 m
horizontally or 2 m vertically between the heater and
any door, glass opening, or gravity inlet into a build-
ing. See Figure 3.
The top surface of the heater must be at least
0.91 m above any forced air inlet, or intake ducts
located within 3.0 m horizontally.
If the heater is installed under an overhang, there
must be a minimum clearance of 1.5 m above the top
of the heater and the structure should not overhang the
heater more than 0.30 m. The area under the overhang
must be open on three (3) sides. This prevents combus-
tion gases from being diverted into living areas
through doors, windows, or gravity inlets.
Figure 2. Noncombustible Platform
153mm
153mm
Notes:
1. Blocks must provide a solid base and be braced so they
cannot slip out of place.
2. Air openings in blocks must be arranged to provide un-
restricted opening through entire width or length of base.
3. Sheet metal must be at least 24 ga. and extend 153 mm
beyond the heater jacket on all sides.
Sheet Metal Min.
Thickness 24 Ga
Hollow Concrete
Block Platform
Table 3. Minimum Heater Clearances
From Combustible Surfaces
Note: Clearances listed in Table 4 are manufacturer's tested
values. These are given as minimum values. Where local
codes apply, and values are different than those listed in
Table 4, use the greater value to ensure safe operation.
SIDE OF HEATER MINIMUM CLEARANCE
Millimeters
BLANK 203
REAR 150
PIPING 355
TOP 1120
FRONT 457

Page 11
ENGLISH
Installation and Operation Manual |Legacy™ Model LRZM Pool/Spa Heater
If the heater is installed close to a structure,
protect it from rain water runoff with rain gutters on
the roof or other measures. Do not locate the heater
near irrigation sprinkler systems that could spray water
on it. Water from sprinklers may cause damage to
controls and electronic components.
Avoid locations where wind deection off nearby
structures might cause downdraft conditions. Where
downdraft conditions exist, locate the heater at least
0.91 m from vertical surfaces (e.g., nearby buildings
and walls).
2.5.5 Indoor for Natural Gas
Installation Only
The Legacy heater can be installed indoors using
the draft diverter available from Zodiac, and a Type
B11 ue system complying with the national and
local applicable standards in addition to the Building
Regulations (see Section 2).
Section 3. Venting
The applicable codes, standards and Zodiac,
require that the heater be properly vented as outlined
in this manual. Proper ventilation of exhaust and
combustion air are essential for the safe and efcient
operation of the heater.
3.1 Combustion Air Supply
The heater location must provide sufcient air
supply for proper combustion and ventilation of the
surrounding area.
In general, the room in which a heater is installed
should be provided with two (2) permanent air supply
openings; one within 305 mm of the ceiling, the other
within 305 mm of the oor. All indoor installations
must have uninterrupted openings to outside air for
combustion, ventilation, and dilution of ue gases
from inside the building (see Figure 4 and Table 4).
Zodiac, does not recommend indoor installations that
do not provide combustion air from outside the build-
ing.
Figure 3. Outdoor Heater Installation
Table 4. Ventilation Requirements
Positions of Air Vents Air Vent Areas
(Air Direct From Outside)
High Level 270 cm2plus 2.25 cm2per kW in
excess of 60 kW total rated input
Low Level 540 cm2plus 4.5 cm2per kW in
excess of 60 kW total rated input
Exhaust Fans or Vents: Any equipment
which exhausts air from the room where the heater
is installed can deplete the combustion air supply or
reverse the natural draft action of the venting system.
This could cause ue products to accumulate in the
room. Additional air must be supplied to compensate
for such exhaust.
The information in Table 3 is not applicable in
installations where exhaust fans or blowers of any type
are used. Such installations must be designed by quali-
ed engineers.
The heater must be completely isolated and
protected from any source of corrosive chemical fumes
such as those emitted by trichlorethylene, perchloro-
ethylene, chlorine, etc.
WARNING
Do not store any chemicals, cleaners, or other cor-
rosive material near combustion air openings or in
the room. Avoid locating appliance vents in the vi-
cinity of combustion air openings. Failure to prevent
corrosive materials from mixing with combustion air
can result in reduced heater life and unsafe heater
operation.
3.2 Flue System Type B11 (Indoor)
Connect the draft diverter to a Type B11 ue
system of at least the same diameter, and end at least
0.6 meters above the highest point of the roof or other
object that is within 3.05 m of the vent. Install a certi-
ed terminal which allows a full equivalent opening
for ue products (see Figure 4). There must be at least
600 mm of vertical ue above the drafthood. Bends in
the ue should not exceed 45° to the vertical.
To make sure the heater operates safely and satis-
factorily, the ue system must be able to completely
remove combustion products at all times. The number
of bends and lengths of horizontal ue pipe used
should be kept to a minimum in order to reduce gas
ow resistance.
Compliance with all national and local applicable
installation codes and regulations should be strictly
observed.
The ue design should avoid the formation of
excessive quantities of condensate. For this reason, it
is recommended that all ues be insulated and lined.
For brick or similar structures, a stainless steel rigid
or exible ue liner (Grade 304/316) may be used in
conjunction with a 50 mm (minimum) thick layer or
2m
2m
2m

Page 12 ENGLISH Legacy™ Model LRZM Pool/Spa Heater |Installation and Operation Manual
vermiculite or perlite granules between the liner and
the inner skin of the chimney body.
Liners should be sealed at both top and bottom.
Drainage points should be provided at the bottom of
all vertical ue sections. Drain pipes should be:
1. No less than 25 mm inside diameter.
2. Made from acid condensate resistant material
(e.g., stainless steel).
3. Positioned so that pipe runs and discharge points
are not subject to the effects of frost and ue
gases cannot leak into the boiler room.
3.3 Vent Pipe Sizing and General
Installation
3.3.1 Outdoor Installations
For outdoor installations, exhaust venting consid-
erations will determine the placement of the heater
(See Section 2.5.4). If the heater cannot be placed so
as to meet the requirements stated in Section 2.5.4,
a Type B11 vent pipe and cap may be added to the
heater to move the exhaust vent opening to a position
that complies with the requirements. When the heater
is installed in areas of high wind or when unavoidably
installed near a vertical obstruction where downdraft-
ing may occur, it may be desirable to add a vent cap
directly to the top of the heater. In all cases, vent pipes
and caps must be of the same diameter as the exhaust
outlet of the heater. Approved vent caps may be
obtained through your Zodiac distributor.
3.3.2 Indoor Installations (Natural
Gas ONLY)
WARNING
Vent pipe diameter must be as required by appli-
cable local gas appliance installation codes such as
BS 5440. Undersized pipe can result in inadequate
venting and oversize pipe can result in vent conden-
sation. In either case the result can be release of
combustion products to the indoors. This can cause
serious injury or death by carbon monoxide poison-
ing or asphyxiation.
All indoor installations and outdoor shelter
installations require a factory approved draft hood and
Type B11 venting. The draft hood must be installed
without modication. All vent installations must be
made in accordance with all local, state or provincial
codes and with:
Avoid long horizontal runs of the vent pipe, and
90° elbows, reductions and restrictions. Horizontal
runs should have at least a 20 mm rise per meter in the
direction of ow.
Avoid terminating heater vents near air condi-
tioning or air supply fans. The fans can pick up
exhaust ue products from the heater and return them
inside the building, creating a possible health hazard.
Do not locate the vent terminal where ue
products could strike against building materials and
cause degradation.
Vent opening should be well away from trees
or other obstructions that would prevent free air ow
to and from vent terminal. Do not terminate the vent
under decks, stairways, or car ports.
Be sure to support all venting so that connec-
tions will not separate and so that the weight of the
vent pipe does not rest on the heater draft hood. All
connections should be made with rustproof sheet metal
screws. Do not weld or fasten the vent pipe to the
heater draft hood. The draft hood and heater top must
be easily removable for normal heater service and
inspection.
4)
AT LEAST
600 mm OF
VERTICAL
FLUE ABOVE
THE DRAFT
HOOD
DRAFT HOOD
BENDS
SHOULD NOT
EXCEED 45°
LISTED FLUE TERMINAL
NON-COMBUSTIBLE
BASE
VENT TERMINATED
AT LEAST 600 mm
ABOVE ANY OBJECT
WITHIN 3.1 m
3.1 m
6.35 mm
minimum pitch
per meter
of horizontal
pipe
Figure 4. Indoor Installation Venting or Outdoor Shelter Venting
NOTE
Use approved
roof jack.

Page 13
ENGLISH
Installation and Operation Manual |Legacy™ Model LRZM Pool/Spa Heater
such as "The Gas Safety (Installation and Use)
Regulations" (Statutory Instrument 1998 No.
2451).
2. Check the gas supply to be sure that it is the same
as the gas indicated on the heater's rating plate.
3. If there is any doubt regarding the capacity of
any existing service pipes or the size required
for new service pipes then the advice of the
gas supplier should be requested. Installation
pipework should be tted and tested for gas
soundness. Zodiac recommends the gas inlet pipe
sizes listed in Table 5.
4. Use the gures in Table 5 to size the gas inlet
piping from the gas meter to the heater. Check all
local codes for compliance before installing the
heater.
Table 5. Pipe Size Requirements*
Distance from Gas Meter
Heater
Size
0-15 m 15-30 m 30-60 m
mm mm mm
125 20 25 25
175 25 25 32
250 25 32 32
325 32 32 40
400 32 40 40
5. Before operating the heater, test for gas sound-
ness. Do not use a naked ame.
6. If the gas supply pressure is less than required,
check for undersized pipe between the meter and
the heater, a restrictive tting, or an undersized
gas meter. Gas supply pressures to the heater are
listed in Table 2.
The draft hood outlet is to be connected to an
unobstructed vent pipe of the same diameter, terminat-
ing outside the building. The vent must terminate at
least 0.6 m above the highest point of the roof or other
object that is within 3.05 m of the vent termination.
The vent pipe must have a listed vent cap which allows
a full equivalent opening for ue products (see Figure
4). The top of the vent cap must be at least ve (5) feet
in vertical height above the draft hood outlet.
Double wall or equivalent vent pipe is recom-
mended.
IMPORTANT NOTE: Do not use sheet metal screws at
the snap lock joints of gas vents.
When venting multiple appliances through one
common duct, each appliance must have its own vent
temperature limit switch. All vent limit switches must
be wired in series so as to prevent any appliance from
ring in the event of a blocked vent. Refer to national
and local installation codes for more information on
multiple venting.
3.3.3 Inspection and Replacement of
Existing Vent System with New
Components
If the Legacy heater is being installed to replace
an existing pool heater, it is recommended that a new
appropriate venting system be installed with the new
heater. However, if an existing venting system must be
used, be sure to carefully inspect the venting system to
ensure that it is in good condition and continues to be
appropriate for the Legacy heater. Replace any parts
that are not in good and serviceable condition with
new parts before completing the pool heater installa-
tion.
Section 4. Gas Connections
4.1 Gas Supply and Piping
Review the following general instructions before
continuing the installation.
WARNING
The Legacy Model LRZ pool and spa heaters are
designed for use with either natural gas or LPG.
Check the rating plate on the inner panel to be sure
that the heater is designed to use the type of gas
being supplied. DO NOT ATTEMPT TO CONVERT
THIS HEATER FOR USE WITH ANY OTHER
TYPE OF FUEL.
CAUTION
Permanent damage to the gas valve will occur if the
following procedures are not followed.
1. Gas piping installation must be in accordance
with all applicable local rules and regulations Figure 5. Fitting a Gas Service Cock
Gas Cock
Burner Pressure
Point
Inlet Gas Pressure
Test Port

Page 14 ENGLISH Legacy™ Model LRZM Pool/Spa Heater |Installation and Operation Manual
4.2 Burner Pressure
Conrm that gas supply pressure is correct. If
the gas supply pressure is less than required, check for
undersized pipe between the meter and the heater, a
restrictive tting, or an undersized gas meter. Gas inlet
pressures to the heater, when it is operating, are listed
in Table 2.
CAUTION
Burner gas pressure for the Legacy Model LRZ
natural gas heaters should be set to the values
listed in Table 2.
The burner pressure may be checked by connect-
ing a manometer to the pressure port on the burner.
Refer to Figure 5. The pressure will be zero when the
heater is not running. When the heater is operating the
burner gas pressure should be the values listed in
Table 2.
If the burner pressure indicated above is not
correct, check the gas train for possible problems.
Check the meter, gas line, gas ttings, and gas shut off
for under sizing. Check the gas valve inlet for excess
pipe dope, if all is correct, then it may be necessary to
adjust the gas valve regulator. To adjust the burner gas
pressure, rst remove the slotted cap next to the inlet
pressure port on the inlet side of the gas valve. Under
the slotted cap is a slotted plastic screw which increas-
es the burner pressure when turned clockwise and
decreases the burner pressure when turned counter-
clockwise. After measurements, and adjustments if
necessary, have been made, make sure to replace the
test point plugs on the inlet and burner pressure ports,
and the cap on the burner pressure adjustment screw.
It is extremely important to replace these parts before
leaving the installation. Failure to do so can result in
damage to property or injury or death. With the heater
ring, the pressure must be within the range shown in
Table 2. Also check the pressure with the heater off.
4.3 Special Precautions for LPG
LPG is heavier than air and can therefore more
readily collect or “pool” in enclosed areas if provision
for proper ventilation is not made. Installation of pool
heaters in enclosed areas such as pits is not recom-
mended.
Consult any local code and re protection author-
ities about specic installation restrictions in your area.
Section 5. Water Connections
5.1 Water Piping
Figure 6 illustrates typical piping for pool equip-
ment in pool/spa combination pools.
For normal installations, do not install a shutoff
valve or any kind of variable restriction in the water
piping between the heater outlet and the pool/spa. In
special installations where a shut-off valve, diverter
valve or other variable restriction is required in the
plumbing between the heater outlet and the pool,
Zodiac recommends the installation of a pressure relief
valve on the heater (see Section 5.7).
Arrangement of pool system components other
than as illustrated in these diagrams can affect the
operation of the heater’s water pressure switch.
Location of the heater above or below the pool water
surface can also affect operation of the switch. In
general, the pressure switch can be adjusted to accom-
modate this effect if the heater water connections
are no more than 1.8 m below the pool water surface
and no more than 4.5 m above it. See instructions for
pressure switch adjustment (Section 5.7) in the heater
start-up section of this manual for more information
about this.
Note that when pool equipment is located below
the pool surface a leak can result in large scale water
loss or ooding. Zodiac cannot be responsible for such
water loss or ooding or the damage caused by either
occurrence.
For special installations such as water connec-
tions below the water level of the pool, or for other
questions consult your local Zodiac dealer.
5.2 Hydraulic Head Loss
To verify that the minimum ows required
for the heater are met, a hydraulic head loss curve
is shown in Figure 7. This should be checked when
installing this heater into a new or existing piping
system. This should also be consulted when installing
a new pump.
5.3 Check Valve Installation
WARNING
A check valve can interfere with the proper
operation of certain Suction Vacuum Release
System (SVRS) products. To avoid possible en-
trapment hazard, serious injury, or death, make
sure to review the operation/owners manual of
your particular SVRS product before installing
the check valve.
The heater must be protected from back-siphon-
ing of water, which can result in dry starts. If there is
any chance of back-siphoning, provide a check valve
between the pool and the lter pump inlet.

Page 15
ENGLISH
Installation and Operation Manual |Legacy™ Model LRZM Pool/Spa Heater
LRZ Pressure Drop vs Flow
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
0 100 200 300 400 500
Water Flow (LPM)
Pressure Drop (m H2O)
LRZ125
LRZ250
LRZ175
LRZ325
LRZ400
5.5 Reversible Water Connections
The Legacy Model LRZ millivolt heater is
shipped with water connections on the right side,
but can be modied in the eld to provide left-side
water connections. This procedure involves remov-
ing the heat exchanger headers and reinstalling them
on opposite ends of the tube assembly. Some of the
heater wiring must be disconnected and re-routed, so
this procedure must be done only by a trained service
technician. Heat exchanger reversals are generally
done before the installation of power and water to the
heater. If you need to reverse the heat exchanger on
a previously installed heater be sure that all electri-
cal power, the gas supply and water supply have been
turned off before starting the procedure. These instruc-
tions have been written to include the steps needed
when reversing the water connections on an existing
installation. If you are reversing the headers on a new
installation, some steps will be ignored.
When an automatic chemical feeder is installed
in the plumbing, it must be installed downstream of
the heater (see Section 5.7). A check valve must be
installed between the heater and the chemical feeder to
prevent back-siphoning of chemically saturated water
into the heater where it will damage the components.
5.4 Automatic Flow Control Valve
The inlet/outlet header of the Legacy Model LRZ
millivolt heater comes equipped with an automatic
ow control valve. The automatic ow control valve
maintains the proper ow through the heater at rates
up to approximately 475 lpm. If the lter system ow
rate is higher than approximately 475 lpm, install a
manual bypass valve (see Figure 6), then perform a
temperature rise test (see Section 11.6) and adjust the
ow using the bypass valve until the proper tempera-
ture rise is obtained.
AQUAPURE
MANUAL BY-PASS DETAIL
MANUAL BY-PASS IS USED
WHEN FILTRATION RATE
EXCEEDS 125 GPM
Figure 6. Typical Piping Installation
Figure 7. Hydraulic Head Loss Curve

Page 16 ENGLISH Legacy™ Model LRZM Pool/Spa Heater |Installation and Operation Manual
Water connection reversal is illustrated in Figures
8 and 9. Proceed as follows:
1. For an existing installation, drain the heater by
removing the two (2) drain plugs on the inlet/
outlet header and the drain plug on the return
header.
2. Remove the heater front panel (door).
3. Remove the I/O header side cover plates, top and
bottom. See Figure 10.
4. Remove the return header side cover plates, top
and bottom. See Figure 10.
5. Tag and disconnect the black high limit wire
leading to the pressure switch (PS) and the black
wire on the Fireman's switch terminal which
leads to the high limit switch.
6. Remove the water temperature sensor nut from
the inlet/outlet header and remove the sensor.
7. Tag and disconnect the black and white wires
from the water pressure switch.
CAUTION
In order to prevent property damage or injury, en-
sure that the wiring is handled and routed carefully
so as not to cause any damage to it. Additionally, be
careful not to create any kinks in the water pressure
switch copper tubing when handling the header.
8. For an existing installation, remove the coupling
nuts from the header and disconnect the water
supply from the heater.
9. Remove the 10 bolts and washers from the inlet/
outlet header and remove the header from the
tube assembly.
10. Remove the 10 bolts and washers from the return
header and remove the header from the tube
assembly.
11. For an existing installation, remove the tube
gaskets and clean the header's mating surface of
any corrosion or debris. Replace the tube gaskets
with new ones. Do not use any metal tools on the
header surface. Scratches may compromise the
seal integrity.
WARNING
To avoid product failure which can cause property
damage, serious personal injury or death, install the
inlet/outlet header with the high limit devices on the
bottom.
REAR PANEL
TOP PANEL
LEFT SIDE PANEL
RETURN HEADER SIDE
COVER PLATES
TOP AND BOTTOM
FRONT PANEL
(DOOR)
CONTROL PANEL BASE
VENT TOP
RIGHT SIDE PANEL
IN/OUT HEADER
SIDE COVER PLATES
TOP AND BOTTOM
Figure10. LegacyPanelIdentication
Figure 8. Water Connections as Shipped
NOTE: When reversal
is complete the water
temperature sensor
wires and the syphon
loop tube will exit the
inlet/outlet header at
the back of the heater
and the drain plugs are
facing down. Bypass
Assembly
DO NOT
INTALL THE
INLET/OUTLET
HEADER
UPSIDE-DOWN
®
THE HIGH LIMIT
DEVICES MUST
BE ON THE
BOTTOM
Figure 9. Water Connections Reversed

Page 17
ENGLISH
Installation and Operation Manual |Legacy™ Model LRZM Pool/Spa Heater
12. Place the inlet/outlet header over the bolts and
gasketed tubes on the left side of the tube assem-
bly. Make sure the high limit devices are on the
bottom. Refer to Figure 9. Align the bolt and tube
holes in the header with the bolts and tubes in the
header bar and slide the assembly together.
13. Thread on the 10 bolts and washers and hand
tighten.
14. Place the return header over the bolts and gasket-
ed tubes on the right side of the tube assembly.
Align the bolt and tube holes in the header with
the bolts and tubes in the header bar and slide the
assembly together.
15. Thread on the 10 bolts and washers and hand
tighten.
16. Use a torque wrench to tighten the bolts on each
header to 4 ft-lbs. The bolts must be tightened in
the sequence indicated in Figure 11.
CAUTION
Failure to tighten the header as indicated in step 16
may cause the header to leak or become perma-
nently damaged from warping.
17. Remove the 3/4 inch button plug located in the
left side panel below the inlet/outlet header and
replace with the 3/4 inch wire grommet from
the right side panel below the return header.
The high limit leads were routed through this
grommet prior to removal in step 5. Install the
3/4 inch plug in the opening where the 3/4 inch
wire grommet was removed.
18. Reconnect the white wire on the pressure switch
(PS) and the white wire on the Fireman's switch
terminal.
19. Reinstall the temperature sensor in the inlet/
outlet header and tighten the nut.
20. Reconnect the black and white wires to the water
pressure switch.
46
510
1
8
732
9
Figure 11. Header Bolt Tightening Sequence Figure 12. Piping to Heater
O-RING
COUPLING
COUPLING
NUT
PVC OR CPVC PIPE
21. Use plastic wire ties to refasten the temperature
sensor, high limit switch and water pressure
switch wires to each other. Bundle the wires near
the control panel and fasten them with a wire tie.
CAUTION
In order to prevent property damage or injury, be
sure that none of the wires are in contact with a
sharp edge or a hot surface.
22. Install the return header side cover plate on the
right side of the unit.
23. Install the I/O header side cover plates, top and
bottom on the left side of the unit.
24. Replace the front panel (door).
5.6 Connections at Heater
The Legacy Model LRZ millivolt heater has a
standard 2 inch water header and coupling design.
With this feature, only nominal 2 inch PVC or CPVC
may be connected to the heater. However, by installing
the appropriate pipe adapters and two (2) short pieces
of 2 inch plastic pipe (supplied by the installer), any
size existing pipe may be tted to the heater.
To connect a section of 2 inch PVC or CPVC
pipe to the heater, rst slip a coupling nut onto the
pipe. Then prepare the end of the pipe with the proper
PVC/CPVC primer and glue. Follow the manufac-
turer’s instructions provided with the primer and glue
for preparation procedures and curing times. Apply
the slip-t side of the coupling to the end of the pipe.
Allow the glue to cure completely. Set the o-ring
into the groove on the face of the coupling. Slide the
coupling nut up to the coupling and tighten it to the
threaded connection on the header (see Figure 12).
5.7 Pressure Relief Valve
A pressure relief valve (PRV) is recommended in
all installations, and is mandatory in any installation
in which the water ow can be shut off between the
heater outlet and the pool/spa.
A pressure relief valve is not supplied with the
Legacy Model LRZ millivolt heater. However, it is
recommended that a pressure relief valve be installed
and may even be required by local codes.

Page 18 ENGLISH Legacy™ Model LRZM Pool/Spa Heater |Installation and Operation Manual
CAUTION
Do not use any pipe compound or pipe dope on
the threads of the adapter or any part that comes in
contact with the plastic headers. These compounds
may damage the header over a period of time.
CAUTION
In order to prevent property damage, do not over-
tighten. Overtightening may crack the header.
DO NOT TIGHTEN WITH A WRENCH.
Overtightening may crack the header. Route the
discharge piping so that discharge from the pipe does
not endanger anyone near the heater.
Be sure to check any applicable installation codes
in your area to determine whether a pressure relief
valve is required. See Section 12.2 (Parts List) of this
manual for the appropriate kit part number.
The pressure rating of the valve should be at or
below the lowest working pressure of any component
in the system. The maximum working pressure of this
heater is 5.1 bar.
Follow these steps to install a pressure relief valve:
1. To protect the threads while drilling, screw the
brass adapter (included with the Zodiac PRV
kit) into the blind threaded hole on the top of the
inlet/outlet header.
2. Using the countersink in the center of the blind
hole as a guide, drill a 6.4 mm (1/4 inch) hole
through the plastic (see Figure 13).
3. Open the hole by reaming it with a 9.5 mm (3/8
inch) drill bit.
4. Open the hole again by reaming it with a 12.7
mm (1/2 inch) drill bit.
CAUTION
Initially drilling a 12.7 mm (1/2 inch) hole without
reaming may cause the bit to "grab" on the plas-
tic. This may cause personal injury or damage the
plastic header.
5. Remove the brass adapter and clean the cuttings
out of the hole.
6. Install the rubber washer at the bottom of the
hole (see Figure 14).
7. Thread the adapter into the hole and tighten so
that it seals against the rubber washer.
8. With a permanent marker, place a mark on the
adapter so that the mark faces the same direction
as the water connections on the header.
9. Remove the adapter from the hole.
10. Coat the threads of the pressure relief valve
(PRV) with an appropriate metal to metal thread
sealant.
11. Install the adapter on the PRV and tighten using
two (2) wrenches. Use the mark made earlier on
the adapter to orient the PRV to the desired direc-
tion in relation to the water connections on the
header.
12. Reinstall the adapter, with the PRV, into the
plastic threaded hole and tighten it until the mark
on the adapter is once again facing the same
direction as the water connections on the header.
Figure 13. Drill Hole for Pressure Relief Valve
TEMPORARILY INSTALL
BRASS ADAPTER TO
PROTECT PLASTIC
THREADS
START WITH A 1/4" BIT
THEN OPEN HOLE WITH
A 3/8" BIT THEN OPEN
HOLE WITH A 1/2" BIT
Figure 14. Pressure Relief Valve Installation
RUBBER WASHER
BRASS ADAPTER
PRESSURE RELIEF
VALVE HAND
TIGHTEN ONLY

Page 19
ENGLISH
Installation and Operation Manual |Legacy™ Model LRZM Pool/Spa Heater
Refer to your local installation codes for more
detailed information. The valve setting should be
at or below the maximum working pressure of any
component in the lter system. The maximum working
pressure of the Legacy Model LRZ millivolt heater is
5.1 bar.
5.8 Auxiliary Components,
Chlorinators, Ozone Generators,
and Sanitizing Chemicals
The Legacy Model LRZ millivolt heater is
manufactured with materials that are not compatible
with high concentrations of ozone, chlorine, bromine,
or other sanitizing chemicals. Heater damage caused
by excessive chemicals or improper ozonization is not
covered by the Zodiac warranty. Be sure to adhere to
the following:
• When ozone is injected upstream of the heater,
install an offgas mixing chamber, or an ozone
bypass system between the heater and the ozone
injector to prevent ozone and air from entering
the heater.
• When chemical feeders are used, plumb the
feeder downstream of the heater and install
an in-line check valve between the heater and
the feeder (a minimum of 450 mm is required
between the heater and the check valve).
• Wire any electrical chemical feeder so that it
cannot operate unless the lter pump is running.
If the feeder has an independent clock control,
synchronize it with the lter clock.
• Never deposit chemicals directly in the pool
skimmer.
Section 6. Electrical
WARNING
This product must be installed and serviced by a
contractorwhoislicensedandqualiedinpool
equipment by the jurisdiction in which the product
will be installed where such state or local require-
ments exists. In the event no such state or local
requirement exists, the installer or maintainer must
beaprofessionalwithsufcientexperienceinpool
equipment installation and maintenance so that all
of the instructions in this manual can be followed
exactly. Before installing this product, read and fol-
low all warning notices and instructions that accom-
pany this product. Failure to follow warning notices
and instructions may result in property damage,
personal injury, or death.
CAUTION
Label all wires prior to disconnection when servic-
ing controls. Wiring errors can cause improper and
dangerous operation. Verify proper operation after
servicing.
6.1 Main Power
The Legacy heater does not require an external
source of electrical power to operate. The power for
the gas valve and safety circuit are generated by a
thermopile. The thermopile generates a millivolt signal
when heated by the pilot ame. Figure 15 shows the
internal electrical wiring diagram and schematic of the
heater.
6.2 Earth Bonding
CAUTION
To prevent premature failure of the appliance result-
ing from stray voltages and voltage differentials, the
heater must be bonded to other equipment which is
part of the pool plumbing system with a solid copper
wire not smaller in diameter than 8 AWG (10mm2).
Zodiac requires that the appliance be connected
to an "earth bonding loop" that includes all electrical
equipment in the system and on the equipment pad.
Earth bonding lugs must be connected with a solid
copper wire not smaller than 8 AWG (10mm2). Failure
to do so will void warranty.
Additionally, all metallic components of a pool
structure, including reinforcing steel, metal ttings
and above ground components be bonded together
(forming an “earth bonding grid”) with a solid copper
conductor not smaller than a 8 AWG (10mm2).

Page 20 ENGLISH Legacy™ Model LRZM Pool/Spa Heater |Installation and Operation Manual
The equipment and/or appliances associated
with the pool water circulating system, including, but
not limited to, pump motors and heaters must also be
bonded together as part of the equipotential bonding
grid. Zodiac provides a special labeled earth bonding
lug on the right side of the heater to accommodate this
requirement. Consult your local applicable installation
codes/regulations for additional requirements that may
apply.
6.3 Auxiliary Time Clock Wiring
If you install a time clock to control the lter
pump operation, it is recommended that the time clock
have its own low voltage (Fireman’s) switch to turn
off the heater before turning off the pump. The switch
should shut off the heater about 15 minutes before
the lter pump shuts off. This will allow for a more
efcient operation by removing any residual heat
contained in the heat exchanger back to the pool.
To install a time clock auxiliary switch into the
heater wires (see Figure 16):
1. Remove heater door.
2. Remove the factory installed wire between termi-
nals 1 and 2 on the terminal strip (see Figure 16).
3. Connect the wires from the time clock auxiliary
switch to the two (2) terminals. Use 14 AWG (2,5
mm2) stranded copper wire with a temperature
rating of 105°C (221°F) or greater.
The length of the wire between the heater and
the time clock should not exceed 4.57 m. The contact
points of the time clock switch should be silver, or a
low resistance alloy.
OR CONTROL
BLACK BLACK
ROLL-OUT SWITCH
(VENT FUSIBLE LINK) VENT TEMPERATURE LIMIT
Figure 16. Time Clock Wiring or Control Connection
Figure 15. Legacy Wiring Diagram
TEMPERATURE
CONTROL
ROLL-OUT SWITCH
(FUSIBLE LINK)
FIREMAN
SWITCH
PRESSURE
SWITCH
HIGH
LIMIT
GAS VALVE
TH
TP
PILOT
GENERATOR
PILOT
IGNITER
BK
W
WR
BK - BLACK
R - RED
W - WHITE
H0321000 Rev E
WW
BK
R
TP/TH
W
W
W
R
BK
BK
BK
52°C
(126°F)
42°C
(108°F)
HIGH
LIMIT
BKBK
EARTH
BONDING
LUG
240°C (464°F)
VENT
TEMPERATURE
LIMIT
WW
®