Raypak 503-2003 Manual

INSTALLATI N & PERATING
INSTRUCTI NS
CATALOG NO. 3400.53G Effective: 04-16-10 Replaces: 09-12-08 P/N 241288 Rev. 8
WARNING: mproper installation, adjustment, alteration, service or maintenance can
cause property damage, personal injury, exposure to hazardous materials* or loss of
life. Review the information in this manual carefully. *This unit contains materials that
have been identified as carcinogenic, or possibly carcinogenic, to humans.
F R Y UR SAFETY: Do not store or use gasoline or other flammable vapors and
liquids or other combustible materials in the vicinity of this or any other appliance. To
do so may result in an explosion or fire.
WHAT T D IF Y U SMELL GAS:
• Do not try to light any appliance.
• Do not touch any electrical switch; do not use any phone in your building.
• mmediately call your gas supplier from a neighbor's phone. Follow the gas
supplier's instructions.
• f you cannot reach your gas supplier, call the fire department.
nstallation and service must be performed by a qualified installer, service agency or
the gas supplier.
This manual should be maintained in legible condition and kept adjacent to the heater or in a safe place for future
reference.
Models 503–2003
Types H & WH
L
W

2
Rev. 8 reflects the following:
Changes to: Table on page 9, Figs 11-12 on page 15, Table I and text changers on page 20, Fig. 18 on page 21, Fig. 21
on page 22, Figs. 22-28 on pages 25-30, Table N on page 28, Modes 1,4, 6 and 8 on pages 30-32, Heater Sequence of
Operation section on page 36, U B iagnostic Board section on page 38, wiring diagrams on pages 39 and 40, U B Fault
History section on page 48.
Additions: Fig. 2 on page 6,Low-lead requirement on page 5, Fig. 8 on page 11, Caution on page 20, Fig. 22 on page 22,
Fig. 35 on page 32, note on page 38, Filter Maintenance and Filter Replacement instructions (including Figs. 48 and 49) on
page 50.

WARNINGS 4
BEF RE INSTALLATI N 5
Product Receipt 5
Model Identification 5
Ratings and Certifications 5
Installations at Elevation 5
Component Locations 6
General Information 6
GENERAL SAFETY 7
Time/Temperature Relationships in
Scalds 7
INSTALLATI N 8
Installation Codes 8
Equipment Base 8
Clearances 8
Combustion and Ventilation Air 9
Conventional Combustion Air Supply 11
Water Piping 12
Hydronic Heating 14
Gas Supply 19
Electrical Power Connections 20
Field Wiring Connection 22
Venting 22
Venting Installation Tips 24
Venting Configurations 24
Outdoor Installation 29
Controls 30
Heater Sequence of Operation 36
WIRING DIAGRAMS 39
START-UP 41
Pre Start-up 41
Start-Up 42
PERATI N 45
Lighting Instructions 45
To Turn Off Gas To Appliance 46
TR UBLESH TING 47
U B Fault History 48
MAINTENANCE 48
Suggested Minimum
Maintenance Schedule 48
Preventative Maintenance Schedule 49
Filter Maintenance 50
Filter Replacement 50
APPENDIX 51
Inside Air Contamination 51
IMP RTANT INSTRUCTI NS F R
THE C MM NWEALTH F
MASSACHUSETTS 52
WARRANTY 53
START-UP CHECKLIST 54
C NTENTS
3

4
DANGER: Indicates the presence of immediate hazards which will cause severe
personal injury, death or substantial property damage if ignored.
WARNING: Indicates the presence of hazards or unsafe practices which could cause
severe personal injury, death or substantial property damage if ignored.
CAUTI N: Indicates the presence of hazards or unsafe practices which could cause
minor personal injury or product or property damage if ignored.
N TE: Indicates special instructions on installation, operation, or maintenance which
are important but not related to personal injury hazards.
DANGER: Make sure the gas on which the heater
will operate is the same type as that specified on the
heater rating plate.
WARNING: Should overheating occur or the gas
supply valve fail to shut, do not turn off or disconnect
the electrical supply to the heater. Instead, shut off
the gas supply at a location external to the heater.
WARNING: o not use this heater if any part has
been under water. Immediately call a qualified
service technician to inspect the heater and to
replace any part of the control system and any gas
control which has been under water.
WARNING: To minimize the possibility of improper
operation, serious personal injury, fire, or damage to
the heater:
• Always keep the area around the heater free of
combustible materials, gasoline, and other
flammable liquids and vapors.
• Heater should never be covered or have any
blockage to the flow of fresh air to the heater.
WARNING - CALIF RNIA PR P SITI N
65: This product contains chemicals known to the
State of California to cause cancer, birth defects or
other reproductive harm.
WARNING: Risk of electrical shock. More than one
disconnect switch may be required to de-energize
the equipment before servicing.
CAUTI N: This heater requires forced water
circulation when the burner is operating. See
minimum and maximum flow rates. Severe damage
will occur if the heater is operated without proper
water flow circulation.
CAUTI N: Operation of this heater in low
temperature systems requires special piping.
Harmful internal condensation will occur if the inlet
water temperature does not exceed 120°F. Warranty
claims will be denied when condensation occurs.
CAUTI N: If this heater is to be installed above
radiation level, it must be provided with a low water
cut-off device at the time of heater installation.
CAUTI N: If this heater is to be installed in a
negative or positive pressure equipment room, there
are special installation requirements. Consult factory
for details.
WARNINGS
Pay Attention to These Terms
N TE: Minimum 18 AWG, 105°C, stranded wire
must be used for all low voltage (less than 30 volts)
external connections to the unit. Solid conductors
should not be used because they can cause
excessive tension on contact points. Install conduit
as appropriate. All high voltage wires must be the
same size (105°C, stranded wire) as the ones on the
unit or larger.

5
BEF RE INSTALLATI N
Raypak strongly recommends that this manual be re-
viewed thoroughly before installing your MVB heater.
Please review the General Safety information before
installing the heater. Factory warranty does not apply
to heaters that have been improperly installed or oper-
ated. (Refer to the warranty at the back of this
manual.) Installation and service must be performed
by a qualified installer, service agency or gas supplier.
If, after reviewing this manual, you still have questions
which this manual does not answer, please contact
your local Raypak representative or visit our website at
www.raypak.com.
Thank you for purchasing a Raypak product. We hope
you will be satisfied with the high quality and durability
of our equipment.
Product Receipt
On receipt of your heater it is suggested that you visu-
ally check for external damage to the shipping crate. If
the crate is damaged, make a note to that effect on the
Bill of Lading when signing for the shipment. Next,
remove the heater from the shipping packaging.
Report any damage to the carrier immediately.
On occasion, items are shipped loose. Be sure that
you receive the correct number of packages as indi-
cated on the Bill of Lading.
Claims for shortages and damages must be filed with
the carrier by consignee. Permission to return goods
must be received from the factory prior to shipping.
Goods returned to the factory without an authorized
Returned Goods Receipt number will not be accepted.
All returned goods are subject to a restocking charge.
When ordering parts, you must specify the model and
serial number of the heater. When ordering under war-
ranty conditions, you must also specify the date of
installation.
Purchased parts are subject to replacement only
under the manufacturer’s warranty. ebits for defec-
tive replacement parts will not be accepted. Parts will
be replaced in kind only per Raypak’s standard war-
ranties.
Model Identification
The model identification number and heater serial
number are found on the heater rating plate located on
the upper rear jacket panel of the heater. The model
number will have the form H7-2003 or similar depend-
ing on the heater size and configuration. The letter(s)
in the first group of characters identifies the application
(H = Hydronic Heating, WH = omestic Hot Water
( HW)). The number which follows identifies the firing
mode (7 = electronic modulation). The second group
of characters identifies the size of the heater (three or
four numbers representing the approximate MBTUH
input), and, where applicable, a letter, indicating the
manufacturing series.
Ratings and Certifications
Standards:
• ANSI Z21.13 · CSA 4.9 - latest edition, Gas-Fired
Hot Water Boilers
• CAN 3.1 - latest edition, Industrial and
Commercial Gas-Fired Package Boilers
• ANSI Z21.10.3 · CSA 4.3 - latest edition, Gas Wa-
ter Heaters
• SCAQM Rule 1146.2
• Low-lead content (<.25%) CSA-verified
All Raypak heaters are National Board Approved, and
design-certified and tested by the Canadian Standards
Association (CSA) for the U.S. and Canada. Each
heater is constructed in accordance with Section IV of
the American Society of Mechanical Engineers
(ASME) Heater Pressure Vessel Code and bears the
ASME stamp. This heater also complies with the latest
edition of the ASHRAE 90.1 Standard.
Installations at Elevation
Rated inputs are suitable for up to 4,500 ft elevation
without de-rating. Consult your local representative or
the factory for installations at altitudes over 4,500 ft
above sea level. No hardware changes are required to
the heaters for installations up to 10,000 ft (adjust-
ments may be required).
WARNING: Altering any Raypak pressure vessel
by installing replacement heat exchangers, tube
bundle headers, or any ASME parts not
manufactured and/or approved by Raypak will
instantly void the ASME and CSA ratings of the
vessel and any Raypak warranty on the vessel.
Altering the ASME or CSA ratings of the vessel also
violates national, state, and local approval codes.

General Information
Table A: Basic Data
6
HIGH VOLTAGE
ELECTRICAL CONNECTIONS
Component Locations
Panels omitted for clarity
Fig. 1: Component Locations – Side
Top panel, blower and gas train omitted for clarity
Fig. 4: Component Locations – Top
Fig. 3: Component Locations – Rear
MBTUH
Input
Gas
Conn.
(NPT)
Vent Size
(in.)
Model
No.
Max. Min.
Water
Conn.
(NPT) N P Flue Intake
503 500 125 2 1 1 6 6
753 750 188 2 1 1 6 6
1003 999 250 2-1/2 1-1/4 1 6 6
1253 1250 312 2-1/2 1-1/4 1 8 8
1503 1500 375 2-1/2 1-1/4 1 8 8
1753 1750 438 2-1/2 2 1 8 8
2003 1999 500 2-1/2 2 1 8 8
Panels omitted for clarity
Fig. 2: Component Locations – Front

7
GENERAL SAFETY
To meet commercial hot water use needs, the high
limit safety control on this water heater will shut off the
main gas valve before the outlet temperature reaches
210°F. However, water temperatures over 125°F can
cause instant severe burns or death from scalds.
When supplying general purpose hot water, the rec-
ommended initial setting for the temperature control is
125°F.
This section applies to Hot Water Supply Boilers and
Hot Water Heaters ONLY. For sanitary rinse applica-
tions where outlet temperatures of 180°F to 195°F are
required, a boiler is recommended since the 210°F
limit on water heaters will NOT allow the heater to
maintain these desired sanitary rinse temperatures.
Safety and energy conservation are factors to be con-
sidered when setting the water temperature on the
thermostat. The most energy-efficient operation will
result when the temperature setting is the lowest that
satisfies the needs of the application.
Water temperature over 125°F can cause instant
severe burns or death from scalds. Children, disabled
and elderly are at highest risk of being scalded.
• Feel water before bathing or showering.
• Temperature limiting valves are available.
Maximum water temperatures occur just after the
heater’s burner has shut off. To determine the water
temperature being delivered, turn on a hot water
faucet and place a thermometer in the hot water
stream and read the thermometer.
N TE: When this water heater is supplying general
purpose hot water for use by individuals, a
thermostatically controlled mixing valve for reducing
point of use water temperature is recommended to
reduce the risk of scald injury. Contact a licensed
plumber or the local plumbing authority for further
information.
Water temperature over 125°F can
cause instant severe burns or death
from scalds.
Children, disabled, and elderly are
at highest risk of beingscalded.
See instruction manual before set-
ting temperature at water heater.
Feel water before bathing or show-
ering.
Temperature limiting valves are
available, see manual.
Time/Temperature
Relationships in Scalds
The following chart details the relationship of water
temperature and time with regard to scald injury and
may be used as a guide in determining the safest
water temperature for your applications.
Water
Temp.
Time to Produce Serious
Burn
120°F More than 5 minutes
125°F 1-1/2 to 2 minutes
130°F About 30 seconds
135°F About 10 seconds
140°F Less than 5 seconds
145°F Less than 3 seconds
150°F About 1-1/2 seconds
155°F About 1 second
Table courtesy of The Shriners Burn Institute
Table B: Time to Produce Serious Burn

Equipment Base
The heater should be mounted on a level, structurally
sound surface. The heater is approved for installation
on a combustible surface but must NEVER be
installed on carpeting. Gas-fueled equipment installed
in enclosed parking garages must be located at least
18 in. above the floor.
In addition, the heater shall be installed such that the
gas ignition system components are protected from
water (dripping, spraying, rain, etc.) during appliance
operation or service (circulator replacement, control
replacement, etc.).
If the heater needs to be secured to the ground, use
the brackets that were used to bolt the heater to the
shipping pallet.
Clearances
Indoor Installations
When installed according to the listed minimum clear-
ances from combustible construction, these heaters
can still be serviced without removing permanent
structural construction around the heater. However, for
ease of servicing, a clearance of at least 24 in. in front,
at least 24 in. on the rear and 10 in. above the top of
the heater is required. This will allow the heater to be
8
Heater
Side
Minimum Clearance
from Combustible
Surfaces
Minimum
Service
Clearance
Floor* 0” 0”
Rear 12” 24”
Right Side 1” 1”
Left Side 1” 1”
Top 0” 10”
Front Open 24”
Vent 1” 1”
Table C: Clearances – ndoor nstallations
INSTALLATI N
INSTALLATI N
Installation Codes
Installations must follow these codes:
• Local, state, provincial, and national codes, laws,
regulations and ordinances
• National Fuel Gas Code, ANSI Z223.1/NFPA 54 –
latest edition (NFGC)
• National Electrical Code, ANSI/NFPA 70 - latest
edition (NEC)
• Standard for Controls and Safety evices for
Automatically Fired Boilers, ANSI/ASME CS -1,
(CS -1) when required
• For Canada only: CAN/CSA B149 Natural Gas
and Propane Installation Code and CSA C22.1
C.E.C. Part 1 (C22.1)
The temperature of the water in the heater can be reg-
ulated by using the Raypak Modulating Temperature
Control. To comply with safety regulations, the control
is set at 120°F when shipped from the factory (Mode 3
default setting for Tank Target).
To adjust the water temperature, follow the instruction
for the operation of the control starting on page 30 of
this manual. The control is shown below for identifica-
tion purposes only. (See Fig. 5.)
CAUTI N: Hotter water increases the risk of
scalding! There is a hot water scald potential if the
thermostat is set too high.
Fig. 5: Modulating Temperature Control
* O NOT install on carpeting.
CAUTI N: This heater should be located in an
area where water leakage will not result in damage
to the area adjacent to the appliances or to the
structure. When such locations cannot be avoided, it
is recommended that a suitable catch pan,
adequately drained, be installed under the
appliance. The pan must not restrict air flow.

9
Fig. 6: Minimum Clearances from Combustible
Surfaces – ndoor and Outdoor nstallations
lation codes and the requirements of the gas supplier.
Three sides must be open in the area under the over-
hang. Roof water drainage must be diverted away
from heaters installed under overhangs.
The combustion air intake terminal MUST be used for
outdoor installations. The elbow is shipped loose to be
installed on the rear of the heater at the job site.
Table D: Clearances – Outdoor nstallations
Venting not shown for clarity. Heater must be vented
per instructions in this manual
serviced in its installed location without movement or
removal of the heater.
Service clearances less than the minimum may
require removal of the heater to service either the heat
exchanger or the burner components. In either case,
the heater must be installed in a manner that will
enable the heater to be serviced without removing any
structure around the heater.
utdoor Installations
These heaters are design-certified for outdoor installa-
tion. Heaters must not be installed under an overhang
unless clearances are in accordance with local instal-
Combustion and Ventilation Air
Indoor Units
This heater must be supplied with sufficient quantities
of non-contaminated air to support proper combustion
and equipment ventilation. Combustion air can be sup-
plied via conventional means where combustion air is
drawn from the area immediately surrounding the
heater, or via direct vent, where combustion air is
drawn directly from outside. All installations must com-
ply with the requirements of the NFGC (U.S.) and
B149 (Canada), and all local codes.
N TE: Use of this heater in construction areas
where fine particulate matter, such as concrete or
dry-wall dust, is present may result in damage to the
heater that is not covered by the warranty. If
operated in a construction environment, a clean
source of combustion air must be provided directly to
the heater.
CAUTI N: Combustion air must not be
contaminated by corrosive chemical fumes which
can damage the heater and void the warranty. (See
the Appendix.)
N TE: It is recommended that the intake vent be
insulated to minimize sweating.
Heater
Side
Min. Clearance
from Combustible
Surfaces
Minimum
Service
Clearance
Rear 12” 24”
Front Open 24”
Right Side 1” 1”
Left Side 1” 1”
Top Unobstructed 10”
Vent
Termination 12” 12”

10
U.S. Installations1Canadian Installations2
AClearance above grade, veranda, porch,
deck, or balcony 1ft (30 cm) 1 ft (30 cm)
BClearance to window or door that may be
opened
4ft (1.2m) below or to side
of opening; 1 foot (30 cm)
above opening
3ft (91 cm)
C Clearance to permanently closed window **
D
Vertical clearance to ventilated soffit located
above the terminal within a horizontal dis-
tance of 2 ft (61cm) from the centerline of the
terminal
5ft (1.5m) *
EClearance to unventilated soffit **
FClearance to outside corner **
GClearance to inside corner 6ft (1.83m) *
HClearance to each side of center line ex-
tended above meter/regulator assembly *
3ft (91 cm) within a height
15ft above the me-
ter/regulator assembly
IClearance to service regulator vent outlet *6ft (1.83m)
J
Clearance to non-mechanical air supply inlet
to building or the combustion air inlet to any
other appliance
4ft (1.2m) below or to side
of opening; 1 ft (30 cm)
above opening
3ft (91 cm)
KClearance to mechanical air supply inlet 3ft (91 cm) above if within
10 ft (3m) horizontally 6ft (1.83m)
LClearance above paved sidewalk or paved
driveway located on public property 7ft (2.13m) 7ft (2.13m) t
MClearance under veranda, porch, deck or
balcony *12 in. (30 cm) TT
1Inaccordance with the current ANSIZ223.1/NFPA54National Fuel Gas Code
2Inaccordance with the current CAN/CGA-B149 Installation Codes
tVent terminal shall not terminate directly above sidewalk or paved driveway located between 2 single family dwellings that serves
both dwellings
TT Permitted only if veranda, porch, deck, or balcony is fully open on a minimumof two sides beneath the floor and top of terminal and
underside of veranda, porch, deck or balcony is greater than 1 ft(30cm)
*Clearances in accordance with local installation codes and the requirements of the gas supplier
Fig. 7: Minimum Clearances from Vent/Air nlet Terminations – ndoor and Outdoor nstallations
Table E: Vent/Air nlet Termination Clearances