Rheem RTGH-95XLP-2 User manual

95% CONDENSING
TANKLESS
WATER HEATER
AP18161-1 (11/16)
Do not destroy manual. Please read
carefully and keep in a safe place
for future reference.
CERTIFIED
R
WARNING:
This water heater is not suitable
for use in manufactured (mobile)
homes.
WARNING:
If the information in these
instructions is not followed
exactly, a fire or explosion may
result, causing death, personal
injury, or property damage.
For Your Safety!
• Do not store or use gasoline
or other flammable vapors and
liquids in the vicinity of this or
any other appliance. To do so
may result in an explosion or
fire.
• Installation and service must
be performed by a qualified
installer, service agency, or the
gas supplier.
What to Do If
You Smell Gas
• Do not try to light any
appliance.
• Do not touch any electrical
switch; do not use any
phone in your building.
• Immediately call your gas
supplier from a neighbor’s
phone. Follow the gas supplier’s
instructions.
• If you cannot reach your
gas supplier, call the fire
department.
• Do not return to your home until
authorized by the gas supplier
or fire department.
D
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®
USE AND CARE MANUAL
With Installation Instructions
for the Installer
Condensing Direct Vent and Outdoor
199,900 Btu/hr, 180,000 Btu/hr and
157,000 Btu/hr Models

Important Safety Information
Safety Precautions ��������������������������������������������������������������������� 2–8
Product Information
Product Information ������������������������������������������������������������������������ 8
Specifications ��������������������������������������������������������������������������� 9, 10
General Descriptions��������������������������������������������������������������� 11, 12
Using Your Water Heater
Setting the Water Temperature������������������������������������������������� 13, 14
Caring for Your Water Heater
Water Heater Inspections������������������������������������������������������� 15, 16
Care and Cleaning ������������������������������������������������������������������ 17, 18
Preventive Maintenance ��������������������������������������������������������������� 19
Draining the Water Heater��������������������������������������������������������20–22
Freeze Protection ������������������������������������������������������������������������� 22
Vacation and Extended Shutdown ����������������������������������������������� 23
Troubleshooting Chart ������������������������������������������������������������ 23, 24
Service Error Code Chart������������������������������������������������������� 25, 26
If You Need Service
Call for Assistance������������������������������������������������������������������������ 26
Safety
Installation Instructions
Standards Compliance ������������������������������������������������������������������ 28
Choosing a Location�����������������������������������������������������������������28, 29
Product Inspection������������������������������������������������������������������������� 30
Water Heater Installation��������������������������������������������������������� 30–33
Venting������������������������������������������������������������������������������������� 34–46
Water Quality/Supply���������������������������������������������������������������� 47-51
Condensate ����������������������������������������������������������������������������������� 51
Gas Supply�������������������������������������������������������������������������������52-57
Electrical Wiring������������������������������������������������������������������������57-61
Remote Control Installation�������������������������������������������������������60-61
Insulation Blankets ������������������������������������������������������������������������ 62
Installation Checklist���������������������������������������������������������������������� 63
Piping for Space Heaters �������������������������������������������������������������� 64
Recirculation Control ���������������������������������������������������������������� 65-67
Activating the Water Heater������������������������������������������������������ 68-69
Setting the Water Temperature��������������������������������������������������70-72
High-Altitude Dip Switch Adjustments�������������������������������������� 72-73
Water Saving Control Option���������������������������������������������������� 74-75
Maintenance Notice Option������������������������������������������������������ 76-77
Parts Replacement������������������������������������������������������������������� 78-79
Warranty Information�����������������������������������������������������������������83-84
2
CONTENTS
READ THE SAFETY INFORMATION
Your safety and the safety of others are very important.
There are many important safety messages in this manual
and on your appliance. Always read and obey all safety
messages.
This is the safety alert symbol. Recognize this
symbol as an indication of Important Safety
Information! This symbol alerts you to potential
hazards that can kill or hurt you and others.
All safety messages will follow the safety alert symbol
and either the word “DANGER,” “WARNING,” “CAUTION,”
or “NOTICE.”
These words mean:
IMPORTANT SAFETY INFORMATION
WARNINGS:
• This water heater is not approved for use in
manufactured (mobile) homes!
• Improper installation, adjustment, alteration, service,
or maintenance can cause death, personal injury, or
property damage. Follow the instructions in this manual.
READ ALL INSTRUCTIONS
BEFORE USING.
Be sure to read and understand the entire Use and Care Manual
before attempting to install or operate this water heater. It
may save you time and money. Pay particular attention to the
Safety Instructions. Failure to follow these warnings could result
in death or serious bodily injury. Should you have problems
understanding the instructions in this manual, or have any
questions, STOP and get help from a qualified service technician
or the local gas utility.
WARNING:
California Proposition 65
This product contains chemicals known to the state of California
to cause cancer, birth defects, or other reproductive harm.
DANGER: An imminently hazardous situation that
will result in death or serious injury.
NOTICE: Attention is called to observe a specified
procedure or maintain a specific condition.
CAUTION: A potentially hazardous situation that
may result in minor or moderate injury.
WARNING: A potentially hazardous situation
that can result in death or serious injury and/or damage to
property.

Safety
3
IMPORTANT SAFETY INFORMATION
DANGER
FLAMMABLES
Flammable Vapors
Water heater has a main
burner flame.
The main burner flame:
1. which can come on
at any time and
2. will ignite flammable
vapors.
Vapors:
1. cannot be seen,
2. are heavier than air,
3. go a long way on the
floor and
4. can be carried from
other rooms to the
main burner flame by
air currents.
Vapors from flammable
liquids will explode and
catch fire causing death or
severe burns.
Do not use or store flammable
products such as gasoline,
solvents or adhesives in the
same room or area near the
water heater.
Keep flammable products:
1. far away from heater,
2. in approved containers,
3. tightly closed and
4. out of children's reach.
Installation:
Do not install water heater
where flammable products will
be stored or used unless the
main burner flame is at least
18" above the floor. This will
reduce, but not eliminate, the
risk of vapors being ignited
by the main burner flame.
Read and follow water heater warnings and instructions. If
owners manual is missing, contact the retailer or manufacturer.
Water Heater Venting Safety
DANGER:
• Failure to install and properly vent the water heater to
the outdoors as outlined in the “Venting” section of the
Installation Instructions in this manual will result in
death from fire, explosion, or asphyxiation from carbon
monoxide. NEVER operate this water heater unless it is
properly vented and has the air supply piping properly
installed and terminated to the outdoors.
• Be sure to inspect the vent terminal, the air intake,
and the vent system on the water heater for proper
installation at initial start-up and at least annually
thereafter. Refer to the “Care and Cleaning” section
of this manual for more information regarding vent
system inspection.
WARNINGS:
• Gasoline and other flammable liquids, materials,
and vapors (including paint thinners, solvents,
and adhesives) are extremely dangerous. DO NOT
handle, use, or store gasoline or other flammable or
combustible materials anywhere in the vicinity of a
water heater or any other appliance. Be sure to read
and follow the labels on the water heater, as well as the
warnings printed in this manual. Failure to do so can
result in death, bodily injury, or property damage.
• Combustible construction refers to adjacent walls and
ceilings and should not be confused with combustible
or flammable products and materials. Combustible
materials, such as clothing, cleaning materials, or
flammable liquids, should never be stored in the vicinity
of this or any gas appliance. Fire or explosion can occur
causing death, personal injury, and/or property damage.
See page 29 for clearances to combustible materials.
• Follow vent manufacturer’s instructions for venting
installation, including additional clearances from
combustibles, to avoid conditions that can lead to
death, personal injury, and/or property damage.
• Use tankless water heater manufacturer-approved
Schedule 40 PVC (foam core is not permitted at any
time), Schedule 80 PVC, CPVC, ABS, UL 1738-listed
Category III Stainless Steel, or InnoFlue® PP. No other
vent material is permitted. For Canada, installations
must follow ULC S636 for exhaust venting.
• Moisture in the flue gas will condense as it leaves the
vent terminal. In cold weather this condensate can
freeze on the exterior wall, under the eaves, and on
surrounding objects. Some discoloration to the exterior
of the building is to be expected. However, improper
location or installation may result in severe damage to
the structure or exterior finish of the building.
• For multiple-unit installation, a minimum distance
between vent terminations must be maintained to
prevent recirculation of vent gases. See page 39 for
information on venting and clearances to multiple
terminations.
CAUTIONS:
• Ensure that the appliance vent is securely glued and
attached to the vent connection on the top of the water
heater. DO NOT USE SCREWS.
• DO NOT operate without the condensate drain connected
and routed to a proper drain.

4
IMPORTANT SAFETY INFORMATION
Water Supply Safety
DANGER
!
HOT
Water temperature over 125°F (52°C)
can cause severe burns instantly or
death from scalds.
Children,disabled and elderly are
at highest risk of being scalded.
See instruction manual before
setting temperature at water
heater.
Feel water before bathing or
showering.
Temperature limiting valves are
available, see manual.
BURN
Temperature Conversion Chart °F/°C
85 100 102 104 106 108 110 112 114 116 118 120 125 130 140 °F
29 38 39 40 41 42 43 44 46 47 48 49 52 54 60 °C
Time/Temperature Relationship in Scalds
120°F (49°C) More than 5 minutes
125°F (52°C) 1 1/2 to 2 minutes
130°F (54°C) About 30 seconds
135°F (57°C) About 10 seconds
140°F (60°C) Less than 5 seconds
145°F (63°C) Less than 3 seconds
150°F (66°C) About 1 1/2 seconds
155°F (68°C) About 1 second
Table courtesy of Shriners Burn Institute
Water Temperature Time to Produce
a Serious Burn
Safety
!
DANGERS:
• WATER TEMPERATURE SETTINGS
– Safety and energy conservation
are factors to be considered when
selecting the water temperature
setting of a water heater’s remote
control. Water temperatures above
125°F (52°C) can cause death
or severe burns from scalding.
Be sure to read and follow the
warnings outlined on the pictured
label.
• There is a hot water scald potential
if the water temperature is set
too high. Households with small
children, the disabled, or elderly
persons may require a 120°F
(49°C) or lower temperature setting
to prevent contact with “HOT”
water.
• Before manually operating the
relief valve, make certain no one
will be exposed to the danger
of the hot water released by
the valve. The water may be hot
enough to create a scald hazard.
The water should be released into
a suitable drain to prevent injury or
property damage.
• Failure to perform the recommended Routine Preventive
Maintenance can harm the proper operation of this
water heater, which can cause carbon monoxide
dangers, excessive hot water temperatures, and other
potentially hazardous conditions.
!
WARNINGS:
• IMPORTANT: DO NOT apply heat to the HOT or COLD
water connections. If sweat connections are used,
sweat tubing to adapter before fitting adapter to the
water connections on heater. Any heat applied to the
water supply fittings will permanently damage the
internal components of the water heater.
• In case the pipe insulation is not rated for the
appropriate weather conditions, install electric heat
tracing or equivalent to prevent freezing of the pipes.
DO NOT insulate or block the drain valve on the hot
outlet fitting. If the pipes are allowed to freeze, the
water heater and the pipes may malfunction or leak due
to freezing water.
• Failure to drain the water heater as described on page
20 can cause serious personal injuries from scalding
and/or damage the water heater.
CAUTIONS:
•This water heater must only be used
with the following water supply system
conditions:
– With clean, potable water free of corrosive
chemicals, sand, dirt, or other contaminants.
– With inlet water temperatures above 32°F
(0°C), but not exceeding 120°F (49°C).
– DO NOT reverse the hot and cold water
connections. The water heater will not operate.
•Even when drained properly, a small
amount of water will remain in the water
heater. In cold weather conditions, this
water can freeze. If this happens, allow
the defrost protection on the heater
at least 30 minutes to melt the frozen
water or the water heater may not work
properly.
NOTICE:
The factory setting allows operating
temperatures between 100°F (38°C) and 120°F
(49°C). Temperatures of 85°F (29°C) and up to
140°F (60°C) can be achieved with the MAIN
(UMC-117) remote control. Temperatures of
85°F (29°C) can be achieved with the Bath
(USC-117 or USC2-117) remote control. Only
qualified service personnel should perform this
adjustment. Only factory-authorized remote control(s) should be
used.

5
IMPORTANT SAFETY INFORMATION
WARNINGS:
• The installation of gas piping must comply with local
utility company requirements and/or in the absence of
local codes, use the latest edition of National Fuel Gas
Code (NFGC), ANSI Z223.1/NFPA 54, or CAN/CSA B149.1,
Natural Gas and Propane Installation Code.
• If inlet gas pressure is out of allowable range [4.0” w.c.
(1.0kPa) – 10.5” w.c. (2.6kPa)] for Natural Gas, or [8.0”
w.c. (2.0kPa) – 13.0” w.c. (3.2kPa)] for LP gas, a gas
pressure regulator must be installed to maintain the
allowable inlet gas pressure.
• Should overheating occur or the gas supply fail to shut
off, turn off the manual gas control valve to the water
heater.
CAUTIONS:
• DO NOT attempt repair of electrical wiring, gas piping,
remote control, burners, vent connectors, or other safety
devices. Refer repairs to qualified service personnel.
• Turn off the manual gas shut-off valve if the water
heater has been subjected to overheating, fire, flood,
physical damage, or if the gas supply fails to shut off.
• DO NOT turn on the water heater unless the water and
gas supplies are completely opened.
Natural Gas and Liquefied Petroleum Safety
DANGERS:
• Never attempt to convert the water heater from natural
gas to LP or vice versa. The water heater must only use
the fuel type in accordance with listing on data plate—
natural gas for natural gas units and LP for LP units.
Any other fuel usage will result in death or serious
personal injury from fire and/or explosion. This water
heater is not certified for any other fuel type.
• Both natural gas and propane (LP) have an odorant
added to aid in detecting a gas leak. Some people
may not physically be able to smell or recognize this
odorant. If you are unsure or unfamiliar with the
smell of natural gas or LP, ask the gas supplier. Other
conditions, such as “odorant fade,” which causes
the odorant to diminish in intensity, can also hide or
camouflage a gas leak.
• Water heaters using LP gas are different from natural
gas models. A natural gas water heater will not
function safely on LP and vice versa.
• LP must be used with great caution. It is heavier than
air and will collect first in lower areas, making it hard
to detect at nose level.
• Before attempting to light the water heater, make sure
to look and smell for gas leaks. Use a soapy solution
to check all gas fittings and connections. Bubbling at
a connection indicates a leak that must be corrected.
When smelling to detect a gas leak, be sure to also sniff
near the floor.
• Gas detectors are recommended in LP and natural
gas applications and their installation should be
in accordance with the detector manufacturer’s
recommendations and/or local laws, rules, regulations,
or customs.
• Combustible materials, such as clothing, solvents,
cleaning materials, or flammable liquids, must not be
placed in the vicinity of the water heater.
• If a gas leak is present or suspected:
– DO NOT attempt to find the cause yourself.
– Never use an open flame to test for gas leaks. The gas can
ignite resulting in death, personal injury, or property damage.
– Follow the steps listed under “What to Do If You Smell Gas”
found on the front cover of this manual.
Safety

6
IMPORTANT SAFETY INFORMATION
Before operating this water heater, be sure to read and
follow the instructions on the label pictured below and all
other labels on the water heater, as well as the warnings
printed in this manual.
Failure to do so can result in unsafe operation of the water
heater, resulting in death, personal injury, or property
damage. Should you have any problems reading or
following the instructions in this manual, STOP and get
help from a qualified service technician.
WARNING : If you do not follow these instructions exactly, a fire or explosion may result
causing property damage, personal injury or loss of life.
FOR YOUR SAFETY READ BEFORE OPERATING
1.STOP! Read the safety information above on this label.
2.Turn off all electric power to the appliance.
3.Do not attempt to light the burner by hand.
4.Turn the Gas Shutoff Valve located on the outside of the unit
clockwise to the "OFF" position.
5.Wait five (5) minutes to clear out any gas. If you then smell gas, STOP! Follow "B" in
the safety information above on this label. If you don't smell gas, go to the next step.
6.Turn the Gas Shutoff Valve located on the outside of the unit counterclockwise to
the "ON" position.
7.Turn on all electric power to the appliance.
8.If the appliance will not operate, follow the instructions "To Turn Off Gas To Appliance"
and call your service technician or gas supplier.
TO TURN OFF GAS TO APPLIANCE
1 . Turn off all electric power to the appliance if service is to be performed.
2 . Turn the Gas Shutoff Valve located on the outside of the unit clockwise to the "OFF" position.
GAS SHUTOFF
VALVE
OPEN CLOSE
OPERATING INSTRUCTIONS
Safety

7
IMPORTANT SAFETY INFORMATION
Electrical Safety
DANGER:
• Shock Hazard – Make sure the electrical power to the
water heater is off to avoid electric shock that will
result in death or serious personal injury.
WARNINGS:
• For your safety, the information in this manual must
be followed to minimize the risk of fire, explosion, or
electric shock that can result in death, personal injury,
and/or property damage.
• Field wiring connections and electrical grounding must
comply with local codes or, in the absence of local
codes, with the latest edition of the National Electrical
Code, ANSI/NFPA 70, or in Canada, Canadian Electrical
Code, CAN/CSA C22.1, Part 1.
CAUTIONS:
• Label all wires prior to disconnecting for service. Wiring
errors can cause dangerous and improper operation.
Verify correct operation after servicing.
• For your safety, burner inspection and cleaning should
be performed only by qualified service personnel.
• Make certain the power to the water heater is OFF
before removing the unit cover panel. Exposed
electrical components and moving parts can cause
personal injuries.
• For your safety, DO NOT attempt repair of electrical
wiring, gas piping, remote control, burners, vent
connectors, or other safety devices. Refer repairs to
qualified service personnel.
Safety
California law requires that water heaters must be braced,
anchored, or strapped to resist falling or horizontal
displacement due to earthquake motions. For water
heaters up to 52-gallon capacity, a brochure with generic
earthquake bracing instructions can be obtained from:
Office of the State Architect, 1102 Q Street, Suite 5100,
Sacramento, CA 95814, or you may call 916-445-8100 or
ask a water heater dealer.
However, applicable local codes shall govern installation.
For residential water heaters of a capacity greater than
52 gallons or tankless-style, consult the local building
jurisdiction code for acceptable bracing procedures.
FOR INSTALLATIONS IN THE STATE OF CALIFORNIA

8
IMPORTANT SAFETY INFORMATION
General Installation and Maintenance Safety
WARNINGS:
• This water heater must be installed in accordance
with these instructions, local codes, utility company
requirements and/or in the absence of local codes,
use the latest edition of the American National
Standard/National Fuel Gas Code (NFGC), ANSI Z223.1
and National Fire Protection Association, NFPA 54, or
in Canada, CAN/CSA B149.1, Natural Gas and Propane
Installation Code, and the latest edition of the
National Electrical Code, ANSI/NFPA 70, or in Canada,
Canadian Electrical Code, CAN/CSA C22.1, Part 1.
• For your safety, DO NOT attempt to disassemble this
water heater for any reason. Improper adjustments,
alterations, service, or maintenance can cause death,
personal injury, or property damage.
SAVE THESE INSTRUCTIONS
SAFETY PRECAUTIONS:
Read this manual entirely before installing and/or operating
the water heater.
Use this water heater only for its intended purpose as
described in this Use and Care Manual.
Have the installer show you the location of the gas shut-
off valve and how to shut it off if necessary. Turn off
the manual shut-off valve if the water heater has been
subjected to overheating, fire, flood, physical damage, or if
the gas supply fails to shut off.
Be sure your water heater is properly installed in
accordance with local codes and the provided installation
instructions.
DO NOT attempt to repair or replace any part of your water
heater unless it is specifically recommended in this manual.
All other servicing should be referred to a qualified service
technician.
PRODUCT INFORMATION
For Your Records
Write down and save the following product information
along with the original sales slip and/or cancelled check.
The model and serial numbers can be found on the top
label on the right side of the water heater.
MODEL NUMBER:
SERIAL NUMBER:
DATE OF INSTALLATION:
INSTALLING COMPANY/PHONE NUMBER:
PLUMBING CONTRACTOR/PHONE NUMBER:
See page 26 for additional service information.
Read This Manual
Inside you will find many helpful hints on how to use and
maintain your water heater properly. A little preventive care on
your part can save you time and money over the life of your
water heater.
You’ll find many answers to common problems in the
Troubleshooting Chart on pages 23 and 24. Always refer to
this chart before calling for service. Referring to this chart
before calling may answer your question(s) and eliminate the
need for service.
Preoperating Checklist
Is the main gas valve to the water heater turned on?
Is the fuse in place or is the breaker turned on?
Does the water heater’s electronic ignition light?
Is the water temperature set to a safe temperature?
Is the water heater connected to a floor drain?
Is the water heater properly vented to the outside?
Is the water heater installed in a safe location away
from flammable materials and/or freezing conditions?
Product Information Safety

9
PRODUCT INFORMATION
Product Information
303/8"
(772 mm)
275/8"
(702 mm)
33/8"
(86 mm)
51/2"
(140 mm)
61/4"
(159 mm)
177/8"
(454 mm)
185/8"
(473 mm)
93/4"
(248 mm)
21/4"
(59 mm)
51/2"
(140 mm)
61/8"
(156 mm)
21/8"
(54 mm)
37/8"
(98 mm)
27/8"
(73 mm)
41/8"
(105 mm)
91/2"
(241 mm)
11/2"
(38 mm)
Specifications – Direct-Vent Models
17 7/8"
(454 mm)
18 5/8"
(473 mm)
27 5/8"
(702 mm)
93/4"
(248 mm)
21/4"
(59 mm)
51/2"
(140 mm)
61/8"
(156 mm)
21/8"
(54 mm)
37/8"
(98 mm)
27/8"
(73 mm)
41/8"
(105 mm)
91/2"
(241 mm)
11/2"
(38 mm)
Specifications – Outdoor Models

10
PRODUCT INFORMATION
Specifications
Product Information
The following product informa-
tion can be found from the rating
label on this water heater.
A. Model Number
B. Serial Number
C. Data Bar Code
D. Heater Type
E. Installation Type
F. Type of Gas
G. Max. Inlet Gas Pressure
H. Min. Inlet Gas Pressure
J. Recovery Rating
K. Max. BTU Input Rating
L. Min. BTU Input Rating
M. Manifold Gas Pressure
N. Certification Stamp
P. Alternate Approval Stamp
Q. Clearances
English Rating Label
English/French Rating Label