TriangleTube Marquis TWH180 User manual

Read the Installation Manual carefully and be sure that your water heater has been properly
assembled, installed and maintained. Failure to follow these instructions exactly could result in a
re or explosion, serious bodily injury and/or property damage.
Installation and service must be performed by a qualied plumber, a licensed gas tter, or a pro-
fessional technician in accordance with all local codes.
Improper installation and/or operation by an unqualied person will void the warranty.
– Do not store or use gasoline or other ammable vapors and liquids in the vicinity of this or any
other appliance.
– 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 re department.
– Installation and service must be performed by a qualied installer, service agency or the gas
supplier.
If the information in these instructions is not followed exactly, a re or explosion may result,
causing property damage, personal injury, or death.
Marquis
User’s Manual
TWH180 / TWH180LP
Gas Condensing Water Heater
• Natural Gas(NG) – TWH180
• Liquid Propane Gas (LP) – TWH180LP
Model
WARNING
Date: 7/10/15 2015-7 Marquis User

i
Product and Safety Information
Marquis Operation ........................................................................................................ 1
Denitions ..................................................................................................................... 1
Operating Instructions ............................................................................................... 2-4
Method of Operation
Before Operation .......................................................................................................... 5
Operation ...................................................................................................................... 5
Display Panel ............................................................................................................... 6
LCD Display .................................................................................................................. 7
Operating Mode ............................................................................................................ 8
DHW Setpoint Change Modes ..................................................................................... 9
Error Mode .................................................................................................................. 10
Information Mode ........................................................................................................ 11
Installer Mode ............................................................................................................. 12
Maintenance
Regular Maintenance ................................................................................................. 13
Maintenance Procedures ....................................................................................... 13-15
Troubleshooting
Troubleshooting .......................................................................................................... 16
Diagnostics ............................................................................................................ 17-18
Error Codes
Error Codes ...........................................................................................................19-21
Control Logic ......................................................................................................... 22-24
Table of Contents

1
Marquis Operation
Cold water is heated by the burner as it passes
through the stainless steel heat exchanger. The burn-
er ring rate constantly adjusts to maintain the DHW
setpoint temperature.
To avoid product damage, personal injury, or
even possible death, carefully read, under-
stand, and follow all the instructions in the
Marquis Installation manual before installa-
tion, operation, or service.
ACV-Triangle Tube cannot anticipate every cir-
cumstance that might involve a potential haz-
ard. Therefore, all possible incidents are not
included in our warnings. Proper installation,
operation, and service are your responsibility.
You must be satised that the operation and
settings of the Water Heater are safe for you
and for others.
Denitions
Safety Symbols are provided in the manual. When a
user fails to adhere to the following requirements, it
may cause death, serious damage, or great property
loss.
Indicates an imminently hazardous situation
which, if not avoided, will result in death or
serious injury.
Indicates a potentially hazardous situation
which, if not avoided, could result in death
or serious injury.
Indicates a potentially hazardous situation
which, if not avoided, may result in minor
or moderate injury. It is also used to alert
against unsafe practices and hazards involv-
ing only property damage.
WARNING
DANGER
WARNING
CAUTION
Product & Safety Information

2
OPERATING INSTRUCTIONS
TO TURN OFF GAS TO APPLIANCE
1. STOP! Read the safety information above on
this label.
2. Set the thermostat to lowest setting.
(Do not use Water Heater unless it is completely
lled with water.)
3. Turn OFF electrical power supply to the Water
Heater.
4. This Water Heater is equipped with an ignition
device which automatically lights the main burn-
er. Do not try to light the burner by hand.
5. Turn gas shut-off valve clockwise to ˝OFF˝ posi-
tion. Do not force
6. Wait ve (5) minutes to clear out any gas. If you
then smell gas, STOP! Follow step ˝B˝ above on
this label. If you don’t smell gas, go to next step.
7. Turn manual gas shut-off valve to ˝ON˝ position.
8. Turn ON electrical power to the appliance.
9. Wait until default temperature (120°F) is dis-
played. Set desired water temperature. Turn hot
water faucet on.
10. Set thermostat to desired setting.
11. If the appliance will not operate, follow the in-
structions ˝To Turn Off Gas To Appliance˝ and call
your service technician or gas supplier.
1. Set the thermostat to lowest setting.
2. Turn off all electric power to the appliance if
service is to be performed.
3. Turn manual gas shutoff valve to ˝OFF˝
position
This appliance must be installed in accordance with
local codes if any; if not, follow ANSI Z223.1/NFPA
54 or CAN/CSA B149.1, Natural Gas and Propane
Installation Code, as applicable.
NOTE : AUTOMATIC GAS SHUT OFF
VALVE IS RESET BY TURNING WATER
FLOW ˝OFF˝ THEN ˝ON˝ AGAIN.
FOR YOUR SAFETY READ
BEFORE OPERATING
If you do not follow these instructions exactly,
a re or explosion could result causing prop-
erty damage, personal injury or loss of life.
A. This appliance does not have a pilot. It is
equipped with an ignition device which au-
tomatically lights the burner. Do not try to
light the burner by hand.
B. BEFORE OPERATING smell all around the
appliance area for gas. Be sure to smell next
to the oor because some gas is heavier
than air and will settle on the oor.
WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electric 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 re department.
C. Use only your hand to push in or turn the gas
control knob. Never use tools. If the knob
will not push in or turn by hand, don’t try to
repair it, call a qualied service technician.
Force or attempted repair may result in a re
or explosion.
D. Do not use this appliance if any part has
been under water. Immediately call a quali-
ed service technician to inspect the appli-
ance and to replace any part of the control
system and any gas control which has been
under water.
WARNING
WARNING
Product & Safety Information

3
Vapors from ammable liquids can explode
and catch re causing death or severe burns.
Do not use or store ammable products such
as gasoline, solvents or adhesives in the same
room or area near the appliance.
Keep ammable products
Far away from Water Heater
In approved containers
Tightly closed
Out of children’s reach
Vapors
Cannot be seen
Are heavier than air
Spread on the oor
Can spread from other rooms to the main
burner by air currents
Do not install the appliance where ammable
products will be stored.
Read and follow Water Heater warnings and
instructions. If owner’s manual is missing con-
tact the retailer or manufacturer.
Use this Water Heater at your own risk.
The outlet temperature of the Marquis Water
Heater is factory preset to 120°F (49°C). The
temperature can only be changed by using the
control panel.
Hot water temperature over 125°F (52°C) can
cause severe burns instantly or death from
scalding. Children, disabled, and elderly are at
the highest risk of being scalded. Do not leave
children or the inrm unsupervised. Check
temperature of hot water before taking a show-
er or bath. To control water temperature to a
particular faucet, temperature limiting valves
can be installed by your service professional.
DANGER
DANGER
Product & Safety Information

4
The Marquis Water Heater must be installed
by a qualied plumber, a licensed gas tter,
or a professional service technician.
Improper installation or operation can cause
serious injury or death.
It also voids the warranty.
• The National Fuel Gas Code NFPA 54 / ANSI
Z223.1
• National Electric Code ANSI/NEPA 70
• All applicable local, state, national and pro-
vincial codes, regulations, and laws.
Proper care is your responsibility. Carefully
read and understand the Operating Informa-
tion in this manual before operating the Mar-
quis Water Heater.
Be aware of the location of the gas shut-off
valve and operation method.
Close the gas shut-off valve immediately if the
appliance is subjected to re, overheating,
ood, physical damage, or any other damag-
ing condition that might affect the operation
of the unit.
The Water Heater must be checked by a quali-
ed technician before resuming operation.
DO NOT use this Water Heater if any part has
been submerged under water. Call a qualied
technician immediately for inspecting the Wa-
ter Heater and for replacing any part of the
control system and any gas control which
has been under water.
Do not power up the unit unless the gas and
water supply valves are fully opened. Make
sure that fresh air intake port and exhaust gas
port are opened and functional.
DO NOT attempt to install, repair, or service
the Water Heater by yourself.
Contact a qualied technician if the Water
Heater needs repair or maintenance.
DO NOT use spray paint, hair spray, or any
other ammable spray near the Water Heater
or the exterior fresh air inlet port. DO NOT
place any items in or around the exterior ex-
haust gas outlet port and/or fresh air inlet
port. It could restrict or block the ow in or
out of the vent system.
After installing the water heater, safety device
must be tested.
While repairing controls, all wires are labeled.
Also, they must be connected in accordance
with the instructions.
Wiring errors can cause improper and dan
gerous operation.
Verify proper operation after servicing.
The gas ignition system components must
be protected from water (dripping, spraying,
rain, etc.) during appliance operation and
service (circulator replacement, condensate
trap, control replacement, etc.).
WARNING
CAUTION
Product & Safety Information

5
Before Operation
1. Check the Gas Type (NG/LP)
When using the unit for the rst time, check if gas
type matches with the gas type of the Water Heater.
(Check whether the gas type which is supplied is NG
or LP and also check the Water Heater gas type.)
The gas type is indicated on the rating plate on side
of the Water Heater.
2. Check the Power (120V 60Hz)
Check whether the appliance is connected properly.
3. Check the Cold Water Inlet valve
Open the appliance water inlet valve. The appliance
will not ignite when insufcient water or no water is
present at the cold water inlet.
4. Check the Gas valve
Check if the manual gas shut-off valve to the appli-
ance is opened.
5. Check the Area Around the Appliance
Remove any combustible or ammable materials and
do not place any wet laundry on the exhaust vent.
Operation
1. Check for Gas leak
Check for gas leak at the gas connection with soapy
water.
2. Check Ventilation
Make sure that there is sufcient inow and outow of
ventilation air while using the unit.
If the ventilation is improper, then the combustion
condition deteriorates inside the appliance and it may
cause shortened life of the appliance.
3. Burn Warning
Be careful not to burn yourself by the ue or pipes.
They are getting extremely hot during operation.
4. Combustibles Warning
Do not use the appliance for any other purpose than
for heating hot water.
Do not store combustibles or ammable material
such as gasoline near the appliance.
Method of Operation

6
Display panel
Buttons Functionality
Push (under 5 seconds) Hold (more than 5 seconds)
A ON/OFF N/A
B N/A Information mode with power ON.
Installer mode with power OFF.
C Adjust set point (95°-125°) Adjust set point (125°-140°)
D N/A Change temperature unit (°C / °F)
E Menu Scroll & Setting Adjustments N/A
Method of Operation

7
LCD Display
LCD has a backlight that will illuminate:
• When a user action has been detected (a button is pressed)
• The timeout is approximately 20 seconds.
S3 S36
S37
S24
S35
S38
S29 S30 S32 S33
S31
1 2 3 4
S15~19S8~14
Segment Name Description
S3 Anti-freeze mode Anti-Freeze mode indicated
S8,S11,S14 Lock mode Lock mode indication
S15 ~ S19 Communication state Communication state indication
S24 DHW mode Water heater operating indication
S29 ~ S33 Dot, colon Separate indication
S35 Celsius mode Celsius temperature reading
S36 Installer mode Unused
S37 Flame signal Flame Signal indication
S38 Fahrenheit mode Fahrenheit temperature reading
1A ~ 4G 8 segment Number and character indication
Method of Operation

8
Operating Mode
After power on, the display shows a sequence of information during start-up. The following indications will
appear:
After start-up, the standby mode will be displayed as shown below.
Indicate on digits Show Time Examples
LCD test: All segments ON
1 seconds
LCD test: All segments OFF
0.5 seconds
Text “Pdn”
1 seconds
Show product number of control family
1 seconds Number “16”
Text “SFn”
1 seconds
Show software version of control family
1 seconds Number “1.01”
Text “Hdn”
1 seconds
Show Hardware version of control family
1 seconds Number “0001”
Indicate Indicator
Current DHW temperature setpoint 1 ~ 4
If the ow is present S24
If ame detected S37
If lock mode is activated S8, S11, S14
Temperature sign Celsius or Fahrenheit S35 or S38
Communication state indicate S15 ~ S19
Method of Operation

9
DHW Setpoint Change Mode
The display shows the following information during water heating temperature setpoint changes.
* Initial DHW setpoint is 120°F (49°C)
* 1st DHW set-point range is 95 ~125°F (35 ~ 52°C)
When button C is pressed shortly at standby mode (not blinking), current DHW setpoint will be displayed
and DHW icon will be blinking.
* 2nd DHW set-point range is 125 ~140°F (52 ~ 60°C).
When button C is pressed continuously at standby mode (not blinking), current DHW setpoint will be dis-
played and DHW icon will be blinking. Also, caution mark(H.) will be presented.
Current DHW setpoint can be changed by rotating dial.
After changing temperature, user should press E button (enter) in order to save the value.
- Changing temperature unit
When button D is pressed continuously (more than 5 seconds), the temperature units will toggle. s
Indicate Indicator
Current setpoint temperature 2, 3, 4
Temperature sign Celsius or Fahrenheit S35 or S38
If display is connected to main controller, normally the communication state will be
indicated. S15 ~ S19
When DHW setpoint range is high : from 125°F (52°C) to 140°F (60°C) 1(H), S29
DHW display blinks. S24
Method of Operation

10
Error mode
The display will show the following information when an Error occurs.
Indicate Indicator
Error ‘ Er : ’ sign Segment 1 is blinking at 1Hz 1, 2 ,S30
Error Code 3, 4
If display is connected to main controller, normally the
communication state will be indicated. S15 ~ S19
Method of Operation

11
Information mode
When button ‘B’ is pressed shortly in standby mode, information display mode will be activated.
Scroll through items by turning the dial E . Press the dial to view the currently selected item.
Index Parameter Description
A: Li or A: GA DHW Flow Current ow value(Li: L/m, GA: GPM)
b: Fr Fan rpm Current fan rpm value
C: Lc Lock Mode Lock mode is (On) or (oFF)
d: OP OP Temperature Current Operating Temperature
E: dH DHW temperature Current DHW temperature
F: Eh Exhaust Temperature Current Exhaust temperature
h: In Inlet Temperature Current Inlet Temperature
L:rt Running Time Display Running Time
L:rt
1: PH Power Supply Time Power Supply Time: 100 hour increments
2: rh Burner Operating Time Burner Operating Time: 1 hour increments
3: rH Burner Operating Time Burner Operating Time: 1,000 hour increments
4: It Ignition Attempts Number Ignition Attempts Number: 10 times unit displayed
5: IH Ignition Attempts Number Ignition Attempts Number: 10,000 times unit
displayed
J: AG AGM Position AGM calibration
Method of Operation

12
Method of Operation
Installer Mode
When button ‘B’ is pressed for 5 seconds with the unit turned off via button ‘A’, installer mode will be
activated.
Scroll through items by turning the dial E .
Select an item to change by pressing button E . Then, the user can change the value by rotating dial E .
After changing, press button E to save the setting.
When button B is pressed again, installer mode will be changed back to power off mode.
Index Numbers Parameter Description
1: EH Error History Previous fault codes (H0~H9)
2: cE Clear Error History Clears error history
3: In System initialize System reset
4: Fu Flow units L/m or GPM
5: FH N/A DO NOT ADJUST
6: FL N/A DO NOT ADJUST
7: dr Reset Running time Reset running time YES/No
8: dl Reset igniting times Reset igniting times YES/No
9: HA High Altitude High Altitude Setting (0: Nomal <1< 2<4 :High Altitude)
10: Cn N/A N/A
11: CI N/A N/A
12: Eh N/A N/A

13
Maintenance
Regular Maintenance
- This manual should remain with the Water Heater.
After Water Heater installation is completed, the
installation manual should be placed in a location
near the Water Heater. Maintenance instructions
should be carried out following the guidelines:
Maintenance procedures [ Daily ]
- Check power source.
Make sure that the power cord is correctly connect-
ed. The power line is connected to the manual switch
inside the Water Heater.
- Check status of the control panel.
Check for any debris on the buttons or display.
Maintenance procedures [Monthly]
- Check vent pipe.
Visually inspect the ue gas vent piping for any signs
of blockage, leakage or deterioration of the piping.
Contact a qualied service technician immediately if
you nd any problem.
- Check air inlet pipe.
Visually inspect the air inlet for obstructions. Inspect
entire length of air piping to ensure the piping is intact
and all joints are properly sealed. Call your qualied
service technician if you notice any problems.
- Check relief valve.
Inspect the Water Heater relief valve and the relief
valve discharge pipe for any signs of weeping or
leakage. If the relief valve often weeps, immediately
contact your qualied service technician for inspect-
ing the Water Heater system.
- Check the condensate outlet.
While the Water Heater is running, check the dis-
charge end of the condensate drain tubing.
Make sure that no ue gas is escaping from the con-
densate drain tubing.
If ue gas is continuously escaping, it is a serious
problem. Call your qualied service technician for in-
specting the Water Heater and condensate line.
- Check vent terminal screen.
Inspect vent terminal screen for debris.
Remove any debris found.
Maintenance procedures [ Daily ]
- Check installation location
To prevent potential severe personal injury, death or
substantial property damage, remove all contami-
nated materials.
If contaminants are found :
Remove products immediately from the area.
In order to check the status of Water Heater, call
a qualied service technician to inspect the Water
Heater for possible damage from corrosion.
DO NOT store combustible materials, gasoline or
any other ammable vapors or liquids near the Wa-
ter Heater. Remove them immediately or store them
other places.
- Check if WATER HEATER casing is closed.
Check if there is any problem with the Water Heat-
er casing and the two upper and lower screws are
tightened well. Water Heater casing must be closed
while it is running.
Daily
Check installation location.
Check if water heater casing is
closed.
Check power source.
Monthly
Check vent pipe.
Check air inlet pipe.
Check relief valve.
Check condensate outlet.
Every 6 Months
Check water heater piping (gas
and water)
Operate relief valve
No plan for long-term
use.
Do not shut Water Heater
down.

14
Maintenance
5. Remove the lter from the plastic assembly and clean it with a toothbrush and clean running water.
6. Dry the lter completely and then reinsert the lter into the plastic assembly.
7. Replace the front cover and then reconnect the power supply to the water heater.
8. Press Power button on the front panel to turn on water heater.
- Cleaning cold water Inlet Filter
1. Place a bucket under the appliance to collect the residual water inside the water heater.
2. Press Power button on the front control panel to turn off the electrical power to the water heater and then
turn off the gas valve.
3. Close water supply valve on the inlet to the appliance. If there is no valve, turn off main water valve.
4. Open the hot water faucets completely.
5. Remove the cold water inlet lter. And then clean it with a toothbrush and clean running water.
6. To rell the water heater, follow the steps of “Cleaning cold water Inlet Filter” in reverse.
- Cleaning Air Intake Filter
- To properly maintain the water heater, you should clean air intake lter every month. A dirty air intake lter
could cause unreliable operation.
To clean air intake lter:
1. Press Power button on the control panel to turn off the water heater.
2. Disconnect power supply to water heater.
3. Remove front cover of water heater.
4. Pull the lter out of air intake adapter.

15
- Flushing the Water Heater
Flushing the Heat Exchanger of the water heater is
required for optimal performance. Refer to the fol-
lowing instructions carefully before attempting the
procedure. If you do not understand the procedure,
contact an authorized technician or licensed profes-
sional. Keep in mind that improper maintenance can
void your warranty.
1. Disconnect electric power to the water heater.
2. Close the shutoff valves on both hot water outlet
and cold water inlet lines. (V1 & V2)
3. Connect one hose “D1” to the valve “V3” and
place the free end in the bucket. Connect another
hoses“D3” to the circulation pump outlet and the
cold water inlet line at the valve “V4”. Connect
other hose “D2” to the circulation pump inlet and
place the free end in the bucket.
4. Pour the instantaneous water heater cleaning
solution into the bucket. Place the hose (D1) and
hose (D2) to the pump inlet into the cleaning
solution.
5. Open service valves (V3 & V4) on the hot water
outlet and cold water inlet lines.
6. Turn on the circulation pump (Operate the pump
and allow the cleaning solution to circulate through
the water heater for at least 1 hour at a rate of 4
gallons per minute.)
7. Rinse the cleaning solution from the water heater
as follows:
- Remove the free end of the drain hose (D1) from
the bucket.
Maintenance
- Close service valve, (V4), and open shutoff valve,
(V2). Do not open shutoff valve, (V1).
- Allow water to ow through the water heater for 5
minutes.
- Close shutoff valve (V2).
8. Disconnect all hoses.
9. Remove the cold water inlet lter from the water
heater and clean out any residues.
10. Reinsert the lter and ensure the lter cap is se-
curely tightened.
11. Connect electrical power to the water heater.
Maintenance procedures [Every 6 Months]
- Check piping. (gas and water)
Visually inspect for leaks around internal water pip-
ing. Also inspect external water piping, circulators,
relief valve and ttings. Immediately call a qualied
service technician to repair any leaks.
Leaks must be xed by a qualied service technician
immediately. Failure to comply with this instruction
could result in severe personal injury, death or sub-
stantial property damage.
- Operate relief valve
Before following the procedure, verify that relief valve
outlet has been piped to a safe place of discharge,
avoiding any possibility of scalding from hot water.
If water ows freely, release the lever and allow the
valve to seat. Watch the end of the relief valve dis-
charge pipe to ensure that the valve does not weep
after the line has had time to drain. If the valve weeps,
lift the seat again to attempt to clean the valve seat.
If the valve continues to weep, contact your quali-
ed service technician for inspecting the valve and
system. If water does not ow from the valve even
though you have lifted the lever completely, the valve
or discharge line may be blocked. Shut down the
Water Heater immediately. Call your qualied service
technician to inspect the water heater and system.
D1
D2 D3
Leaks must be xed by a qualied service
technician immediately. Failure to comply with
this instruction could result in severe personal
injury, death or substantial property damage.
This discharge line must be installed by a
qualied heating installer or a service
technician.
WARNING
V3
V1
V4
V2

16
Troubleshooting
Troubleshooting
Symptom Possible Causes
Burner does not ignite even if hot
water is opened.
Make sure that the ON/OFF button on the Control Panel has been turned ON.
If the monitor on the Control Panel is blank, make sure the power cord is plugged in and
fuses on the main controller are good.
Make sure that water ows to the unit. The heater will be running when the inlet water ow
sensor detects ow over 0.5gpm.
Make sure the cold and hot water pipes are not plumbed in reverse.
Make sure that water and gas supply lines are opened.
Make sure that water lines are not frozen.
Outlet water is not hot enough.
Make sure that the temperature setting on the unit is not too low.
Make sure that the lter in the cold water inlet line is not clogged with debris.
Make sure that the gas supply type is correct.
Check if the supply and manifold gas pressures are in accordance with specications.
Make sure that the water ow sensor with three wires has been properly connected on the
top of heat exchanger.
Outlet water is too hot.
Make sure that the temperature setting on the unit is not too hot.
Make sure that the lter in the cold water inlet line is not clogged with debris.
Make sure that the gas supply type is correct.
Hot water temperature
Make sure that the lter in the cold water inlet line is clean.
Check if the supply gas pressure is sufcient.
The blower is still operating after the
combustion stops. This is normal because the blower keeps operating for 3 minutes.
I can’t change the temperature
setting above 125°F on the Control
Panel.
This is a safety device to prevent scalding. Hot water temperature over 125°F can cause
severe burns instantly or death.
Abnormal sounds come from unit
during operation.
A leak of combustion gas between sealed chamber and exhaust duct inside the unit.
Improper venting termination, make sure that the venting termination complies with
specication.
Check if the supply gas pressure is sufcient. Insufcient gas pressure can cause unstable
burner ame and noise.

17
Troubleshooting
Diagnostics and suggested corrective actions
This controller is able to record information about the water heater condition at the time of the ten previous
faults or error. The control will display the following information.
Display Condition Diagnostic Corrective Action(s)
Nothing shown on
display and blower
running at full speed.
Control is not
receiving power.
Check wiring for short
circuit or incorrect wiring.
Correct wiring per wiring diagram.
Check for 14V output of
panel wire. Push the ‘A’ button of control panel.
Nothing is shown
on display and no
other Water Heater
components are
operating.
Control is not
receiving 120V
power.
Is there 120 Volts at the
manual switch?
Correct the power supply from the manual
switch.
Check the water heater
inside power manual switch.
Turn on the manual power switch inside the
water heater case.
Check for 120 volts at the
line voltage terminal inside
the water heater case.
Correct wiring inside the water heater case
using the wiring diagram in this manual.
Nothing is shown
on control panel, but
water heater is
operating.
Occurs when the
communication is
lost from the control
to the display.
Check for loose connec-
tions and proper pin
alignment/ engagement on
the Control's plug.
Check for continuity on the wire harness from
the display to the control panel. See repair parts
section for proper replacement part.
Cycle power off and on
using water heater power
switch and check for
operation.
Replace with new display module. See repair
parts section for proper replacement part.
TEMPERATURE
RISE TOO
QUICKLY
Occurs when supply
water temperature
in heat exchanger
rises faster than 2°F
per second during
the rst two
minutes the burner
is on.
Automatically resets after a
few minutes delay or use
manual reset.
See TEMPERATURE SENSOR and follow
procedures for loose connections.
TEMPERATURE
SENSOR
Occurs when a
temperature sensor
has electrically
shorted(SHORT) or
has become
disconnected
(OPEN).
Reset by pressing
the On/Off button
on the display.
Check all the temperature readings of the water
heater in the information menu to determine if
any sensors are currently displayed as SHORT
or OPEN.
Check wire harness for loose connections and
pin engagement at sensor Connection and
Control module.
If problem persists after checking items above,
replace Control.

18
Troubleshooting
Display Condition Diagnostic Corrective Action(s)
FLAME FAULT
Occurs when ame
is detected when
there should be no
ame
Reset using manual switch.
Reset screen on control
panel.
(Power button)
Burner may be operating too hot due to
incorrect combustion.
Check for ame at burner through observation
port with burner off. If ame continues after
shutdown, replace gas valve.
BLDC Fan FAULT BLDC Fan is unable
to reach required
speed or 0 RPM
when it is turned off.
Reset using manual switch.
Reset screen on control
panel.
(Power button)
Check wire harness for loose connections and
pin engagement at blower connections.
Water heater is in standby mode and fan is not
running. If FAN SPEED is not 0 RPM then
replace the fan.
IGNITION
FAULT
Water heater failed
to light after 10
attempts.
Reset using manual switch.
Reset screen on control
panel.
(Power button)
Check for spark through sight glass.
Check incoming gas pressure to water heater
when off and during ignition. Adjust within limits
on rating plate.
Check for vent pipe and intake pipe restrictions
or blockage
Check burner fasteners and gaskets
Check air intake pipe and orice
GAS VALVE
FAULT
The Control has
detected a problem
with its gas valve
output circuit
Reset using manual switch.
Reset screen on control
panel.
(Power button)
Check wire harness connections between gas
valve and Control.
If lockout reoccurs, replace Gas valve.