50
Rinnai Tankless Water Heater Installation and Operation Manual
* See “Electrical Diagnostics” on Technical Data
Sheet located on inside front cover of water heater.
12
No Flame
•
Check that the gas is turned on at the
water heater, meter, or cylinder.
•
Check for obstructions in the flue outlet.
•
If the system is propane, make sure
that gas is in the tank.
•
Ensure gas line, meter, and/or regulator
is sized properly.
•
Ensure gas type and pressure is
correct.
•
Bleed all air from gas lines.
•
Ensure proper venting material was
installed.
•
Ensure condensation collar was
installed properly.
•
Ensure vent length is within limits.
•
Verify parameter setting are set
properly.
•
Check power supply for loose
connections.
•
Check power supply for proper voltage
and voltage drops.
•
Ensure flame rod wire is connected.
•
Check flame rod for carbon build-up.
•
Disconnect and reconnect all wiring
harnesses on unit and PC board.
•
Check gas solenoid valves for open
circuits.
•
Remove burner plate; inspect burner
surface for condensation/debris.
14
Thermal Fuse
•
Check for restrictions in air flow around
unit and vent terminal.
•
Check gas type of unit and ensure it
matches gas type being used.
•
Check for low water flow in a circulating
system causing short-cycling.
•
Check for foreign materials in
combustion chamber and exhaust
piping.
•
Check heat exchanger for cracks or
separations.
•
Check heat exchanger surface for hot
spots which may be caused by scale
build-up. Refer to instructions in manual
for flushing heat exchanger. Hard water
must be treated to prevent scale build
up or damage to the heat exchanger.
•
Measure resistance of safety circuit.
•
Ensure high fire and low fire manifold
pressure is correct.
•
Check for improper gas conversion of
product.
16
High Outgoing Temperature
•
Check for restrictions in air flow around
unit and vent terminal.
•
Check for low water flow in a circulating
system causing short-cycling.
•
Check for foreign materials in
combustion chamber and exhaust
piping.
•
Check for blockage in the heat
exchanger.
•
Check the thermistor sensor and clean
sensor of scale build-up.
19
Electrical Grounding
•
Check all components for electrical
short.
32
Outgoing Water Temperature Thermistor
•
Check sensor wiring for damage.
•
Measure the resistance of the sensor.
(See Electrical Diagnostics)
•
Clean sensor of scale build-up.
•
Replace sensor if necessary.
33
Heat Exchanger Thermistor
•
Check sensor wiring for damage.
•
Measure resistance of sensor. (See
Electrical Diagnostics)
•
Replace sensor if necessary.
