Raypak 135A - Manual (Page 20)

20
5. TROUBLE SHOOTING GUIDE
IMPORTANT NOTICE
These instructions are primarily intended for the use of qualified personnel specifically trained and experienced
in the installation of this type of heating equipment and related system components. Installation and service
personnel may be required by some states to be licensed. Persons not qualified shall not attempt to install this
equipment nor attempt repairs according to these instructions.
PROBLEM(S)
1)When tankstat is turned on, heater
does not operate.
2)When tankstat is calling for heat,
pump is on, but burners will not turn
on.
CAUSE(S)
1)No power to the heater.
2)Defective tankstat or disconnected
wire in thermostat circuit.
3)Defective transformer.
1)For Standing pilot models pilot burner
not lighted.
2)If pilot burner will not stay lighted,
thermocouple or gas valve may be
defective.
3)Gas knob in "Pilot" position.
4)Vent switch is open.
5)Roll-out switch is open.
6)Manual Reset High limit is open.
7) Fast Response Temperature
Sensor probe is defective.
8) Fast Response Temperature
sensor board is defective.
9 ) Defective ignition module or
defective gas valve.
SOLUTION(S)
1)Check circuit breakers, disconnect
switch. Make sure power is on.
2)Check continuity on thermostat and
wiring circuit. Replace thermostat, or
repair wiring connections.
3) Check secondary voltage. If no 24V,
replace transformer.
1)Light pilot burner. (Follow lighting
instructions on rating plate).
2)Check thermocouple MV generation.
If less than 25MV (open circuit), re
place thermocouple. If between 25-
35 MV, replace gas valve.
3)Turn knob to "ON" position.
4) Check for blockage of venting system
or disconnected vent piping. After
problem is corrected push button to
reset vent switch.
5)Check for blockage of flue or sooted
heat exchanger. After problem is
corrected push button to reset roll-out
switch.
6)Check water flow and adjust to
obtain 8° to 10°F temperature rise.
7)Red LED on circuit board will be ON
to indicate a loose sensor connection
or a shorted sensor. Check terminal
connectors or replace sensor as re-
quired.
NOTE: Red LED will also be ON if
sensor temperature exceeds 300°F or
drops below - 20°F. It will turn OFF
when sensor temperature returns to the
proper range. Yellow LED will be ON, if
temperature exceeds 210°F. When ei-
ther Red or Yellow LED is ON, heater
will be shut down.
8)Check voltage across output and
common terminals. If no 24V is pres-
ent, replace board.
9)On Honeywell module, check voltage
across terminals MV and MV/PV. If
no 24V is present, replace module. If
24V is present, replace gas valve.