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) | CAUSE(S) |
1)When tankstat is turned on, heater | 1)No power to the heater. |
does not operate. |
|
| 2)Defective tankstat or disconnected |
| wire in thermostat circuit. |
| 3)Defective transformer. |
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.
2)When tankstat is calling for heat, pump is on, but burners will not turn on.
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.
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.
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 sys tem 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
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 either Red or Yellow LED is ON, heater will be shut down.
8)Check voltage across output and common terminals. If no 24V is present, 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.
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