Low water cutoff.
1. Check low water cutoff. Is amber lamp it?
Yes: Repair system piping, remove any remaining air in system and refill.
No: -> 2.
2. Check low water cutoff. Is green power lamp lit?
Yes: -> 3.
No: 5.
3. Is harness plugged into control module J16?
Yes: -> 4.
No: Insert harness.
4. Disconnect harness from low water cutoff and control module J16. Check continuity if harness. Harness ok?
Yes: Replace low water cutoff.
No: Replace harness.
5. Is harness plugged into low water cutoff? Is blue/yellow harness plugged into 24 Vac transformer? Is black/white harness plugged into 24 volt harness?
Yes: -> 6.
No: Insert harness.
6. Disconnect blue/yellow harness from transformer.Using digital meter check for 24 Vac. Is 24 to 30Vac present?
Yes:-> 7.
No: -> 8.
7. Connect harness to transformer. Disconnect harness from low water cutoff. Is 24 Vac at terminals 1&2?
Yes: Replace low water cutoff.
No: Replace harness.
8. Disconnect black/white harness from transformer. Is 120 Vac measured at harness?
Yes: Repalce transformer.
No: Replace main harness.