Low water cutoff sees no water.
1. Check low water cutoff. Is amber lamp fit?
Yes: Repair system piping, remove any remaining air in system
No: -> 2
2. Check low water cutoff. Is green power lamp fit?
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 plugges into 24Vac transformer? Is black/white harness plugged into 24volt harness?
Yes: -> 6
No: -> Insert harness
6. Disconnect blue/yellow harness from transformer. Using digital meter check for 24 Vac. Is 24 to 30 Vac present?
Yes: -> 7
No: -> 8
7. Connect harness to transformer. Disconnect harness from low water cutoff. Is 24 Vac at terminals 1 and 2 ( between blue and yellow wires)?
Yes: Replace low water cutoff
No: Replace harness
8. Disconnect black/white harness from transformer. Is 120 Vac measured at harness?
Yes: Replace transformer
No: Replace main harness