Got called to a Greenstar 42CDi with EA code.
checked flue -ok
checked condensate - ok
checked for gas etc - ok
17.54 Mbr (advised MI's requested min 18Mbr inlet mop) - low
checked ionisation probe looked like a cocktail stick that worn 9.5yrs and not been checked before! Changed and EA sorted cleaned out exchanger (never seen so much build up in a Worc before) changing seal checked burner changed seal all good, set ratio to 9.7% max 9.1% min then normal checks etc.
2.5 hrs later got a call about noise! checked fan pressure wanted >-4.8mbr had -5.4mbr
isolated and and returned next day leaving heaters, late one.
re-checked ratio max was sitting at 8.9/9% with adjustment wound all out. Fan pressure same -5.4mbr.
changed the gas valve calibrated ratio etc noise gone, I discovered the gas valve had been changed 2.5yrs earlier.
mine had had it but would be worth checking not drifted too far on max and min ratio as low burn/min will cavitate like a git.
hope this helps somebody.
checked flue -ok
checked condensate - ok
checked for gas etc - ok
17.54 Mbr (advised MI's requested min 18Mbr inlet mop) - low
checked ionisation probe looked like a cocktail stick that worn 9.5yrs and not been checked before! Changed and EA sorted cleaned out exchanger (never seen so much build up in a Worc before) changing seal checked burner changed seal all good, set ratio to 9.7% max 9.1% min then normal checks etc.
2.5 hrs later got a call about noise! checked fan pressure wanted >-4.8mbr had -5.4mbr
isolated and and returned next day leaving heaters, late one.
re-checked ratio max was sitting at 8.9/9% with adjustment wound all out. Fan pressure same -5.4mbr.
changed the gas valve calibrated ratio etc noise gone, I discovered the gas valve had been changed 2.5yrs earlier.
mine had had it but would be worth checking not drifted too far on max and min ratio as low burn/min will cavitate like a git.
hope this helps somebody.