C
CM25
Hi guys,
I'm after some help on a commercial site we look after for a housing association.
Problem:
All 3 modules locking out on main burner ignition segment of indicator dial intermittently but persistently ( almost all daily now but has been getting worse).
Checked: everything
Replaced both ionisation and spark electrode
Checked and cleaned burners (and seals) new burners on order but existing appear ok
Checked current on new ionisation probes 2-10 micro amps on pilot and apart from when main burner fails over 40-50 micro amps, when fails it drops out on less than 20(which is what it should do) this proved probably with flame not rectifying/sticking to burner)
Checked and set differential burner pressure (2.5mb)
FGA all between 9.2-9.5 co2 all under 50ppm (mi = 9-10 co2 max 300 ppm 2.5 bp)
Checked draft pressure as suspect fault caused by flame lift, and had at times 0.14mb draft (mi = max 0.1mb)
Draft stabiliser fitted, after speaking to manufactures tech flue specialists has been decided that this ok to be left in permanent open position,
Flue is fine can see all the up (approx 5-6m high) and all the way through horizontal section approx 1.5m
Checked working inlet at meter 21mb
No inlet test points on gas valves or on gas train beneath altho I'm goin back to drill one in gas supply is 2" steel. Managed to do a sort or inlet test of the pilot solenoid as it's mains pressure with 2 of 3 running (not the one I was testing from) had 21mb so I'm sceptical to say least that it's a problem with gas.
Have spoken to a senior tech at Hamworthy twice and have checked everything I possibly can
Proper head scratcher so any help would be great
I'm after some help on a commercial site we look after for a housing association.
Problem:
All 3 modules locking out on main burner ignition segment of indicator dial intermittently but persistently ( almost all daily now but has been getting worse).
Checked: everything
Replaced both ionisation and spark electrode
Checked and cleaned burners (and seals) new burners on order but existing appear ok
Checked current on new ionisation probes 2-10 micro amps on pilot and apart from when main burner fails over 40-50 micro amps, when fails it drops out on less than 20(which is what it should do) this proved probably with flame not rectifying/sticking to burner)
Checked and set differential burner pressure (2.5mb)
FGA all between 9.2-9.5 co2 all under 50ppm (mi = 9-10 co2 max 300 ppm 2.5 bp)
Checked draft pressure as suspect fault caused by flame lift, and had at times 0.14mb draft (mi = max 0.1mb)
Draft stabiliser fitted, after speaking to manufactures tech flue specialists has been decided that this ok to be left in permanent open position,
Flue is fine can see all the up (approx 5-6m high) and all the way through horizontal section approx 1.5m
Checked working inlet at meter 21mb
No inlet test points on gas valves or on gas train beneath altho I'm goin back to drill one in gas supply is 2" steel. Managed to do a sort or inlet test of the pilot solenoid as it's mains pressure with 2 of 3 running (not the one I was testing from) had 21mb so I'm sceptical to say least that it's a problem with gas.
Have spoken to a senior tech at Hamworthy twice and have checked everything I possibly can
Proper head scratcher so any help would be great
