R
Rogerthedodger
I have an Ideal Minimiser SE50, installed 1999. Recently it was getting noisy when close to control-stat cutoff. I thought I’d try reducing the burner gas pressure. The manual says 3.5in wg, which must be set on commissioning. I hadn’t got that far into the manual when I installed the boiler, and it was OK for years. When I checked it it was more like 5.5in! Reduced it to 3.5in and it was OK, just a touch noisy but much better than before. So I reduced the pressure to 2.75in. After that it would sometimes (not always) fail to fire when called. It would always fire if the control-stat turned down to min, then up again. It’s not the control-stat as the fan runs, and it only runs when the control-stat calls.
As it seemed unlikely the lower pressure would cause the problem, I suspected the flame detector electrode so I removed the burner, checked the clearance and gave everything a good clean. Problem still there so I increased the pressure to 3.25in, and it’s been OK for a couple of days.
Anybody seen anything similar or can suggest anything? Maybe it does need a certain pressure to give enough initial flame for the detector, so if it recurs I’ll up it back to 3.5in. Or maybe the flame detector is dicky, and cheap enough to replace on the off-chance. Only other thing I can think of is PCB intermittent fault. If replacing was a sure cure I’d do it, but not keen as a test. Same only more so with the gas control valve. Gas pressure from meter is OK, about 9.5in.
As it seemed unlikely the lower pressure would cause the problem, I suspected the flame detector electrode so I removed the burner, checked the clearance and gave everything a good clean. Problem still there so I increased the pressure to 3.25in, and it’s been OK for a couple of days.
Anybody seen anything similar or can suggest anything? Maybe it does need a certain pressure to give enough initial flame for the detector, so if it recurs I’ll up it back to 3.5in. Or maybe the flame detector is dicky, and cheap enough to replace on the off-chance. Only other thing I can think of is PCB intermittent fault. If replacing was a sure cure I’d do it, but not keen as a test. Same only more so with the gas control valve. Gas pressure from meter is OK, about 9.5in.