Heatslave 26/32 Burner/air issue

[oilhead]

The starting point for any oil burner setting is matching the manufacturer's settings for nozzle and oil pressure. These are the constants of fuel for the required output for the boiler. The air setting can never be stipulated as it varies with flue conditions. You have raised, inadvertantly, another option to your problems. What photocell do you have fitted? The Sterling burner usually comes with an FZ 80mm photocell, but for some reason, Worcester only ever used the shorter one as used on B9 and B11 burners. With the short photocell, any hint of overairing tending towards 'blue flame' combustion, will make the flame difficult to 'see' with the short photocell. This may be why the burner ran under supervision of a lamp light, but not in the burner, although you could see a flame it may not be of the correct intensity.

 

[john975]

unsure of the part number, however it is the same length as the old one as the old one is still here and the plumber showed me the old one compared to the new one.

 

[gigz]

unsure of the part number, however it is the same length as the old one as the old one is still here and the plumber showed me the old one compared to the new one.

But is the old one the original ? In the past i've took parts out and swapped like for like only to find its the wrong part.

 

[oilhead]

Old brains not working. Should have said MZ photocell. Most people on here will probably never have seen an FZ.

 

[john975]

unsure of the part number, however it is the same length as the old one as the old one is still here and the plumber showed me the old one compared to the new one.

But is the old one the original ? In the past i've took parts out and swapped like for like only to find its the wrong part.

it was the original photocell, boiler has not been touched in 8 years. I recon the plumber knacked up on the setting or he tried to up the air settings higher to attempt to compensate for the flue issue. Boiler is running now but probably not at best settings and silver box is off.

 

[john975]

ok so the boiler is running. However there is still a flue issue. I helped install the flue 8 years ago with my uncle. At the bottom of the boiler there is a metal plate in between the start of the flue and the actual boiler. Exhaust fumes go up the middle round pipe and clean air gets drawn into the boiler from the square flue. the narrowest point is the plate were boiler meets flue.The plates there to separate the air from the fumes. Were the plate sits there is what looks like a deposit/crystallisation, if that's inside the plate then I am guessing that's the blockage.

I had the install instruction for the flue in paper format, does anyone no where I can get the pdf instructions, as I have lost my paper copy. (looking for a quick way to clean the inside of plate without full flue disassemble and details of how the plate comes off.)

I think the crystallisation is caused by water deposits/condensation running down the air intake of the flue.

 

[Burnerman]

Have you looked at 'Worcester oil boilers manuals'.......discontinued products?
All the Heatslave info is there, ready to download.
John

 

[john975]

I could not locate it on the WB site . I think the part number is 7716190003

 

[Burnerman]

If it's the photocell you are talking about, I'm pretty sure it's a MZ770.
The original part number is 8716 156 692 0.
John