Potterton Promax Boiler Airlock
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Kylie
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Potterton Promax Boiler Airlock

by Kylie » Fri Feb 01, 2008 10:54 pm

okay, this is a long story, but please bear with me...

Summer 2006 my boiler broke down... we left it till it started to get cold before we fixed it. Turned out we apparently needed a new ignition pcb. We replaced it, and had the system bled and all was well.... or so we thought.

Last November everything stopped working again... in comes plumber number 2. He replaces the pump, after identifying that it had seized, and tried to test a few things on the boiler. After lots of running up and down to the emmersion tank, it seems to be sorted. Nice and warm. But 2 days later its broken again.

Eventually we manage to get another plumber - having been let down by plumber number 2. They come in, do a powerflush on the useless microbore system we have, and fiddled with the boiler, changed ignition PCB again, changed the flow switch sensor, and the two temp sensors that are in the top of the boiler.

Still no joy. After about 30 seconds of being on, the boiler locks out and shuts down. The pump is still trying to work... but the ignition won't come on again.

Plumber number 3 came out again yesterday and said that it must be the heat exchanger is limescaled up and is giving a false reading... meaning that the limescale is getting hotter than the water in the pipes, so the temp sensor thinks it is hot enough and then cuts the boiler out.

My partner didn't think this would be the case and signed up for one of the manufacturers engineers to come out, who has told us there is an airlock in the system.

Now we really don't know what to believe. Do we need a new heat exchanger, new boiler, or do we have an airlock!?

If we have an airlock, how the hell do we get rid of it?!?

Please help, the 3 months of using oil filled rads is costing me a fortune :(

htg engineer
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by htg engineer » Sat Feb 02, 2008 10:58 am

It seems that the 'heating engineers' if you can call them that. Are just throwing parts at your boiler - at your expense. 2 pcb's in 2 years - bet they weren't cheap. Hoping that it will fix the problem.

It might just be me that thinks this but....... If you pay a heating engineer to fix your boiler - you expect it to be fixed.

"They come in, do a powerflush on the useless microbore system we have, and fiddled with the boiler, changed ignition PCB again, changed the flow switch sensor, and the two temp sensors that are in the top of the boiler"

Once they'd left and the boiler went off, what did you do ? - you should have got them back again and again and again. You paid them to fix the boiler - which they failed to do and still charged ?

The manufacturers engineers - should be right. So I would go with the airlock theory. You could try draining down the system and re-filling. Vent all radiators, open any auto airvents and bleed any manual vents.

Let me know how you get on.

Kylie
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Joined: Fri Feb 01, 2008 10:42 pm

by Kylie » Sat Feb 02, 2008 10:10 pm

Thanks for your reply... I called him today and he agreed to pay back the money for the temp sensors as they didnt need changing. He's also going to drain and refill the system.

Thank goodness... we will see tomorrow evening if its fixed. I'll update you as to how we get on.

Just sick and tired of being so cold... we've all been ill as a result.

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