Potterton Suprima 40 boiler Fault

[cassman]

I have already had a search of previous posts and read a great deal about the PCB's with their dodgy solder joints but can't find a direct match to my symptoms.

My fault is this. Whether I have H/W or C/H selected the boiler will ignite but only for a few seconds before the red LED flashes on. I then end up with the red one solid and the green one flashing.

This fault occurred for the first time just over a week ago. My finding out was a cold shower. My initial thoughts were for the pump not giving me any flow to heat my water tank. The pump was quite hot at the time, I removed it, ran it okay, checked the housing for things that could jam rotor and refitted. System worked fine.......... for 4 days.

Same thing happened so I went through the same procedure and once again system worked fine........... for 4 days until this morning.

I went through the same thing this morning without success. I have also engaged the manual reset knob on the pump with the rotor and can see that the pump is turning.

Somebody at work thinks I may have an air lock? Is this likely and if so how do I vent it? Any help appreciated.

 

[Agile]

It does sound like a lack of flow!

Probably better to change the pump! It may well be running slow.

Do you vent the pump by wobbling the loose black knob nut? They are usually pretty self venting though.

Tony

 

[cassman]

Yes I used the black knob on the front to vent and heard the air rise and leave via the top up tank in the loft.

One thing that did strike me as odd - should I be able to stop the pump by hand.

An hour or so after my original posting the boiler struck up on its own and has been working fine all day but I just know it will fail again within the week. I may well just change the pump to see what happens.

 

[croydoncorgi]

You haveto ask yourself the question: why is the pump jamming?

Chances are it's got black sludge in the water-lubed bearing and it's scrap.

Put in a new pump and if you don't fix the sludge problem, it'll soon be scrap too.