Problem with banging noises in Suprima 30 boiler

[Scorette]

I'm hoping someone here has some useful advice (that I can understand).

I have a Suprima 30 Boiler. It's coming up to seven years old.

When starting from cold it fires up, pilot light etc is on, and then there are a couple of loud bangs and it stops, the pilot light goes out. The bangs sound very much like there being air in the system.

The noise in the system started a few months ago when I had the valve in the shower replaced. Since then the shower doesn't drip and has kept it's temperature, but there was a much longer delay than before in the hot water coming through. Over time this has got worse and the shower would only start after running the hot water tap of the bath and then turning that tap off.

The pump/airing cupboard started making increasingly loud bangs and noises when it fired up. This could be stopped by manually switching the pump to position 2 rather than position 3. Dealing with the symptoms not the cause I realise but it worked. Again it sounded very much like air in the system.

I have bled all the radiators, upstairs and down, none of which had any air in and the water was clear.

In the last few days the amount of hot water/level of central heating has been decreasing and now it has stopped completely. The pump was still hot at this point, but clearly not pumping anything. I have turned it all off.

Questions are:
is there a way I can see if there is air in the boiler part, not just the radiators and fix it myself? (I'm okay at basic plumbing and electrics but nothing advanced)

Have I irreversibly damaged the pump and/or boiler by ignoring the problem?

What should I do now?

Many thanks for any advice you can give me.
Claire

 

[kevplumb]

undo the screw in the middle of the pump switch it on and see if the shaft turns

 

[Slugbabydotcom]

Is there a way I can see if there is air in the boiler part, not just the radiators and fix it myself? (I'm okay at basic plumbing and electrics but nothing advanced)

Only what kev just suggested you do. A dead pump warms up cos theres current running through it and it can be often mistaken as hot water from the boiler. Feel the pipe going into it and if thats cold you know for sure the pump is dead

Have I irreversibly damaged the pump and/or boiler by ignoring the problem?

Doubt it I reckon you have just witnessed the demise of your pump

What should I do now?

Get someone to check it out first just to be 100% sure then fit a new pump.
What I do is use a large screwdriver as a listening stick - Just a buzz = pump stuck - Whooshy noise = water flowing.
You could try it yourself but unless you have at least seen one done before are confident enough and have the right tools I would get a plumber as sometimes the valves on either side can leak necessitating a system drain down.[/quote]

 

[Scorette]

OKay, so I loosened the screw in the middle of the pump (dribbled some dark and danky water).

Put the heating on. Lots of gurgling. After some encouragement, pump happily spinning away on setting three, and gently on setting two. Nothing on setting one.

Pipe going into the pump is warm.

Did screw back up, pump now seems to be pumping. Still lots of gurgling going on, and pump sounds like it's working hard.

Pipes both sides of the pump are now hot.

I now need to go put the heating on (just did water, and whilst hot is coming out of the taps, I've had the emersion for a bit this morning, so don't know if it's the leftovers of that), and see what happens.

Thanks for the advice so far.

 

[croydoncorgi]

Pump's still on the way to the Great Pump Graveyard.

If it's jammed once, then it'll probably happen again. Problem is you still don't know (neither do we!) what caused it to jam in the first place. Wear due to running dry? normal wear and tear? contamination in system? air in system?

Before replacing the pump (probably only fixing a symptom), you should get the cause identified and fixed.