Myson Apollo Fanfare Boiler not working

[dshipston]

Hi this is all new to me, so...

My heating hasn't worked properly for years, every year I get the boiler serviced and am told that it's burning efficiently, so have put the problem down to muck in the radiators which is keeping the downstairs rads cool/cold... hot water has never been a problem.

Recently, with winter closing in, I replaced the motorised valve above the pump and after a couple of loud bangs and cracks in the pipes, suddently I had ehating and hot water!! Great I thought, but yesterday, after about a week and a half, nothing

I noticed that the pilot light had gone out and became a real pain to relight (it ketp/keeps going out). I guess the obvious solution here is to replace the thermocouple, which I will today, but...

The pilot light did eventually stay on all evening, but the main burner on the boiler wasn't kicking in and out as it should have done - considering all of the raditators were cold!

On the odd occassion when the main burner did kick in, after about 10 seconds or so, it made a few loud cracks and bangs (coming from the boiler) and then went out again..thus not hot water getting up to the pump.

I'm thinking maybe the pump has had it, which is causing an insufficient flow of water through the boiler...could this be right?

If so, I guess the noise I hear is the water boiling and eventually causing a safety cutoff or something??

I have noticed that there are a few 'tinkling' nosies to be heard from the pump when you change speeds on it, almost as if there is some debrit going through it.

Any ideas?

Should I replace the pump? Or Hi & Lo thermostats? Or the pump overrun thermostat?

Any help would be appreciated.

Thanks

Dave

 

[cross thread]

change the pump as it sounds like its faulty ,but you should keep out of the boiler

 

[dshipston]

Will do...thanks

 

[dshipston]

Well, I've now fitted a new replacement pump (quite straight forward really) and a new thermocouple (easy to fit)...

..but we have the same problem!

When the pilot light stays lit, the boiler produces loud cracks and bangs as the main burner kicks in (presumable boiling the water), then about 5-10 seconds later, the main burner shuts down.

Every now and a gain, the pilot goes out which it hadn't used to!!

Any ideas?...Anyone? I'm desparate and cold

 

[joe-90]

One thing is clear, your water isn't circulating and is boiling inside the heat exchanger. I don't think it's a DIY job. Better call someone in before you need a new boiler.

 

[dshipston]

Could it be as simple as an air lock in the system?

 

[bster]

blockage\sludge or scaled HE - well thats what i've learned from this site

This is a question! - would measuring the flow pipe temp give a clue to the problem i.e - if its say 50 degrees instead of 85 degreesa would this indicate HE prob (if boiler was set to max and burners where lit)?

 

[urbanspaceman]

cold feed is blocked-leave to a proper heating engineer

 

[Agile]

Could also be a blocked or jammed pump valve!

Test by removing pump and openning each valve in turn into a bucket to see if you get a proper flow rate.

Could also be blocked pipework anywhere in the system or motor valves failing to open.

Tony

 

[dshipston]

Thanks for all of your replies..it's much appreciated!

The situation at the moment is this...

Thermocouple now keeps the pilot lit!
Hot water is good
Radiators...well they could be hotter, but at least they aren't cold!

One things for sure, the flow rate of water through the boiler probably isn't as good as it should be.

With the boiler set to 'Lo' I don't get the bangs and cracks from it that I did in the 'Hi' position - hence my theory on the reduced flow rate.

Next weekend I will try draining down the entire system in an attempt to flush out any loose muck. The only problem then is obviously I'll be adding air into the entire system and have to ensure that I bleed it all out!!(wish me luck).

Any advice as to how to force out or ensure there isn't any air in the system?

Or what the best practice is to flushing and re-filling a system?

thanks

Dave

 

[dee99]

I am having the same problem as you with regards to the banging, but this only happens when I put my programmer on "1 hour"...i.e to get HW or CH for 1 hour.

However since this began last sunday I have found that I can't get HW and CH at the same time...although the pipes in the cupboard for HW and CH are sometimes hot at the same time.

Any way I have had a couple of people come in to tell me various things from my boiler needing to be descaled, pumping problem and a problem with a valve in my cuoboard near the pump.

I get the feeling they don't really know so now I am considering just replacing the boiler system which is about 16 yrs old (Myson Apollo Fanfare 15/30) and having a flush so that i know once and for all that its all ok.