Keston C36 Boiler noise

[humbleton]

I posted a reply in an old topic, see the last post in
//www.diynot.com/forums/viewtopic.php?t=88214&highlight=

But got no reply so posting as new topic. I'd be very grateful for any help on this.

Cheers

 

[Agile]

You should not have done that as it was not "your" thread.

But you should have explained your problem here on your own thread!

This is what you had said!

I have a similar problem to this, although my jet engine takes off mainly when CH switches on first thing in the morning. It's just out of guarantee, so I'm loath to call someone out if it's a simple fix. I had someone called out a while back when it was making a noise and he said pressure was too low and lo and behold it got rid of noise. He also said there was some kind of bug in the chip and pressure reading could be 0.5 bar out! Since then I've always kept it up to about 1.7 bar, but I do have to frequently top it up. The other thing it does, which is pretty scary, is 'explode' sometimes when switching on for CH or water. Enough to make you stand back when you know it's coming on! This seems to happen when boiler temperature is low.

I'd be grateful if anyone can enlighten me on what's going on, via these questions:

1. If pressure is ok, what else could be causing the noise? I live in an area of quite high limescale, if this is the problem, what's the best way of cleaning it out?
2. Should I be concerned about regular topping up. On average about every couple of months.
3. What's causing those explosions?

Thanks in advance, Rob

 

[Agile]

It seems as if it was not professionally installed by a CORGI who had checked the combustion settings at installation.

It also seems as if you have not had it properly serviced anually either ( which is an annual requirement to extend the warrantee ).

Until it has been properly checked by a competent engineer who must have a Flue Gas Analyser ( FGA ) then its not possible to guess at any fault.

The days of doing boiler repairs with a few spanners are over. Now a multimeter, digital manometer and an FGA are required.

Tony

 

[humbleton]

I added it to that thread as it was a related problem and didn't want to unecessarily pollute the thread space.

Installed by CORGI engineer, serviced by, hopefully competent, BG engineer last November. Seem to be noticing the noises more, recently though, dare I say it, since it was serviced!

 

[Agile]

The question arises did he use a Flue Gas Analyser to commission and to service?

Only about 5% of CORGI registered people have them.

Its like a big multimeter with long tubes which are pushed into holes in the boiler or flue!

BG dont usually "service" boilers! All they do is a safety check using an FGA. If its safe ( CO below 0.004 ? ) then they dont do any more!

A friend of mine services Vaillant Ecotecs without an FGA "because he needs the £75 money". But he is unable to check the combustion characteristics or change/inspect the combustion chamber seals.

Tony

 

[humbleton]

Doubt v much if he used an FGA. So assuming BG used an FGA and all was ok, where do I go from here? Do you reckon BG Homecare 100 is worth doing, costs £11.70 a month?BG

 

[Agile]

Your problem is often caused by the combustion characteristics not being set up correctly.

The CO level has no significant bearing on the weak mixture your boiler may well have. So it could be "safe" in BG terms but still be incorrect and make a noise.

There is another aspect that would be covered on a proper service. That is to inspect and check the spark gap on the ignition electrodes.

Tony

 

[simond]

My best advice would be not to fit a keston.

Since you already have one, you will find a maintenance contract extremely good sense. Don't use up all your holiday allowance, you'll need a few days each year to wait in