Noisey Heating system, please help.

[plastic_peanut]

The majority of the t/static valves were opened fully. I have now opened the others to position 5. The boiler was on position 2. The pump was on position1 . I have just turned the central heating on, has been off for a couple of hours and i have put the pump to position 2. I will see when it starts making a noise and come back to you shortly.


I owe you a beer or five.

Thanks for your help.

 

[plastic_peanut]

The Boiler tripped out earlier on. I have reset it using the button underneath.
Would it be the water pump that caused it to trip because it got too hot??

Could a poor flow of water cause the noises because the boiler is getting too hot???

 

[noonespecial]

The Boiler tripped out earlier on. I have reset it using the button underneath.
Would it be the water pump that caused it to trip because it got too hot??

Could a poor flow of water cause the noises because the boiler is getting too hot???

The boiler trip could have been caused by the boiler getting too hot or the water flow rate through the boiler being inadequate.

What temperature setting is the boiler thermostat at?

Is the pump still on No. 2?

By turning the pump up to No. 2 this should have made the situation better not worse.

Do you radiators heat up ok? as it could be the pump is faulty.

If the pump is faulty this could be causing / aggravating the kettling.

The kettling is due either to

1. scale or some other deposits on the heat exchanger
2. a partial blockage within the heat exchanger from sludge or some other obstruction
3. poor water flow rate through the boiler.

 

[plastic_peanut]

Hello again,

The heating system is fine with regards the temperature and the control sytem. I had a look over it again this afternoon. The kettling noise is much quieter than it was before i drained and bled it last week. But the knocking noise is more apparent.

Originally, before we fitted the motorised valve the pipes would occasionally knock, but this was when the thermostat on the boiler was turned up. Turning it down, removed the problem so it was not an issue.

But now, regardless of the position of the boilers' thermostat it starts to knock after 10 minutes or so and stays there. I have tried all the settings on the pump but the pump just makes a grating noise in operation when in positions 2 or 3 and the water rate noticeably speeds up. The knocking then just becomes more frequent.


I have held the pipes in the airing cupboard and you can feel the knock throught them. But i am sure it is not fowling a joist etc. It seems to be pulsing from the boiler. Thats the best way to describe it.

Could it be air in the boiler causing the knocking????

Regards

James

 

[noonespecial]

The banging could perhaps be as a result of very severe kettling or it could be air.

When you first drained the system and chemically cleaned it, what was the condition of the water. Was there a lot of sludge?

When you carried out the subsequent clean what was the condition then?

Did you tip the heat exchanger and flush it through with a hose?

What I am thinking is that perhaps there is still muck within your heat exchanger?

Do the flow and return pipes from the boiler rise continuously from the boiler to allow the air / gas bubbles to flow freely?

Is the system open vented or sealed? If open vented does the flow pipe from the boiler rise continuosly ro the open vent?

If sealed have you got manual or automatic air vents on any high points?

Check that the pump is pumping in the correct direction by the arrow on the casing.

Check that the heating flow and return pipes from the boiler are connected to the correct connections on the boiler.

 

[plastic_peanut]

Hi Noones,

Thanks again for you replies. This evening I have removed the motorised valve from the 3-way. I have then adjusted it so that it feeds both the d.h.w and the c.h. This is how it was when we first moved in, as the motorised valve was removed. This has made the heating system quieter, removing the severe knocking, but still some lighter kettling and a more occasional lighter knock( nowhere near as aggressive).

I did re-fit the motor and tried it again on the central heating and the noises returned very quickly. So i removed it and left it as above. In the hope i may not be woken-up as early.

We used salamanda chemicals when we refilled the system. But i may purchase some more cleaners and try draining and refilling yet again.

Is there a way i can flush the boiler out and bleed it directly, other than from the radiators???

It is not a sealed system, it has the reservoir in the loft. This was originally caked in brown sludge and jelly. But i drained the water and cleaned out the tank a couple of days before the system was to be drained, so it did not make matters worse.

As for the vents, is this the pipe in the airing cupboard near the pump with a screw top??? This was also used to help bleed the system by releasing air out of it?? I presume this is a manual vent??

The water was quite sludgy the first time we drained it but the second seemed much better.

I didnt tip the exchanger and flush it through, what is the best way to do this??

The pipes do not appear to move noticeably, out of the top of the boiler. Is ths correct??

Hopefuly answered your questions.

Thanks again, i appreciate this

James

 

[noonespecial]

Hi Noones,

Thanks again for you replies. This evening I have removed the motorised valve from the 3-way. I have then adjusted it so that it feeds both the d.h.w and the c.h. This is how it was when we first moved in, as the motorised valve was removed. This has made the heating system quieter, removing the severe knocking, but still some lighter kettling and a more occasional lighter knock( nowhere near as aggressive).

This has reduced system resistance and thus increased water flow rate- I believe from this your main problem is water flow rate being inadequate. Perhaps faulty pump, incorrect pipework arrangement - can't say what exactly though.

Is there a way i can flush the boiler out and bleed it directly, other than from the radiators???

It is not a sealed system, it has the reservoir in the loft. This was originally caked in brown sludge and jelly. But i drained the water and cleaned out the tank a couple of days before the system was to be drained, so it did not make matters worse.

Now that is not good news-something was and probably is quite wrong-you may need a power flush rather than trying to do it yourself.

As for the vents, is this the pipe in the airing cupboard near the pump with a screw top??? This was also used to help bleed the system by releasing air out of it?? I presume this is a manual vent??

Yes- you should have these at all high points to enable you to vent the air out.

The water was quite sludgy the first time we drained it but the second seemed much better.

I didnt tip the exchanger and flush it through, what is the best way to do this??

As above I think you need system powerflushed really

The pipes do not appear to move noticeably, out of the top of the boiler. Is ths correct??

What I meant was to check the flow heating pipe is in fact connected to the boiler flow connection and not the return and vice versa

 

[plastic_peanut]

Thanks noonespecial for all your help. I am very greatful.

Best Wishes

James