2008 Central Heating not working

[fakinsupa]

Hi guys im NOT a plumber lol. Our central heating system broke down about 2 months ago. Recently 2 engineers said I have a blockage and need to flush the system. The problem we had was that the boiler keeps cutting out and it appears there is no water getting into the rad's upstairs.

I have today hired a flushing machine and have started the process, however, although all rad's now appear to have water in only 3 out of 4 get hot upstairs and none get hot down stairs.

Also the pipe from the flush machine to the system appears full of water while the return pipe appears empty. If I reverse the flow on the machine then again the pipe into the system is full but gain the return is empty. It appears as so there is no presure on return.

Does this mean I do have a blockage and if so will the flush machine sort it out? or does an body have any other ideas?

Cheers

 

[sonray ltd]

i know you say your not a plumber, and i don't exspect you to know everything.
you are clearly wasting your money on hiring the powerflusher.
powerflushing don't work on pressure it works on flow rate.

to powerflush your system to a descent standard you'll need to be able to operate all the radiator valves, isolate the hw circuit from the heating curcuit, shut all apart from one radiator at a time to powerflush the heating curcit, isolate or loop the f/e pipes.

if you just flush your system without isolating the hw circuit and each rad you will be just sending the water round the same route and the quickest route.

also not using the right chemicals for the right system can cause damage and not flushing the chemicals fully can cause damage.

thats why powerflushing is not a cheap job to get done for what is involved.

 

[fakinsupa]

i know you say your not a plumber, and i don't exspect you to know everything.
you are clearly wasting your money on hiring the powerflusher.
powerflushing don't work on pressure it works on flow rate.

to powerflush your system to a descent standard you'll need to be able to operate all the radiator valves, isolate the hw circuit from the heating curcuit, shut all apart from one radiator at a time to powerflush the heating curcit, isolate or loop the f/e pipes.

if you just flush your system without isolating the hw circuit and each rad you will be just sending the water round the same route and the quickest route.

also not using the right chemicals for the right system can cause damage and not flushing the chemicals fully can cause damage.

thats why powerflushing is not a cheap job to get done for what is involved.

Thanks for the reply. The instructions above is what I have been doing. What are the f/e pipes?

Should both pipes in and out of the power wash have the same flow of water?
cheers again

 

[sonray ltd]

feed / expansion pipes in the loft, or you'll end up with a flooded loft.
when you place the pipes on to where ever your fitting your machine the water from the system will fill the machine then when you turn your machine on the level will drop in the container, so open your mains cold feed to the unit and keep it topped up,
when its reached its level shut the mains hose.

what instructions ?
what have you done just let the water flow round system ?

 

[fakinsupa]

feed / expansion pipes in the loft, or you'll end up with a flooded loft.
when you place the pipes on to where ever your fitting your machine the water from the system will fill the machine then when you turn your machine on the level will drop in the container, so open your mains cold feed to the unit and keep it topped up,
when its reached its level shut the mains hose.

what instructions ?
what have you done just let the water flow round system ?

Yes I have blocked them of (f/e pipes) I have flushed all the rad's now 1 by 1 but I can't get 2 of the rads hot at all. I have flushed these 2 and dumped the water then reflushed them again but they will not get hot or even warm.

Any idea

I have now turned the flush machine off but left the pipes attached. When I bleed one of the rad's that will not get hot/warm it is sucking air in. Any idea why and could this be my problem why it will not get hot

 

[sonray ltd]

where these to rads ok before you touched the system ?
when you say the machine is still attached and the rads are not getting hot, is by means of running the boiler or from the flushing unit ?
how have you connected the machine to a rad or pump etc ?

 

[fakinsupa]

where these to rads ok before you touched the system ?
when you say the machine is still attached and the rads are not getting hot, is by means of running the boiler or from the flushing unit ?
how have you connected the machine to a rad or pump etc ?

I have contected the machine to the pump. I have added a sludge remover and followed the instructions that came with the pump (the same instructions you said) These rad's were part of the rad's that would not get hot. I have now got all the rad's working except these 2 to which are on a inverted pipe loop (if that makes any diff) one up stairs and the other below down stairs.

I have closed all valves on rad's except the one in bathroom (hand towel type) and flused and dumped and flushed ect (so poss no more sludge remover left?) I have also taken the rad of the wall and cleaned. It was very very black. I also checked the other rad that don't get warm or hot and the water is clear. I have just started to flush again after cleaning rad but again the boiler went off after about 3 mins and the rad is cold.

I don't know if it makes a difference but when I flush the system in reverse the rad expells air. When I flush normal it draws air into the rad?

Any ideas and thanks very much for the advice

Just one more thing if it helps. Only one pipe on the bolier gets hot the other is cold when flushing this rad?

 

[sonray ltd]

>I don't know if it makes a difference but when I flush the system in reverse the rad expells air. When I flush normal it draws air into the rad?


this rad does the water circulate when running the flusher ?
cause to me it sounds like their is still a blockage in the pipe somewhere.

 

[fakinsupa]

>I don't know if it makes a difference but when I flush the system in reverse the rad expells air. When I flush normal it draws air into the rad?


this rad does the water circulate when running the flusher ?
cause to me it sounds like their is still a blockage in the pipe somewhere.

I know this might sound daft but how can I tell if the water is circulating through this rad?

Would it help if I put another sludge remover in? and do you think the flusher will sort the block out or will it be a matter of floor boards up job lol

 

[sonray ltd]

when you run the flusher and only this rad open etc the pump will pump the water out is the water returning in the other pipe ?

or disconnect the flusher and re-connect it to that rad.
what chemical did you use ?

 

[fakinsupa]

when you run the flusher and only this rad open etc the pump will pump the water out is the water returning in the other pipe ?

or disconnect the flusher and re-connect it to that rad.
what chemical did you use ?

When I flush it in reverse there is a very good return of water into the machine. When I flush it normal the return water is not very much?

The sludge remover is norstrom prochem sludge remover?

If I connect it to the rad will I need to reconnect the pump? and again I know this sounds daft but do you mean attach it to the rad or to the pipes supplying the rad?

Should I try another sludge remover first sounds easier lol

 

[sonray ltd]

>When I flush it in reverse there is a very good return of water into the machine. When I flush it normal the return water is not very much?

that don't make any sense. even worse that you say in the flow its restricted, in return its good.

what boiler is on your system ?
this rad has it ever worked ok or always been a problem?

if you connect to the rad valves removing the rad. put the pump back.

i always use sentinel products sentinel x800 when using a flusher.

that flow problem i can't get my head round why its ok one way not the other.
someones not stuck a non return valve in the pipework to that rad by any chance ?

 

[fakinsupa]

>When I flush it in reverse there is a very good return of water into the machine. When I flush it normal the return water is not very much?

that don't make any sense. even worse that you say in the flow its restricted, in return its good.

what boiler is on your system ?
this rad has it ever worked ok or always been a problem?

if you connect to the rad valves removing the rad. put the pump back.

i always use sentinel products sentinel x800 when using a flusher.

that flow problem i can't get my head round why its ok one way not the other.
someones not stuck a non return valve in the pipework to that rad by any chance ?

The boiler is a potterton and is about 15 years old. The rad's have been working. I did fit the hand rail rad myself using plastic push fit and flexi hose upto the rad. I think I may of used the connectors that you turn with a screwdriver to turn the water on/off. If i have used non return valves though would the rad's not have worked in the first place?

 

[sonray ltd]

ok we seem to be getting somewhere now.

this flexi hose you used is not one of these is it ?

http://image.bizrate.co.uk/resize?sq=160&uid=342062898&mid=82610

if you have used non return valves they will give you flow one way not the other unless they stick and can give you flow bothways.

 

[fakinsupa]

ok we seem to be getting somewhere now.

this flexi hose you used is not one of these is it ?

[DLMURL]http://image.bizrate.co.uk/resize?sq=160&uid=342062898&mid=82610[/DLMURL]

if you have used non return valves they will give you flow one way not the other unless they stick and can give you flow bothways.

Yes it is, oh dear i guess that is a problem then lol. If I have used non return vales would the system not have worked in the first place

 

[sonray ltd]

i don't think you have used non return valves as they don't have a screwdriver fitting.

as for the flexi they are not designed for heating systems.
most are only approved up to 65 degrees and not constant.
your heating system runs hotter and they collapse inside after time.

 

[fakinsupa]

when you run the flusher and only this rad open etc the pump will pump the water out is the water returning in the other pipe ?

or disconnect the flusher and re-connect it to that rad.
what chemical did you use ?

Thanks very much for your help. After your advise I have ripped up my ties in the bathroom lol and changed the flexi hose. I had not plumbed it in properly as well I think. So all plumbing done correct now.

Except I have flushed the system and the water is clear. Each rad got hot. So I have taken machine back but now only the rads up stairs work could this now be down to balancing? or would you have any other suggestion? ie pump

Infact only 2 rads work up stairs and none down stairs?

 

[sonray ltd]

i take it your pump/motorised valves are upstairs.

how many rads upstairs ?
how many downstairs ?
has any of the rads got trv's

is this how its been since you flushed it or have they been hot now gone cold ?

 

[fakinsupa]

i take it your pump/motorised valves are upstairs.

how many rads upstairs ?
how many downstairs ?
has any of the rads got trv's

is this how its been since you flushed it or have they been hot now gone cold ?

Yes the pump/motorised valves are upstairs.

3 rads and 1 towel rad upstairs.
3 rads down stairs
none of the rads have trv's attached

All the rads were working fine then the boiler kept cutting out every few min's. Engineer came out replaced loads of things in boiler then said we must have a blockage. We called another and he said the same. I have flushed the system as instructions and the water is clear. The rads down stairs are full of water and bleed clear water. We did try and bleed off loads of water last night on one rad down stairs and that appeared to draw warm water into the down pipe to the rad. We can get all rads working upstairs but none downstairs. We have closed all rads up stairs but still no heat down stairs.

Any ideas?

 

[Mike Jackson]

Are the downstairs rads on individual drops or on one circuit? What size is the pipework to the downstairs rads?

It could be air locks in the system or the powerflush could have moved some debris and caused a blockage elsewhere in the system.

If your on individual drops it's easier to figure out where the problems are? Shut off one valve to a rad and open the air vent to check that water comes out and doesn't stop. Repeat this with the other valve. If the water stops when one side has been opened there is a blockage or air lock to this pipe. If it's okay with both valves the problem is elsewhere.

One other thing occurs to me. Have you checked the pump is working and fitted the correct way round? If the pump is not working you will quite often find that the upstairs rads will heat by gravity but the downstairs stay cold.

Mike

 

[fakinsupa]

Are the downstairs rads on individual drops or on one circuit? What size is the pipework to the downstairs rads?

It could be air locks in the system or the powerflush could have moved some debris and caused a blockage elsewhere in the system.

If your on individual drops it's easier to figure out where the problems are? Shut off one valve to a rad and open the air vent to check that water comes out and doesn't stop. Repeat this with the other valve. If the water stops when one side has been opened there is a blockage or air lock to this pipe. If it's okay with both valves the problem is elsewhere.

One other thing occurs to me. Have you checked the pump is working and fitted the correct way round? If the pump is not working you will quite often find that the upstairs rads will heat by gravity but the downstairs stay cold.

Mike

Thanks for this. Yes we are on individual drops so I will explore the valve check.

The pump sounds like it is working but could it still not be working fully?

I have now done the check on the rads from the down pipes. I bled the rad on ech valve for about 30 sec. Water was constant and straw like colour in each rad. The only thing to add is that one lot of down pipes feed 2 rads if that would make any diff.

I now assume after this test that I have no blockage and no airlock? Does this mean it will come down to Pump or balancing? As the bolier has been trying to work all day it only comes on for about 5-10 mins then cuts off?

 

[Mike Jackson]

If the downstairs rads don't work when the upstairs are shut down it can't be balancing. Only really leaves the pump. Make sure the pump valves are fully open and ensure that it's the correct way round before forking out for a new one. I've had the shaft fail on a pump so that the motor was spinning but the impeller was only going round slowly.

Mike

 

[fakinsupa]

Ok so now I am tearing my hair out.

I have shut all rads upstairs. One of the down stairs rads is hot and 1 off the down pipes feeding the other 2 rads are hot but not the rads or the return pipe

We had C/H off all day only running H/W. So I shut all the up stairs rads then turned hot water off and C/H on. I would have thought that the boiler would have then stayed on until the down stairs rads were hot, however, again the boiler only stays on for 2-3 mins then goes off then comes back on after 2-3 mins.

So is it still poss that it is balancing or pump or something else

 

[sonray ltd]

its poss it could be a pump but i don't think so.
balancing not an issue at the moment. not with only two rads open.
the boiler will cycle like that at the moment with only one rad circulating.
as the water is not really dropping in temp on one rad circulating.

but also could bring it back to a pump issue of not circulating.

shut that hot rad and see if you can get the other one hot, if that gets hot then open the other again.

if one then gos cold again i would look at the pump issue.

is the pump on max speed ?

 

[fakinsupa]

its poss it could be a pump but i don't think so.
balancing not an issue at the moment. not with only two rads open.
the boiler will cycle like that at the moment with only one rad circulating.
as the water is not really dropping in temp on one rad circulating.

but also could bring it back to a pump issue of not circulating.

shut that hot rad and see if you can get the other one hot, if that gets hot then open the other again.

if one then gos cold again i would look at the pump issue.

is the pump on max speed ?

Thank you very much for your help. I waited till the one rad was hot then turned the other downstairs rads on. They also got hot and they all stayed hot. I then turned the system of and have tried again turning the downstairs rads on from cold. Heate stayed on for about 1min and cut of. after about 2 hours one rad hot the others only warm (just warm)

Any further ideas?

Could it just be air inthe system? Our system has always had a lot of air in it. Where would the air come from and how do you get it all out?