Baffled by central heating with a mind of its own......ready to give up!!

[Ermintrude]

Leave sludge remover for a week and use heavily

 

[JoseGaf]

Leave sludge remover for a week and use heavily

Ta, any recommendations on what sludge remover to use please?

 

[kay-jay]

Ta, any recommendations on what sludge remover to use please?

Fernox or sentinel or magnaclean brand. Dont buy the cheap stuff.

 

[solutions]

Fernox or sentinel or magnaclean brand. Dont buy the cheap stuff.

Why what is the difference?

 

[kay-jay]

Peace of mind [emoji3]

 

[JoseGaf]

Fernox or sentinel or magnaclean brand. Dont buy the cheap stuff.

Thanks for the advice....with get some ordered

Have now cleaned out 3 rads and a towel rail and haven't turned the heating on at all...just used hot water......all the cleaned rads are closed off at feed and returns......however the boiler pressure is slowly dropping (over a course of hours).....I keep topping up the system to make sure we have hot water......I've only had the downstairs rads off and there are no leaks.....there are no noticeable wet patches up above in the ceiling so I'm wondering where the water is going thats causing the pressure drop.....any ideas??

 

[jtsplumbing]

Did you refill the radiators ? if not valves possibly letting by into radiator

 

[JoseGaf]

Did you refill the radiators ? if not valves possibly letting by into radiator

Cheers....refilled rads and pressure leak seems to be sorted

 

[JoseGaf]

Right, all downstairs radiators have been removed and cleaned out, system drained then 1 litre of x400 sentinel added. Boiler then started up, rad returns opened one by one and bled after each got hot....managed to get heat in all of them for the first time....however once all rads opened 2 of the 3 original problem rads reduced their heat to warm at best....i imagine this is either down to the poor pipe set up meaning 6 rads is probably the max the system can take or the sludge remover just needs more time to run.....hope its the latter

 

[goz666]

How far are you opening the lockshield valves, if I was you I would turn each one off and then open up by one turn and no more. You may find that's too much so try half turn. On a lot of systems balancing is probably the most difficult job there is. Any rads with no TRV, close one side down and reopen one turn.

 

[tamz]

Move the L/s 's in ¼ turns when balancing

 

[diamondgas]

6 days and still little progress JoseGaf .... You have patience

I've found pipes blocked with stones, rubber washers and even loft insulation as well as sludge!! It's a process of elimination when diagnosing where the origin of the fault lies. Radiators aren't the cause, poor heat to them is the result of restricted flow to them. Experience and understanding in boiler and system design is important when diagnosing and resolving your issue I'd say. Chemicals aren't always the solution to poor flow, sometimes you just have to delve deeper.

Could you sketch out your heating layout, pipe sizes to radiators etc? Maybe then better advice can be given? Did you clean out the filter, by-the-way?

 

[Millsy 82]

Right, all downstairs radiators have been removed and cleaned out, system drained then 1 litre of x400 sentinel added. Boiler then started up, rad returns opened one by one and bled after each got hot....managed to get heat in all of them for the first time....however once all rads opened 2 of the 3 original problem rads reduced their heat to warm at best....i imagine this is either down to the poor pipe set up meaning 6 rads is probably the max the system can take or the sludge remover just needs more time to run.....hope its the latter

You are spending all this time and money trying to repair a bodge (6 rads off 15mm pipe will struggle at best) why not just bite the bullet and repipe the system? Is your time worth so little that you are willing to spend most of your free time trying to sort this when a decent installer will sort it within a couple of days max (I would of thought not seeing the house makes it quite difficult to say for certain)

 

[JoseGaf]

You are spending all this time and money trying to repair a bodge (6 rads off 15mm pipe will struggle at best) why not just bite the bullet and repipe the system? Is your time worth so little that you are willing to spend most of your free time trying to sort this when a decent installer will sort it within a couple of days max (I would of thought not seeing the house makes it quite difficult to say for certain)

I've done a bit of research and messaging on this forum plus I've spent £8 on sentinel sludge remover off ebay and £60 on a couple of oil heaters......other than that 3 hours approx to clean out the downstairs rads.....I appreciate it all needs re-piping and probably a new boiler but I just cannot afford it right now, I don't have £3-4k.....I'm pretty pleased with the results I've had thus far thanks to good advice from guys on this thread.....I have heating again which comes on everytime the boiler fires and I have heat in rads that have never had heat in 4 years. Its not a big house and am sure restricting the flows via the returns along with the cleaning and sentinel have helped a lot.
Next steps are to get the upstairs rads off and cleaned over the next few weeks, drain the system then stick some more sentinel in.

 

[JoseGaf]

6 days and still little progress JoseGaf .... You have patience

I've found pipes blocked with stones, rubber washers and even loft insulation as well as sludge!! It's a process of elimination when diagnosing where the origin of the fault lies. Radiators aren't the cause, poor heat to them is the result of restricted flow to them. Experience and understanding in boiler and system design is important when diagnosing and resolving your issue I'd say. Chemicals aren't always the solution to poor flow, sometimes you just have to delve deeper.

Could you sketch out your heating layout, pipe sizes to radiators etc? Maybe then better advice can be given? Did you clean out the filter, by-the-way?

Hi, I've not cleaned any filters as I'm not sure of what I'm doing. I have found the user manual for my boiler (heatline viso) on line which has all the parts identified but not sure what needs cleaning....any advice most welcome....I'll have a go at sketching the system

 

[diamondgas]

Hi, I've not cleaned any filters as I'm not sure of what I'm doing. I have found the user manual for my boiler (heatline viso) on line which has all the parts identified but not sure what needs cleaning....any advice most welcome....I'll have a go at sketching the system

"Not sure of what you're doing" ... Get someone in who is, regards this filter, JoseGaf! It may well be where the problem lies and in my opinion needs eliminating before you remove radiators and rip up floorboards.

 

[JoseGaf]

"Not sure of what you're doing" ... Get someone in who is, regards this filter, JoseGaf! It may well be where the problem lies and in my opinion needs eliminating before you remove radiators and rip up floorboards.

when I say I don't know what I'm doing....I'm not a plumber or central heating engineer but have a mechanical engineeing degree and a reasonable appreciation of flow mechanics and electronics....I just don't know the ins and outs of boilers, thats why I've asked for help on here which has been really really useful........I've had 3 different central heating engineers round and not one has ever mentioned a filter (the guys who've come are able to change things but haven't been able to diagnose route cause)....I've downloaded the boiler manual and the description of how to clean the filter is pretty non-descript unfortunatley...I understand it is located near the heating return to the boiler but from memory it sits behind the pump so I imagine I either have to remove the pump or approach from underneath....if this is a job I'm not totally happy to undertake I just won't do it

 

[Millsy 82]

but have a mechanical engineeing degree and a reasonable appreciation of flow mechanics and electronics

Explain this please. If you have a pump trying to pump water around a heating system what will affect it? The more resistance that is on that circuit will prevent it from flowing correctly? So if your 6mtr head pump (as on most combis) is trying to circulate around an inadequately sized system it will dramatically reduce the effectiveness of the pump. If you put a new pump on a pristine system it may work for a while but not for long.

From what your posts have been saying I have read that this is an ongoing problem that you have been trying to sort through 3 different engineers? (I assume these have all been paid for what they have done) and you have been trying things to sort in the past? So I think you probably have spent longer and more trying to sort this problem than you say?

By all means keep flushing the system it's not going to do any harm but eventually you will end up having the pipework replaced.

If you can't afford 3-4k for a new boiler and heating system then don't have a new boiler and radiators just have the pipework redone then have the boiler and radiators replaced at a later date.

 

[Millsy 82]

As an example. I went out to a bungalow that had a whole new heating system installed 6 months earlier, it was a 5/6 rad system, all the rads took an age to heat up and some only worked every now and then, a quick look around and all the rads were shut off only allowing a very low flow through them, I opened a few up and water shot round them but the others wouldn't work at all, popped my head up in the loft and found that as soon as the flow and return entered the loft it was reduced to 15mm speed fit. I shot of and picked up a few 22 fittings and 2 6mtr lengths of speed fit and upgraded the flow and return, I filled up and turned the boiler on all the rads got red hot in 5-10 mins instead of getting Luke warm in 35-40 mins.

 

[JoseGaf]

As an example. I went out to a bungalow that had a whole new heating system installed 6 months earlier, it was a 5/6 rad system, all the rads took an age to heat up and some only worked every now and then, a quick look around and all the rads were shut off only allowing a very low flow through them, I opened a few up and water shot round them but the others wouldn't work at all, popped my head up in the loft and found that as soon as the flow and return entered the loft it was reduced to 15mm speed fit. I shot of and picked up a few 22 fittings and 2 6mtr lengths of speed fit and upgraded the flow and return, I filled up and turned the boiler on all the rads got red hot in 5-10 mins instead of getting Luke warm in 35-40 mins.

you are right, the system is rubbish and so is the boiler but its what I've got. In the last 4 years I have honestly spent less than £300 and that includes a new diverter valve which I fitted.....I do pay £15 a month for Eon boiler cover which arguably I'd still have if I had a new boiler.
The concept of knocking out my kitchen wall, a hole in my dining room wall and pulling up floorboards in all 3 bedrooms scares me....I have a 10mth old and a 2 1/2 yr old, the upheaval and having to re-decorate/plaster is something I just can't do at the moment....let alone probably afford.
There have been issues with the heating in the past but its now already better than its ever been....I'm waiting for my 'mates rate' engineer to fit me in as I want him to fit 22mm out of the boiler and as far as he can plus remove the unnecessary rad in the bathroom (closest to the boiler as theres already a towel rail in tandem)....these will both help.....

 

[diamondgas]

........I've had 3 different central heating engineers round and not one has ever mentioned a filter (the guys who've come are able to change things but haven't been able to diagnose route cause)....I've downloaded the boiler manual and the description of how to clean the filter is pretty non-descript unfortunatley...

I once re-charged a vizio and blocked the filter. They're quite easy to access and are eternal to the boiler, as I believe I mentioned before? Remind me/us please; is your heating system one pipe or two? And is it all in 15mm? I've seen a lot more than 6 rads ran of 15mm and heat no bother, by-the-way! You describe a primary restriction, by sounds of it if the temp diff between F&R are extreme?