What could be wrong with central heating?

[kev1985]

Hoping for some advice as I seem to be hitting a brick wall.

Moved into a house last year, radiators down strairs (4 of them) never really got warm, replaced the combi boiler this year as it was loud and leaking (its in the loft which has been converted into a room).

Since turning the heating on none of the radiators down strairs get hot at all, the flow to the rad gets hot but the heat doesnt get into the radiator then the pipe goes cold. Up stairs one radiator used to get really warm, we moved it to another wall in the room now it doesnt get hot either.

Only 4 rads get hot, one in the loft, 1 in each toilet and 1 in our babies room.

Had 3 plumber out to have a look:

1 - Said it needed balancing, done that and left, the problem wasnt fixed
2 - Said it was a crossed pipe and pulled up the floor in the loft, realised there wasn't a hatch and left
3 - Said we need a power flush and will give us a quote

I've paid £450 on 3 plumbers and none of them have resolved the issue. What could it be and how can it be fixed? Would I need the whole house re-piped.

House in 1990's built, detached.

Any help or suggestion would be appreciated.

 

[Chuck]

We'll need a bit more information from you. Let's start with:

(a) what make and model of boiler do you have?
(b) do you have thermostatic valves on the radiators?
(c) do you have motorised 'zone valves' controlling which floors/parts of the house receive heat?
(d) is it a sealed (pressurised) system or do you have a small feed/expansion tank in the roof?
(e) Was the system flushed properly when the combi was replaced?
(f) Did the guy who recommended a 'power flush' do any tests / checks before coming to that conclusion?
(g) How does the boiler behave when the system is running?

 

[kev1985]

We'll need a bit more information from you. Let's start with:

(a) what make and model of boiler do you have?
(b) do you have thermostatic valves on the radiators?
(c) do you have motorised 'zone valves' controlling which floors/parts of the house receive heat?
(d) is it a sealed (pressurised) system or do you have a small feed/expansion tank in the roof?
(e) Was the system flushed properly when the combi was replaced?
(f) Did the guy who recommended a 'power flush' do any tests / checks before coming to that conclusion?
(g) How does the boiler behave when the system is running?

Thanks Chuck.

A - its a Baxi 830HE Combi - installed July this year
B - Yes all but one has a thermostatic valve
C - No, there are no motorised zone valves
D - Its a pressurised system
E - I was told a system clean with sludge remover would happen when the boiler was installed, not sure if it happened, the raditators werent taken off the wall so maybe a solution run through the pipework but I know a magnaclean filer was put on
F - The power flush recommendation was because the rads are on the ground floor and thats where most of the issue is, the magnaclean filter was put on in July, the installed changed in early Sept, didnt tell me why he just done it and charged me. the power flush guy took the filter off and showed me that is was quite full, it had only been on 2 weeks since it was replaced and the heating hasn't been on much
G - The boiler sounds okay when its running, hot water is there when needed too. The boiler does make a flushing noise for a few minutes every couple of night about 4 in the morning.

I've tried turning the thermostaic valves off on the rads which are getting heat, it has make the others that done heat up a tiny, tiny lit better, I mean it its only very slightly warm across the top grill and nothing else.

 

[Deleted member 120897]

Why haven’t you had the installer back? It should be their problem to rectify without it costing you. Imo, it’s still not balanced.

 

[Chuck]

Part of the commission process for a boiler installation is to get the system running and demonstrate it working to the customer and explain the controls. Did that happen? Did the installer provide you with the completed checklist?

In your position, I'd limit myself to the following:

(a) go round and bleed the radiators,
(b) check the boiler's user instructions to make sure it's not been left in some type of 'summer mode', and the flow temperature is set to something reasonable, e.g. 60°C and follow any instructions for the home owner re faults and 'resetting' the boiler.
(c) get the installer back.

The system is sealed and should have been properly flushed by the installer as part of the installation/commissioning so a 'powerflush' should not be necessary. If they don't cooperate contact Baxi customer support and get them to send an approved engineer to check the boiler and installation. If there's anything wrong with the boiler they'll fix it. If there's a problem with the rest of the system they'll tell you what it is and you can decide where to go from there.

 

[jh2254]

Have you sorted out your problem ? Have a look at my similar thread.

Problems with small bore pipe and an old central heating system

Use your magnet to investigate extent of blockage, depending on what you find- cut out and replace that section of pipe

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