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Desperately looking for help, as SSE home services seem clueless.
We have a pressurised system using an old but reliable Ideal classic boiler.
Every now and then, I have to top up the pressure in a little red bottle in a downstairs cupboard.
However, for a while now, the fill loop doesn't seem to have been working.
I no longer feel water rushing into the red bottle, and I no longer see the pressure gauge going up.
Since these fill-loop problems, the central heating has been problematic.
Basically, the boiler and pump will keep going even through the controls say they should be off.
SSE home services have replaced the pump, a solenoid valve in the boiler and they attached a foot-pump device to a little bicycle-tyre style valve on the red bottle.
None of these seem to have stopped the problem, the boiler and pump were still running yesterday PM when they should have been off.
HELP PLEASE!!!
 
The red bottle you talk off is the expansion vessel .what they have tried to do is repressurise it to try and solve the problem you've been having (losing water pressure). All this aside let's get down to the actual problem.
You've said you've been doing this for awhile, seeing that your system is old the first thing I would try is ;
Take a pz1 screwdriver and remove the black taps from the valve (s) try using an adjustable wrench or pliers to turn the spindle which operates the valve.
With frequent use this plastic taps wear and stop turning the valve, even when you think it is .
The red vessel may also have failed .
How often are / was you repressurising the syste
 
Thanks for the reply.
When the fill loop worked, I was maybe having to top it up once or twice a month.
The thing is, I was never sure what figure it should have been showing on the gauge, or whether I should have been topping up hot or cold.
I used to keep the guage somewhere around the 1.5 to 2 bar level once was running.
Any less than that and I noticed I was having to bleed radiators from time to time.
Keeping it at that sort of pressure used to keep the bleeding away and gave us good heat and shower power.
I'm not really confident enough to muck about with the fill loop, just in case water starts going everywhere.
 
When the system is cold the pressure should be set between 1-1.5 bar. Air trapped in your system is down to it being introduced everytime you repressurize not the pressure level itself.
IF you're having to continually fill up the EV (red thing) you have a leak, simple as. Get them back in tell them what you told us.
 
Basically, I need to know what angle I should 'attack' SSE home services from.
I'm just amazed they've never noticed the fill loop issue themselves, it's not exactly encouraging.
 
Losing pressure = leak
Having to top up = leak
Keep pressure above 1bar when cold, try not to refill when hot.
 
Okay so check the tundish for signs on leaking, if this is dry and doesn't look like it's been leaking from any expansion / TnP relief valves .If no signs of leakage is present I would imagine youve got a leak somewhere .I would expect on a new system a few times in the first 6mts. Then maybe twice annually or when bleeding radiators or doing work.

The most common situation for this is that the expansion vessel has failed . When you first fire up the ch from cold, keep an eye on the pressure for 15 minutes and see if you can see a great rise (over 1 bar) if it rises more than a bar .Replace the expansion vessel .

Twice monthly seems to unfrequent for an expansion vessel fault and I'd say definitely points towards a small leak on the system.

Cold system pressure should be between 1-1.5bar .
 
How do you go about tracing a leak in a pressurised system?
We have a few TRVs on radiators that ooze drops of black gunge onto the floor every now and then, would that be enough to reduce pressure?
I'm terrified of the word leak as it conjures up images of floorboards being ripped up etc.
 
Yep small drips will depressurise the system.

Seems they also left the foot pump they used to inflate the EV on the system. If the pump has a pressure indicator leave it and take a reading when cold, it shouldn't be below 1bar.
 
No they didn't leave the foot pump, sorry if I gave that impression.
So, really, I should point out the various leaky TRVs we have as well then.
I've never bothered as I don't see them as a big issue.
They only tend to drip black gunge when the heating's been off for an extended period.
 
If you have black gunge leaking out of the valves your system is in a worse condition than you think, had no inhibitor in system for years.
 
I don't doubt the system could do with a flush, but the money that entails is something we just don't have....
 
Did they dump the system pressure to check the expansion vessel pressure? Half a cup of water can drop pressure.
Between 1.0 and 1.5 cold and about 1.5 to 2.0 when running hot, but depends on system size.
Does it ever get up to 3 when running?
 
With all the new stuff they've given me over the past few weeks, I'm probably quids in.
I've had a new pump, new controls and a new 'something' in the boiler.
I keep thinking they're chasing their tails and missing the real problem, which is a lack of pressure.
I'm correct in thinking a lack of pressure would make the boiler and pump 'run on' after the controls have gone off?
The pump is really loud when this happens, which suggests a lack of water.
Once the heating 'officially' comes back on via the controls, the pump gets progressively quieter.
 
You need to get them back in, the boiler should not be firing if the controls are off that just sounds bizarre. Pump can run on when the boiler isn't firing certainly but the lack of water you describe sounds like an airlock. When the system is pressurised you should be able to bleed it out.
 
I think the boiler (and pump) running on were why they fitted new controls.
They obviously blamed a control panel problem.
But I'm not convinced, I think it's all to do with lack of pressure in the system due to the fill-loop not working etc.
They're visiting tomorrow.
 
If you have any motorised valves (zone valves that will have a square plastic or metal head) then they can fail and put power to boiler and pump.
But I would be astounded if the boiler service blokes didn’t check that.
Your TRVs leaking when heating off means they are always leaking and this will contribute to system water pressure loss
 
EV air pressure can only be set once you have got rid of the system water pressure, air pressure should be around 0.9 bar, if water leaks from the schroeder valve then the EV needs replacing.
 
EV air pressure can only be set once you have got rid of the system water pressure, air pressure should be around 0.9 bar, if water leaks from the schroeder valve then the EV needs replacing.

I've no idea what this means.
But there's no visible water leaks from the red bottle.
 
I've no idea what this means.
But there's no visible water leaks from the red bottle.

It means the air charge to the red expansion vessel can only be set if the system water pressure is put down to zero.
The reason the air charge has to be kept to a certain pressure is so that the vessel allows system water to expand without over pressurising and resulting in the pressure relief valve opening and discharging some system water
 
Remove the dust cap from the EV's air valve, press the needle down, you should only get air released, if you get water the EV (red bottle) is no good.

Although you sometimes will get some water inside vessels air side
 
So, bottom line, do you think the 'broken' fill loop and running-on of the boiler and pump are unconnected?
Just coincidence?
 
You have two problems...system pressure and run-on they are it appears unconnected.

Pressure - leaking TRV's/EV, dodgy filling loop.
Run on after complete switch off (your description) - Faulty controller/ PCB, valves, very odd.
 
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When I say complete switch off, I mean the timer controls.
They're both showing off, but the pump and boiler keeps going.
The pump gets progressively louder the longer it runs on, which I assume is because no water is going through it (the radiators do cool down)
If I press 'advance' and make the heating controls light up again, the pump goes back to being quiet after a while.
So it would suggest the pump is running on, but some valve or other is closing off water to it.
When I press 'advance' this valve is opening again and allowing water to go through the pump again.
 
Wait for your engineer to turn up, get them to sort out the pressure/filling loop and point out the leaking TRV's. We can't accurately diagnose your run on issue remotely but as Best mentioned motorised valves can fail and energise your boiler and pump, get them to check that too.
 
I have come across the boiler & pump running on a few times due to a 2 port valve actuator fault, valve closes but microswitch still in open position, water will then circulate through the bypass.
 
Engineer came, unfortunately I couldn't be there in person but I spoke to him on the phone. He asked if I knew where some valves were, my wife advises he then 'changed some bits under the floor'. I also noticed he changed the fill loop pipe/valves. Fingers crossed the running on stops. Next move is to get them to change the 3 x leaky TRVS.
baby steps!
 
The red bottle you talk off is the expansion vessel .what they have tried to do is repressurise it to try and solve the problem you've been having (losing water pressure). All this aside let's get down to the actual problem.
You've said you've been doing this for awhile, seeing that your system is old the first thing I would try is ;
Take a pz1 screwdriver and remove the black taps from the valve (s) try using an adjustable wrench or pliers to turn the spindle which operates the valve.
With frequent use this plastic taps wear and stop turning the valve, even when you think it is .
The red vessel may also have failed .
How often are / was you repressurising the syste


I was thinking the exact same i thought SSE would have picked that up On the levers though!!
 
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