About 1.5 bar I think, it goes up to higher green zone when running
Central Heating Nightmare - Air in System Daily
- Thread starter Cellophaneskies
- Start date
So, almost a month later and no improvement?, think you will have to be more proactive, I would drain it all down, flush it a few times, install the Spirovent, fill it up with no inhibitor, see if the air stops venting after a reasonable period of say a week or so, max, then re introduce the inhibitor gradually.
Still puzzled.
What's your main problem, the air build-up, or that the house isn't warmed adequately? For the latter, possibly the pump is clogged up with muck, and it might be worth checking. No need to disturb the pipework, just remove the head - 4 Allen-head setbolts.
I don’t think so, not that I’ve noticed..
Issue is that one or two rads will have really poor performance - lukewarm to touch - bottoms of some rads lukewarm - can hold hand on them. Plus lots of gurgles, clicks, whooshing noises which do my head in and stop me using certain rads as they wake me up!
Performance varies. Sometimes it’s pretty good, but when I do my ritual of bleeding I’m reminded at how good the performance can be. It’s ’ok It’s warm enkugh’ vs ‘I’m going to die unless I open some windows’. Basically meaning most of the time I’m paying a lot of money to heat very slowly.
Did you get round to trying to light it?
Make sure someone is videoing just in case its worth it?
Unsure, perhaps getting caught somewhere, or some sort of reaction started in the system that generates a gas?
I did once and not much success but I’ll try again when we’re using the system again..
Yes standard sized house, upstairs rads are about 1.5m above the boiler but difference distences away.
I haven’t updated this post as I haven’t been using it so much and was so annoyed with it. Had a power flush of the system, no difference. Some dads had their thermostats and lock shields the wrong way around, ie flow return. I’ve swapped those around to see if that helps. Then been advised to take thermostats off and see if the issue continues..
Running out of avenues here. Costing more to hunt the issue down than near the noose and run it at lukewarm temps! Will update.. I need a rad replaced and I’ll try and try that in with replacement of the last bit of original pipe work that comes out the boiler, hoping it won’t be an astronomical cost..
Running out of avenues here. Costing more to hunt the issue down than near the noose and run it at lukewarm temps! Will update.. I need a rad replaced and I’ll try and try that in with replacement of the last bit of original pipe work that comes out the boiler, hoping it won’t be an astronomical cost..
Hello everyone. Time for my yearly fight with my heating system! It's exciting! It's unpredictable! It's a rollercoaster of emotions!
I'll reiterate so that no one has to read through all these old messages.
ISSUE
Sealed combi boiler central heating system with 8 rads will run lukewarm if not touched. Heating may run for hours but the house never feels hot or fully heated and you need a jumper. Rads 'hot' at top but the bottom is cold or lukewarm. Worse at the end of the run (diagram in old post). also lots of gurgling, slurping, trickling noises especially when first turned on.
WORKAROUND
Last couple of years I've found that I can bleed the system almost daily and get more air out. If I do this when the system runs, it will fizz and spit as if air is in the water. For a while I turned off rads in succession and did this bleeding process, with the highest point getting the best resuls. After this the heating would get insanely hot, tropical, I'd need to take clothes off.
This year I've bought smart thermostats to try and simplify this process and I've found that if i turn off all rads except the last two in the chain, and let them run for 10-15 minutes from cold, I can the turn on the rest of the rads in turn and I'll get what feels like full performance from the system. house will be tropical in 30 minutes, compared to only lukewarm after an hour or two if I don't touch anything.
TROUBLESHOOTING
I've tried..
New boiler (5 or 6 years old now)
All new, and bigger rads, except one which I suspect is about 15 years old. Mostly Stelrad branded
Taken each rad off and flushed with hose
Had all the pipework replaced, and uprated to thicker, apart from two drops - the drop that comes from the boiler to the rest of the system and the drop to the last rad in the chain. Suspect original job was DIY.
Various balancing techniques
Tried isolating various rads to see if system is ok without a certain one in the chain - no difference
Added X400, X800 (different times) and drained as a treatment process
Most Recently..
Powerflush by heating company (grubby but not excessive)
Made sure the lockshield and thermostatic valve are the correct side of the rads, on supply and return
SUSPICION
It's almost as if there is an 'air lock' or some sort of block that exists until I leave only two rads on and 'force' that airlock through. I always always have slurping, trickling, ticking which drives me insane, suggesting there's air in there. this will be worst on the rads that are usually the worst the last in the chain. If I turn off all upstairs rads, the downstairs will make these noises.
Or there is corrosion in the oldest pipework that's generating some sort of gas..
OBSERVATIONS
No leaks, pressure doesn't drop or raise (unless I bleed or use the filling loop)
Magnaclean pulls some crud out but not excessive
There is inhibitor in the system, no difference between brands
NEXT STEPS
All I can think of to do is-
Get a deaerator fitted to see if this reduces air noises etc
Replacing the remaining pipework - about 2m drop at end, 2m drop that comes from the boiler
Exorcist or atom bomb
Does anyone have any ideas or advice. At least right now I can use the smart thermos to coax the heating to work but it's still inconvenient, I can't ever forget about it, and it's really noisy!
I'll reiterate so that no one has to read through all these old messages.
ISSUE
Sealed combi boiler central heating system with 8 rads will run lukewarm if not touched. Heating may run for hours but the house never feels hot or fully heated and you need a jumper. Rads 'hot' at top but the bottom is cold or lukewarm. Worse at the end of the run (diagram in old post). also lots of gurgling, slurping, trickling noises especially when first turned on.
WORKAROUND
Last couple of years I've found that I can bleed the system almost daily and get more air out. If I do this when the system runs, it will fizz and spit as if air is in the water. For a while I turned off rads in succession and did this bleeding process, with the highest point getting the best resuls. After this the heating would get insanely hot, tropical, I'd need to take clothes off.
This year I've bought smart thermostats to try and simplify this process and I've found that if i turn off all rads except the last two in the chain, and let them run for 10-15 minutes from cold, I can the turn on the rest of the rads in turn and I'll get what feels like full performance from the system. house will be tropical in 30 minutes, compared to only lukewarm after an hour or two if I don't touch anything.
TROUBLESHOOTING
I've tried..
New boiler (5 or 6 years old now)
All new, and bigger rads, except one which I suspect is about 15 years old. Mostly Stelrad branded
Taken each rad off and flushed with hose
Had all the pipework replaced, and uprated to thicker, apart from two drops - the drop that comes from the boiler to the rest of the system and the drop to the last rad in the chain. Suspect original job was DIY.
Various balancing techniques
Tried isolating various rads to see if system is ok without a certain one in the chain - no difference
Added X400, X800 (different times) and drained as a treatment process
Most Recently..
Powerflush by heating company (grubby but not excessive)
Made sure the lockshield and thermostatic valve are the correct side of the rads, on supply and return
SUSPICION
It's almost as if there is an 'air lock' or some sort of block that exists until I leave only two rads on and 'force' that airlock through. I always always have slurping, trickling, ticking which drives me insane, suggesting there's air in there. this will be worst on the rads that are usually the worst the last in the chain. If I turn off all upstairs rads, the downstairs will make these noises.
Or there is corrosion in the oldest pipework that's generating some sort of gas..
OBSERVATIONS
No leaks, pressure doesn't drop or raise (unless I bleed or use the filling loop)
Magnaclean pulls some crud out but not excessive
There is inhibitor in the system, no difference between brands
NEXT STEPS
All I can think of to do is-
Get a deaerator fitted to see if this reduces air noises etc
Replacing the remaining pipework - about 2m drop at end, 2m drop that comes from the boiler
Exorcist or atom bomb
Does anyone have any ideas or advice. At least right now I can use the smart thermos to coax the heating to work but it's still inconvenient, I can't ever forget about it, and it's really noisy!
Thanks. Trades all seem surprised by this suggestion and often discourage it but I’m going to find someone that will just do what I ask. Do you have any advice on brand at all..?
A light bulb went on when you mentioned possible DIY install, what's the betting it's a combi conversion, and Mr DIYer has got the pipework wrong under the floor, so that for example the flow is going down what was the old cylinder return, or something similar?
This happened to me when apprentice altered pipework in airing cupboard, despite me labelling pipes and tell him to connect pipe A to pipe B, and cap off pipe C. It worked, but badly, and displayed exactly the symptoms you have.
This happened to me when apprentice altered pipework in airing cupboard, despite me labelling pipes and tell him to connect pipe A to pipe B, and cap off pipe C. It worked, but badly, and displayed exactly the symptoms you have.
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