Clearly manifolds were too expensive for whover put this system in, they branch of the 15mm pipe with tees!
Is my plumbers advice correct- Faulty Central Heating System
- Thread starter mike.braund
- Start date
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I would suggest that powerflushing would be a waste of effort as all your rads are new! If would clean the boiler, but that doesn't appear to be a particular problem.
Have you tried turning off all rads bar one at a time to be sure you're rid of air locks?
Does each rad work if you do that?
If they do then you could "simply" have a big balancing problem, which could take a bit of resolving, with various lengths of microbore to each rad. Start with all the rads open just a tiny bit (1/4 turn say) and there should be enough pump pressure to get some flow to them all. Then open the furthest another 1/4 turn, and so on.
Putting a combi in will do nothing to help with any blockage or other circulation problem you have. That would still need to be solved. They come with a 6m pump instead of the 5m you probably have, but 6m pumps are cheaper than combis!
If you have a circuit or two not passing any water, then a powerflusher wouldn't get any chems down it either. You could try being brave and try the mains to blast it out (both directions). That's what I'd do, taking steps to make sure the pressure didn't get too high. Adding a flull size drain point or two at key points would make life easier.
Have you tried turning off all rads bar one at a time to be sure you're rid of air locks?
Does each rad work if you do that?
If they do then you could "simply" have a big balancing problem, which could take a bit of resolving, with various lengths of microbore to each rad. Start with all the rads open just a tiny bit (1/4 turn say) and there should be enough pump pressure to get some flow to them all. Then open the furthest another 1/4 turn, and so on.
Putting a combi in will do nothing to help with any blockage or other circulation problem you have. That would still need to be solved. They come with a 6m pump instead of the 5m you probably have, but 6m pumps are cheaper than combis!
If you have a circuit or two not passing any water, then a powerflusher wouldn't get any chems down it either. You could try being brave and try the mains to blast it out (both directions). That's what I'd do, taking steps to make sure the pressure didn't get too high. Adding a flull size drain point or two at key points would make life easier.
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C
compheat
Putting a Baxi combi in wouldn't improve the flow through the pipe work and has already been said the existing boiler is cutting out because the heat is not getting away. The fact you cant vent the rads when the heating is off also tells you some things not right, Isn't the 105E a standard efficency combi and not a condenser. For £2000 i would be putting in a Worcester 28i Green star and flushing the system.
Thanks for all the help so far guys.
Chrishutt was of course quite correct in saying that fitting a gate valve was a waste of time, but having drained down to check the anti gravity valve, I thought I might as well put one in.
No improvement so far then, a couple of tubs of X400 are going in tomorrow, I will leave it for a week or two and see what happens.
As each rad is capable of getting hot if it is the only one switched on, it seems to me to rule out a microbore blockage. Is there any possibility that one of the larger bore pipes is partially blocked, only letting through enough water to heat one or two rads ?
Another theory: Is it possible that the heat exchanger in the boiler has a partial blockage on the return side of the CH?
If so can they be stripped down?
Chrishutt was of course quite correct in saying that fitting a gate valve was a waste of time, but having drained down to check the anti gravity valve, I thought I might as well put one in.
No improvement so far then, a couple of tubs of X400 are going in tomorrow, I will leave it for a week or two and see what happens.
As each rad is capable of getting hot if it is the only one switched on, it seems to me to rule out a microbore blockage. Is there any possibility that one of the larger bore pipes is partially blocked, only letting through enough water to heat one or two rads ?
Another theory: Is it possible that the heat exchanger in the boiler has a partial blockage on the return side of the CH?
If so can they be stripped down?
PS
Told the plumbersw to forget the combi.
Told the plumbersw to forget the combi.
I'd be thinking along the same lines. It's a long time since I last installed an Ideal Concorde, but I seem to remember that the heating (pumped) return connection was to a special spreader (?) tube inserted into the tapping on the boiler to stop the pumped water disturbing the stratification in the boiler.
Anyway, it might be that this tube or its outlets are clogged up, so if it doesn't clear with chemicals and flushing, you could try unscrewing it, although I think you may only be able to do this from the back. It might be easier to open a plugged tapping on the front to try to clear out debris, but definitely a last resort.
I have only read the first few posts on this thread so am posting blind.
I suggest a gate valve in HW zone will not make any difference. During summer, Gravity HW heats up in good time. During winter, it takes longer because the pump 'disrupts HW convection'.
The pump chucks the water round the rads NOT through the 28mm to the cylinder (in this case).
What I would be doing is take temperature readings at various points along the flow and return and make sense of it. What about the two port valve. Is it opening? Not the first system I have been to where the two port valve microswtich is not used. In such a system, the boiler and pump would run but shut motorised valve would have a similar effect if the gravity zone was causing secondary flow through nearby rads.
Obviously what I have said above might be a load of bull poop. Only way forward is to diagnose the defect and not have a conference based on loose ideas and then put them into force (like replace the pump- what has that achieved- sum total of ZERO)
I suggest a gate valve in HW zone will not make any difference. During summer, Gravity HW heats up in good time. During winter, it takes longer because the pump 'disrupts HW convection'.
The pump chucks the water round the rads NOT through the 28mm to the cylinder (in this case).
What I would be doing is take temperature readings at various points along the flow and return and make sense of it. What about the two port valve. Is it opening? Not the first system I have been to where the two port valve microswtich is not used. In such a system, the boiler and pump would run but shut motorised valve would have a similar effect if the gravity zone was causing secondary flow through nearby rads.
Obviously what I have said above might be a load of bull poop. Only way forward is to diagnose the defect and not have a conference based on loose ideas and then put them into force (like replace the pump- what has that achieved- sum total of ZERO)
Don't bother with it. Too gentle, takes weeks to do any good and won't dissolve hard stuff, which probably lurks in your boiler.
The "distributor tube" may well have had it as ChrisH says.
I think I'd just shove the mains up the return (via pump valve) to flush out what I could from the boiler and hope for the best. Doesn't sound like there's a problem in the pipes to the rads. If that were true some would be much clearer than others.
chrishutt said:I seem to remember that the heating (pumped) return connection was to a special spreader (?) tube inserted into the tapping on the boiler to stop the pumped water disturbing the stratification in the boiler.
Absolutely.and it was supposed to be in a particular orientation-indicated by a mark on the outside of the hex. it was fitted into
An update on this topic, first posted 9 months ago.
As mentioned in one of my posts, the x400 was put into the system.
Weather got warmer, forgot about the problems over the summer, and have been too busy to revisit the problem.
But a couple of weeks ago, hey presto, the heating works, which came as a total surprise!
So big thanks to everyone who helped with this problem, and to X400!
Must remember to drain down & put some inhibitor in.....
As mentioned in one of my posts, the x400 was put into the system.
Weather got warmer, forgot about the problems over the summer, and have been too busy to revisit the problem.
But a couple of weeks ago, hey presto, the heating works, which came as a total surprise!
So big thanks to everyone who helped with this problem, and to X400!
Must remember to drain down & put some inhibitor in.....
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Crickey!!! 9 months ago....!!!! I would think that the X400 will have eaten everything (including your Heat Exchanger) by now
Drain it ASAP. Make sure you add Inhibitor and Good Luck!
Drain it ASAP. Make sure you add Inhibitor and Good Luck!
So much for a rare day off at the weekend!
Thanks guys, I will do it Saturday.
Thanks guys, I will do it Saturday.
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