Agile";p="1239177 said:
Baxi 105e instant combi boiler - problem.
- Thread starter Ulley Ranger
- Start date
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Hi Tony,
That's why I posted here. I wasn't trying to impose my inexpert view, I was postulating what has been bugging me hoping that some explanations would be forthcoming. Like why after two years would an extra expansion vessel help? Have I understood correctly that the 105 HE expansion vessel has a dual role?
I read on another forum to press the plunger in the valve and see if water, air or nothing came out but that was after the fact and the boiler had been removed.
I may have panicked a bit into the new boiler since my wife is convalescing after a major operation and a good supply of hot water is essential. The BAXI which has never missed a service, had been up and down in truth for a few months but when the DHW failed completely and the RED light came on for pump failure (which it was not) or loss of pressure I knew it was the latter and the gauge confirmed it. A recharge from the tap kept me going but these recharges became daily events at the least.
I have the greatest respect for all trades of that I can assure you and if any offense was given it was most certainly not intended.
Regards,
Les.
That's why I posted here. I wasn't trying to impose my inexpert view, I was postulating what has been bugging me hoping that some explanations would be forthcoming. Like why after two years would an extra expansion vessel help? Have I understood correctly that the 105 HE expansion vessel has a dual role?
I read on another forum to press the plunger in the valve and see if water, air or nothing came out but that was after the fact and the boiler had been removed.
I may have panicked a bit into the new boiler since my wife is convalescing after a major operation and a good supply of hot water is essential. The BAXI which has never missed a service, had been up and down in truth for a few months but when the DHW failed completely and the RED light came on for pump failure (which it was not) or loss of pressure I knew it was the latter and the gauge confirmed it. A recharge from the tap kept me going but these recharges became daily events at the least.
I have the greatest respect for all trades of that I can assure you and if any offense was given it was most certainly not intended.
Regards,
Les.
gas4you";p="1239180 said:
Hey Dave,
Your post says," LesD wrote:" but those insulting phrases were Tony's not mine!
No takers for the BAXI 105HE with a suspect expansion vessel that is stood stony cold in my garage.
Those with offers stand in line!
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Hi Tony,
Its broke it's not for sale but no one replied so I had to get your attention again. I intend to scrap it but my curiosity as an Engineer (Electrical I admit) has got the better of me and I would like to understand the ins & outs of what happened to the expansion vessel and why an extra one would have solved the problem. Academic it may be but it would draw a line under the matter for me.
Water under the bridge I know but I have a need to know to be satisfied if it can be.
The EXV can be imagined as two chambers separated by a rubber diaphragm which can flop to either side.
One side is for air and the other for water.
If the diaphragm is holed then there is water on both sides so no air to adsorb any expansion.
An external EXV reinstates a new vessel with air to adsorb expansion.
Tony
One side is for air and the other for water.
If the diaphragm is holed then there is water on both sides so no air to adsorb any expansion.
An external EXV reinstates a new vessel with air to adsorb expansion.
Tony
Ah I see the new external vessel replaces the function of the flawed internal one and hence was not needed from day one when the internal one was working OK.
Thanks that makes sense of it for me now.
Better to say it was not needed until the internal one failed !
On the Instant model, hot water is stored in the over sized EXV inside the boiler.
That may have seemed a good idea to someone at Baxi but the constant high temperature caused the rubber to fail. Luckily that is the only boiler to try that idea!
The idea is good but they should have used silicone rubber or nitrile or some material better suited to high temperatures.
Tony
On the Instant model, hot water is stored in the over sized EXV inside the boiler.
That may have seemed a good idea to someone at Baxi but the constant high temperature caused the rubber to fail. Luckily that is the only boiler to try that idea!
The idea is good but they should have used silicone rubber or nitrile or some material better suited to high temperatures.
Tony
Yes much better.
This explains the second function of this vessel that I had round my neck in an earlier post. Thanks again.
I have registered on more forum than I can remember over the years and this one is up among the best for excellent advice. What I cannot help noticing about this particular thread is that since October 2007 it has had over 6570 views and that's a whole lot of interest in BAXI 105HE problems. Maybe if some of those that viewed this thread, possibly because they have had similar issues, joined up and said so there would be enough momentum to present a case to BAXI.
With my family name and a younger member practising in the legal profession, who know where we could go!
Hi
Have exactly the same problem as LesD but can't fork oput £1000+ for a replacement at the mo!
My expansion vessel has failed (there is water coming out of the top up valve) and I know it is a case of removing the boiler from the wall to replace it. I never used the pre-heat setting as it caused the boiler to fire every ten minutes or so and thought this was a waste of energy for the sake of waiting ten seconds or so for hot water.
So I am going to fit an additional expansion vessel to replace the faulty one.
My question is does this need to be adjacent to the boiler i.e. on the main return pipework to the boiler or can it be installed anywhere on the system? I would have thought that the vessel will take up the expansion wherever it is on the system.
I have very little room in the boiler cupboard and therefore it would be easier to fit somewhere else on the system.
Have exactly the same problem as LesD but can't fork oput £1000+ for a replacement at the mo!
My expansion vessel has failed (there is water coming out of the top up valve) and I know it is a case of removing the boiler from the wall to replace it. I never used the pre-heat setting as it caused the boiler to fire every ten minutes or so and thought this was a waste of energy for the sake of waiting ten seconds or so for hot water.
So I am going to fit an additional expansion vessel to replace the faulty one.
My question is does this need to be adjacent to the boiler i.e. on the main return pipework to the boiler or can it be installed anywhere on the system? I would have thought that the vessel will take up the expansion wherever it is on the system.
I have very little room in the boiler cupboard and therefore it would be easier to fit somewhere else on the system.
It can be anywhere but ideally on the return pipe and not in a loft to freeze up.
Its possible to get squarish ones which about about 60mm thick.
Size needs to be related to volume of heating system ( number and type of rads ).
Tony
Its possible to get squarish ones which about about 60mm thick.
Size needs to be related to volume of heating system ( number and type of rads ).
Tony
Hi All, getting back to the original problem about the radiators heating when they are not supposed to be on ,as with the original post my dhw led is flashing and when i turn the temp.control down all is ok. My thinking is it is the divertor valve trouble ,is this correct, if so can the divertor valve be stripped and parts replaced,(could maybe need cleaned out and some tender loving care !!!!! or will i have to replace the whole valve
Thanks Billmccan
Thanks Billmccan
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Just to add this info.
I had a problem with losing pressure and having to fill all the time.
The problem was:
Diverter valve. Some metal from the heating system accumulated in there and got stuck between the seal and the body. It wasn't fully closing the CH when switched to DHW mode thus it was sucking the CH water through with the hot water and gradually emptying the heating system.
Removed the whole diverter assy, fitted the repair kit, gave it all a good internal clean and is now solved
Thought this could be useful
Been running for 12 years and repairs have cost around £250 in parts so far
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