Discuss France - British CH system help sought! in the USA Plumbers Advice area at PlumbersForums.net

Lot lovely area been to St Sulpice several times.
From what i can see from the pictures, blimey what a mess. But here goes try to make some sense of it all, mains unvented hw cylinder, that's what the blue expansion vessel is for. The other red one is for your central heating circuit. Sorry if you already know this. Under UK G3 rules it would appear that the safety release devices are not installed as per G3 requirement, these are all for safety . You can see the cold composite vale body (large black shroud) has a pressure relief that tees into pipe running across top of cylinder meets another pressure relief valve before it discharges into tundish (Not good).
As you see on last picture there is a cylinder stat albeit not as per G3 regs this should have a electrical safety cut out which kicks in if thermostat fails, which would normally be combined with the cut out correctly called Combined cylinder thermostat and `ECO (Energy cut out). You have a standard thermostat very basic, not suitable for this system really. The valve under the blue vessel would control yr hot water temp and timings as to when to come on and off (This is likely where temperature issue lies), as for the motorised valve with cover missing between the vessels can't quite work out where it is going to or coming from below, as pipe disappears behind blue vessel so I can't make comment. I would say you need to get a replacement two port to replace the motorised valve beneath the blue vessel that controls yr hot water temperature. Plus strongly recommend a service for the cylinder and all the components.
One other observation unvented cylinders also have a pressure temperature relief valve, can't make out one from the pictures. All for safety.
 
Right, wouldnt have been a best mate with a result like that!
[automerge]1580958062[/automerge]
Lot lovely area been to St Sulpice several times.
From what i can see from the pictures, blimey what a mess. But here goes try to make some sense of it all, mains unvented hw cylinder, that's what the blue expansion vessel is for. The other red one is for your central heating circuit. Sorry if you already know this. Under UK G3 rules it would appear that the safety release devices are not installed as per G3 requirement, these are all for safety . You can see the cold composite vale body (large black shroud) has a pressure relief that tees into pipe running across top of cylinder meets another pressure relief valve before it discharges into tundish (Not good).
As you see on last picture there is a cylinder stat albeit not as per G3 regs this should have a electrical safety cut out which kicks in if thermostat fails, which would normally be combined with the cut out correctly called Combined cylinder thermostat and `ECO (Energy cut out). You have a standard thermostat very basic, not suitable for this system really. The valve under the blue vessel would control yr hot water temp and timings as to when to come on and off (This is likely where temperature issue lies), as for the motorised valve with cover missing between the vessels can't quite work out where it is going to or coming from below, as pipe disappears behind blue vessel so I can't make comment. I would say you need to get a replacement two port to replace the motorised valve beneath the blue vessel that controls yr hot water temperature. Plus strongly recommend a service for the cylinder and all the components.
One other observation unvented cylinders also have a pressure temperature relief valve, can't make out one from the pictures. All for safety.
Thanks very much, yes what a pigs ear, none of which could be seen when we bought. There appears to be a safety cut out on the top of the tank (the red can) it only has a basic reset button inside it. There doesnt appear to be a tank stat connected to the boiler, the stat in the photo appears to be connected under the insulation to the immersion. the immersion cable is simply connected to a 3 pin plug. Immersion seems to work well. The motorised valve without the cover operates on the room stat, this appears to function to shut off circulation to the rads. I'll have another look at the valve on top of the tank. There is a pressure relief valve and a dial on the cylinder, pressure is running a bit high at the moment. If I could shut off the hot water heat on the boiler I'd be happy to just use the immersion. I think next year I need to replace this boiler installation with a french installation as I'm pretty unhappy with it as it is, its not in the budget for this year! Thanks for your informative reply are you coming to the lot this year?!
 
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Hello, wish I was in the Sth of France weather here is horrendous at the moment.
Had another look at yr images. The valve that controls yr hot water is the danfoss one tucked around the back. This is ultimately controlled by a thermostat which is from what I can make out is likely to be the one located just above the immersion on the side of the tank. If you were to take the lid off the white immersion there would be a thermostat in there. So I would investigate a bit further re the wire. In essence the way it works is that the programmer would liven up when in the on period which would energise yr thermostat which in sequence if there was call for heat it would open yr motorised valve (The danfoss, rare as rocking horse poo, but easily interchangeable with a better known make such as yr honeywell, which has the cover missing!!). When cylinder gets to temperature thermostat will switch off power to valve closing it, this could be a spring close but in some cases may be powered. Don't know how the danfoss works, admittedly never seen one
I can't make out what the redring (On top of cylinder) is for, not clear on images.
Re pressure the composite valve (black shroud) is generally an all in one affair of non return valve incoming water pressure reducing and pressure relief and strainer. Yrs has a separate pressure relief with another pressure gauge. These are normally set at 3.0bar no more, if there was excess pressure this would release and should flow to a 'tun dish" not impeded Yrs meets another pressure relief above the receptacle resembling somewhat a tun dish. I would at a guess image one of the valves back down the line was letting by and in his wisdom thought I know Ill stick another pressure valve on no problem.
Closing paragraph- re investigate thermostat and the danfoss valve that's where yr hot water temp lies.
Save yr pennies as ap and get a french one put in much less aggro if it goes wrong.
There are a lot of bits on there which are unnecessary and appear to be get arounds not ideal especially when yr miles away from blighty.
all the best, the cowboy has left the village.
 

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Lot lovely area been to St Sulpice several times.
From what i can see from the pictures, blimey what a mess. But here goes try to make some sense of it all, mains unvented hw cylinder, that's what the blue expansion vessel is for. The other red one is for your central heating circuit. Sorry if you already know this. Under UK G3 rules it would appear that the safety release devices are not installed as per G3 requirement, these are all for safety . You can see the cold composite vale body (large black shroud) has a pressure relief that tees into pipe running across top of cylinder meets another pressure relief valve before it discharges into tundish (Not good).
As you see on last picture there is a cylinder stat albeit not as per G3 regs this should have a electrical safety cut out which kicks in if thermostat fails, which would normally be combined with the cut out correctly called Combined cylinder thermostat and `ECO (Energy cut out). You have a standard thermostat very basic, not suitable for this system really. The valve under the blue vessel would control yr hot water temp and timings as to when to come on and off (This is likely where temperature issue lies), as for the motorised valve with cover missing between the vessels can't quite work out where it is going to or coming from below, as pipe disappears behind blue vessel so I can't make comment. I would say you need to get a replacement two port to replace the motorised valve beneath the blue vessel that controls yr hot water temperature. Plus strongly recommend a service for the cylinder and all the components.
One other observation unvented cylinders also have a pressure temperature relief valve, can't make out one from the pictures. All for safety.
Thank you very much for your very helpful reply, you have confirmed my suspicions in regards to the installation and I agree that this needs to be replaced with a local system, but that will have to wait for the budget! I have disassembled the valve (as far as motor is concerned), the motor is a replacement and has failed as well. I beleive the valve is also stuck, so will be replaced with a like for like. Thanks once again for the time that you took for a helpful explaination
 
You have independent control of heating and hot water. Quite likely its one of the valves failed. I don't know if this particular valve has a removable head? but it looks like the motor has been changed in the past. Test the motor for continuity. It could be the valve its self jammed open. You might get away with just the motor? I would say your system need a major sort out.
 

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