Hi all
I have a Vaillant ecotec plus (ground floor) and an unvented cylinder (top floor). This is an s-plan with a downstairs ufh zone and a single 1st and 2nd floor radiator zone each zone controlled by a two port valve. We have had various issues with the installer of this system.
The latest issue is that whenever the ground floor UFH is on or the hot water is on the radiator zone on the 1st and 2nd floor gets hot.
This is being caused by reverse circulation (the return pipes of the rads get hot when the h/w or ufh is on but the red zone is off). The cylinder return is not the last connection before the boiler - the rads and ufh tee in after it.
The installer is returning to run a new pipe back from the boiler to the cylinder upstairs to ensure there cylinder is the last connection before the boiler. I have a couple of questions I would like to ask to ensure the installer does what is required:
1. This boiler requires an ABV and this is installed by the cylinder in the loft. As currently stands this is after the pump and before both the h/w and rad/ufh zone valves. Is this correct?
2. Should the abv be the last connection before the boiler or should the last connection be the cylinder return?
3. Is there any requirement for the returns from the ufh and rad to common together some distance before the cylinder return or is it simply enough that they connect in the correct order regardless of how close to each they do so?
4. Is there a requirement for the return from the ufh and the common return from the rads to connect together in any specific order or again is it just “they must do so before the cylinder return”
Apologies for all the questions but I want to make sure, given other issues we have had which I won’t go into here, that the work that needs to be carried out is done correctly this time.
Thanks for your time, I really appreciate it
I have a Vaillant ecotec plus (ground floor) and an unvented cylinder (top floor). This is an s-plan with a downstairs ufh zone and a single 1st and 2nd floor radiator zone each zone controlled by a two port valve. We have had various issues with the installer of this system.
The latest issue is that whenever the ground floor UFH is on or the hot water is on the radiator zone on the 1st and 2nd floor gets hot.
This is being caused by reverse circulation (the return pipes of the rads get hot when the h/w or ufh is on but the red zone is off). The cylinder return is not the last connection before the boiler - the rads and ufh tee in after it.
The installer is returning to run a new pipe back from the boiler to the cylinder upstairs to ensure there cylinder is the last connection before the boiler. I have a couple of questions I would like to ask to ensure the installer does what is required:
1. This boiler requires an ABV and this is installed by the cylinder in the loft. As currently stands this is after the pump and before both the h/w and rad/ufh zone valves. Is this correct?
2. Should the abv be the last connection before the boiler or should the last connection be the cylinder return?
3. Is there any requirement for the returns from the ufh and rad to common together some distance before the cylinder return or is it simply enough that they connect in the correct order regardless of how close to each they do so?
4. Is there a requirement for the return from the ufh and the common return from the rads to connect together in any specific order or again is it just “they must do so before the cylinder return”
Apologies for all the questions but I want to make sure, given other issues we have had which I won’t go into here, that the work that needs to be carried out is done correctly this time.
Thanks for your time, I really appreciate it
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