Hi
I have a 'standard' open vented gas fired installation: the output from the boiler splits in two, one goes to my DHW cylinder (two floor up), the other to the radiators. There is one pump, currently on the return to the boiler. The radiator circuit has an electric valve so it can be controlled but the DHW circuit has no valve and is always on when the boiler runs.
I want to have seperate control of the DHW and put a stat on the cylinder for efficiency reasons, but I want to achieve this with minimum pipework changes (would require knocking through various false walls...)
The flow to the cylinder (22mm) is also acting as the F&E/vent for the system (the F&E tank is about 1m higher than the cylinder) - so that has to be kept clear (no valves or pumps) as I understand.
I have a thought of installing a second pump right next to the cylinder on the branch off the F&E pipe to pump water through the DHW circuit, allowing a free run of F&E pipe from boiler to vent. I would propose also putting a one-way valve in line with the new pump. I will move the existing pump to be only on the CH circuit, along with a one-way valve, and remove the existing electric valve that is there. Then I can arrange the controls to power one or both pumps depending on whats required.
Will this work? What should I be worried about in this arrangement? Im thinking : is it safe to fit a pump inlet about 1m below the F&E tank? If both pumps are running will this cause problems?
Any thoughts appreciated!
Regards
John
I have a 'standard' open vented gas fired installation: the output from the boiler splits in two, one goes to my DHW cylinder (two floor up), the other to the radiators. There is one pump, currently on the return to the boiler. The radiator circuit has an electric valve so it can be controlled but the DHW circuit has no valve and is always on when the boiler runs.
I want to have seperate control of the DHW and put a stat on the cylinder for efficiency reasons, but I want to achieve this with minimum pipework changes (would require knocking through various false walls...)
The flow to the cylinder (22mm) is also acting as the F&E/vent for the system (the F&E tank is about 1m higher than the cylinder) - so that has to be kept clear (no valves or pumps) as I understand.
I have a thought of installing a second pump right next to the cylinder on the branch off the F&E pipe to pump water through the DHW circuit, allowing a free run of F&E pipe from boiler to vent. I would propose also putting a one-way valve in line with the new pump. I will move the existing pump to be only on the CH circuit, along with a one-way valve, and remove the existing electric valve that is there. Then I can arrange the controls to power one or both pumps depending on whats required.
Will this work? What should I be worried about in this arrangement? Im thinking : is it safe to fit a pump inlet about 1m below the F&E tank? If both pumps are running will this cause problems?
Any thoughts appreciated!
Regards
John
