Grundfos Pump Plan valves sticking
- Thread starter oilman
- Start date
I was thinking something similar in removing the valves from the pump. When you say cut in a flap valve, are you meaning one put into a pipe run?
I have replaces the valves in the pump previously, which worked for a few days. It is used in a W/flow combi. They say the arrangement is very reliable. I see it as a potential problem with the construction of the valve, and the reality being it is unlikely the system will remain clean.
I have replaces the valves in the pump previously, which worked for a few days. It is used in a W/flow combi. They say the arrangement is very reliable. I see it as a potential problem with the construction of the valve, and the reality being it is unlikely the system will remain clean.
Yes roy, unfortunatley you do have to cut the pipe, the flap check valves are bulky and need 22mm iron to coppers, so could be a tight fit in a combi.
The old flap type check valves are bullet proof, all of the so called heating type spring loaded ones I have looked at are to restrictive and prone to collect crud.
I only use the pump plan when converting from SMC if the wirring is hidden in the fabric of the building , and the old cylinder stat is on 2 core.
The old flap type check valves are bullet proof, all of the so called heating type spring loaded ones I have looked at are to restrictive and prone to collect crud.
I only use the pump plan when converting from SMC if the wirring is hidden in the fabric of the building , and the old cylinder stat is on 2 core.
It's no problem fitting the valve in the CH return as there's plenty of room outsite the boiler. The DHW might be interesting.
The pump plan is sold as having the benefit of getting rid of electric valves which could suffer failed motor, sticking mechanism, etc. They are not half such a maintenance problem as two tiny valves which are sensitive to inevitable crud.
With the flap valve fix I can use a desludger, drain, add valves and a Magnaclean and refill. The rads aren't blocked, so there's not much excuse for a powerflush, except on the DHW circuit to clean out the boiler.
Thanks for your help.
The pump plan is sold as having the benefit of getting rid of electric valves which could suffer failed motor, sticking mechanism, etc. They are not half such a maintenance problem as two tiny valves which are sensitive to inevitable crud.
With the flap valve fix I can use a desludger, drain, add valves and a Magnaclean and refill. The rads aren't blocked, so there's not much excuse for a powerflush, except on the DHW circuit to clean out the boiler.
Thanks for your help.
I would fit the check valves on the flows coming out of the pump, within the first foot or so if practical.
What do you think of the warmflow combi ?, I have only worked on their regular and condensing kit which was straightforward enough.
What do you think of the warmflow combi ?, I have only worked on their regular and condensing kit which was straightforward enough.
Twin head pump is not good, the exp vessel flexi is very short, and the exp vessel has a really awkward mount. It's nearly as bad as the heatslave to work on, but not as bad as the wallstar.
DHW NRV will be a pig to fit just after the pump as there is just 4" of pipe, and it is a downward flow.
Will investigate screwing the CH valve on the pump adaptor.
DHW NRV will be a pig to fit just after the pump as there is just 4" of pipe, and it is a downward flow.
Will investigate screwing the CH valve on the pump adaptor.
D
Doctor Drivel
A Magnaclean on the return to the boiler should do it and replace/clean the pump check valves. They really do grab the crud. I just opened one after two years of installation, and with X-400 in, and the level of crud caught was quite high. This is what was on the rads even after CH cleaner was used before a boiler change. This would have reduced the boiler tube sizes and got on the pump and other equipment in the system. Certainly it would catch crud from forming on check valves.
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Hi all. I have come across one of these today where the heating circuit upstairs is not heating up but downstairs rads are ok. Where are the NRV valves installed on this? Cheer. I cannot find anything online.
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This system also has a 2 port zone valve on the output to the hesting which has been jammed in the manual position. Is it the feed and vent that go into the top of the pump? This has the hot water circuit on the left and the heating circuit on the right.
It is the 1st time I have come across one in 16 years!
Thanks all
It is the 1st time I have come across one in 16 years!
Thanks all
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