Quick question regarding heating pumps

[Readingplumber]

Hi Again,

Do normal heating pumps when switched off allow water through?

My line of thought would be on a zoned heating system replace the zone valves with pumps obviously if they let water through when off it wouldnt work?

Thanks

 

[Puddle]

Hi Again,

Do normal heating pumps when switched off allow water through?

My line of thought would be on a zoned heating system replace the zone valves with pumps obviously if they let water through when off it wouldnt work?

Thanks

They most certainly do,so nice thought but would not work

 

[migoplumber]

ive wangled it before ! not good for maintenance and you need a clean system, however if you dont like zone valves :-

if your pipework is 22mm and your pump is fitted on said pipework, install directly below the pump a non return valve (in the correct flow position) but importantly use the next size up, ie. in this case 28mm with reducers to 22mm pipework.

as said above, only really any good on a new system with no debris, and depending on the size of other pumps in system you may get a small amount of bypass on unrequired zones.

done it, cos i had to. wanted absolute minimum power consumption on a 12 volt solar system !