In our recently purchased house, the CH system is open vent (pumped) with gravity feed to hot water and bathroom radiator.
Last year, so I m told, the previous owners had TRVs fitted to the two main bedrooms, and the two living room radiators. This leaves the 3rd box/bed room, hallway and bathroom without TRVs.
The are Drayton 15mm angled TRV4's by the way
If all the TRVs are fully open (i.e. on max) then no problem. However, if the TRV is closed down to 3 or 4 then everytime the heating comes on (i.e.pumped) then the two upstairs radiators with TRVs become noisy as if water is trying to be forced through i.e. a swishing noise rather than gurgling or banging - a similar sound to that when you restrict the flow of water from out of a hosepipe with your finger. Then, after a several seconds you also start to hear other noises that are more like gurgling go through the radiator.
I have bled the system over and over. I was advised to check in the header tank to see if water was being pumped up through the vent pipe and to also check to see if air was being sucked through the vent pipe - but neither applies.
A neighbour suggested my pump was too fast but it only has 3 settings, it is in the middle and I already have to use Fernox F2 silencer to stop kettling', I fear slowing the pump would make that worse. It's not maga bad and improved a lot since I flushed he system, but added the F2 just to make sure along with the inhibitor.
Any suggestions?
Last year, so I m told, the previous owners had TRVs fitted to the two main bedrooms, and the two living room radiators. This leaves the 3rd box/bed room, hallway and bathroom without TRVs.
The are Drayton 15mm angled TRV4's by the way
If all the TRVs are fully open (i.e. on max) then no problem. However, if the TRV is closed down to 3 or 4 then everytime the heating comes on (i.e.pumped) then the two upstairs radiators with TRVs become noisy as if water is trying to be forced through i.e. a swishing noise rather than gurgling or banging - a similar sound to that when you restrict the flow of water from out of a hosepipe with your finger. Then, after a several seconds you also start to hear other noises that are more like gurgling go through the radiator.
I have bled the system over and over. I was advised to check in the header tank to see if water was being pumped up through the vent pipe and to also check to see if air was being sucked through the vent pipe - but neither applies.
A neighbour suggested my pump was too fast but it only has 3 settings, it is in the middle and I already have to use Fernox F2 silencer to stop kettling', I fear slowing the pump would make that worse. It's not maga bad and improved a lot since I flushed he system, but added the F2 just to make sure along with the inhibitor.
Any suggestions?
