Hi, I hope someone can help out with a problem I've been unable to solve thus far.
I get no Hot water, only cold at normal flow rate , when boiler set to Central Heating & Hot Water, or Hot water only. The Central Heating (rads) work.
Its a 20 year old system, indirect hot water system, with Potterton Fuelsaver 60F boiler on ground floor, pump & cylinder on 1st floor, expansion feed tank in loft.
There is 1 dual port motorised valve (MV) which is working & is not part of the cylinder supply.
The pipe feeding the cylinder coil is hot going into cylinder, but cool on the pipe coming out of cylinder coil (at HWCyl>---V1).
V1 is a valve that is turned on.
If I close the Gatevalve gV1, then the pipe at V1 does get hot so I believe there is water flowing through it at least some of the time. If I then reopen gV1, pipe at V1 goes cool again, but after say 4 minutes will get hot again, then cool again.
It sounds as if there is air swishing through the pipes & pump.
Every few minutes I can hear banging noises (air?) from pipes.
I really thought this was a problem caused by air in the primary circuit/cylinder coil.
I closed valve V1 and opened the cylinder side connection of V1, letting some water out hoping this would clear any air in coil. (Perhaps there is a vacuum).Also I noticed that the water which came out of V1 connection was clean with no sludge.
I have also been opening up the bleed valve which never releases any air.
The expansion tank is full & I dont think there is a problem with the water feed from the tank.
Can anyone tell what it seems like the problem is, & if it is air in the system how on earth do you purge it out effectively.
I I I
I I I--->ToRads
HWCyl->-- V1------------I I
I Pump VentPipe
_____I I I
I I I-----------------I
I I I
I I I FeedfromExpTank
I I I I
I I I-------------------I
I I I
I I I
Any advice greatly appreciated