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Pretty sure it's the returnAre you sure its the return thats fully open or a system bypass.
There it issome pics may help you problem.
The water still continues to be warm but not hot as it used to beDidn’t I say 3 full turns closed should do it from fully open ?
So in total four turns open from closed position?Do one more turn then
I've checked and it hasn't been touchedIf your kids have played with the gate valve is it also likely they've adjusted the cyl stat?
Hi there the boiler flow is set to 75 degrees which is the max and for the return coil it is quite hot when the hot water is on. And to confirm one full turn is adequate?What is the boiler flow temperature set to? and are you allowing it enough time to reheat the cylinder??.
If you feel the return (coil) temperature is it hot/warm or only lukewarm?.
Regarding the return valve, anything more than 1 full turn open from fully shut is quite adequate.
Thanks I'll try it out and get back to you!You can allways open it fully, if you all ready have it 4 turns open then its almost fully open anyway. If the cylinder is taking hours to heat up then the coil may have scale if its years old.
I'm not sure what that is,What does it look like?Is there a vent off flow?
Some way of air getting out or being let out. If there is a lack of water in the coil because air is trapped, it won't work.I'm not sure what that is,What does it look like?
Yes there is a vent with a cap on it. When it is removed air is removedSome way of air getting out or being let out. If there is a lack of water in the coil because air is trapped, it won't work.
Yes the air stoped after a few seconds and the pressure on boiler is at 1.2Does the air stop after a few seconds or does it take longer??.
If you have a sealed system ensure boiler pressure at 1/1.5bar, if open vented ensure the (small) F&E tank is "full" of water.
Reply to the thread, titled "Cylinder return valve?" which is posted in UK Plumbers Forums on Plumbers Forums.
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