Cylinder return valve?

[Eddiez]

Ever since the cylinder return balancing valve has been messed with by my kids it hasn't been hot like before what can I do? (as previously I've been told to leave it fully open )

 

[PETE 123]

Are you sure its the return thats fully open or a system bypass.

 

[Eddiez]

Are you sure its the return thats fully open or a system bypass.

Pretty sure it's the return

 

[PETE 123]

some pics may help you problem.

 

[Eddiez]

some pics may help you problem.

There it is

 

[ShaunCorbs]

Didn’t I say 3 full turns closed should do it from fully open ?

 

[Eddiez]

Didn’t I say 3 full turns closed should do it from fully open ?

The water still continues to be warm but not hot as it used to be

 

[ShaunCorbs]

Do one more turn then

 

[Eddiez]

Do one more turn then

So in total four turns open from closed position?

 

[ShaunCorbs]

Correct see what the temp is like might need 1/2 a turn etc

 

[fowlerboi]

If your kids have played with the gate valve is it also likely they've adjusted the cyl stat?

 

[Eddiez]

If your kids have played with the gate valve is it also likely they've adjusted the cyl stat?

I've checked and it hasn't been touched

 

[John.g]

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.

 

[Eddiez]

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.

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?

 

[John.g]

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.

 

[PETE 123]

I the white box hw zone valve opening and closing when timer set to come on turn cylinder stat up down to check as zone valve could be at fault .

 

[Eddiez]

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.

Thanks I'll try it out and get back to you!

 

[Last Plumber]

Is there a vent off flow?

 

[Eddiez]

Is there a vent off flow?

I'm not sure what that is,What does it look like?

 

[Last Plumber]

I'm not sure what that is,What does it look like?

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.

 

[John.g]

Should be able to slacken the pipe at the top where its connected to the coil and pull it back a little to allow the air to escape.

 

[Eddiez]

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.

Yes there is a vent with a cap on it. When it is removed air is removed

 

[John.g]

Does 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.

 

[Eddiez]

Does 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.

Yes the air stoped after a few seconds and the pressure on boiler is at 1.2

 

[John.g]

I have a 150L HW cylinder with a standard 0.65M2 coil, I took some readings off it when heating a stone cold cylinder from 13C to 60C years ago and my calcs showed that the coil averaged ~ 5kw output from cold to hot, ~ 8kw when cylinder cold and ~ 2kw with a hot cylinder, boiler temp was/is 70C.
Based on that, to heat a 100L cylinder from say 10C to 55C should take ~ 1 hour. A 150L 1.5hrs, 200L, 2hrs etc. These would now be considered very very slow heat up times.
So knowing the volume of your HW cylinde you can get a rough idea from my numbers the heat up time required.