Unvented Hot Water System

[Rachael1278]

Hi, I’ve purchased a new build property and had a few issues with the unvented hot water system. I’ve now asked the developer, builder and plumber for proof of G3 certificate of the plumbers but have been told they have no need to show me this. I’ve searched the gas safe register and it’s not showing on their profile, however this doesn’t tell me definitely that they do not hold the qualification.
Anybody know what I can do to check this? Building control who signed off the house are basically unhelpful/uninterested.

 

[ShaunCorbs]

Yes either one is fine

And it returns into the secondary port eg that pipe what goes into the cylinder from the pump

 

[Racheal1256]

Yes either one is fine

And it returns into the secondary port eg that pipe what goes into the cylinder from the pump

Ah, I thought that’s where it came out, not went back in!! I am clueless!
Will try turning and see what happens

 

[ShaunCorbs]

Hope this helps

Normally fitted to bathrooms / taps the other end of the house / far away from the cylinder as you have to run the hot tap for a while to get hot water due to the distance and the cold water in the pipe as it’s unlagged/ gone cold etc

 

[Racheal1256]

Hope this helps

Normally fitted to bathrooms / taps the other end of the house / far away from the cylinder as you have to run the hot tap for a while to get hot water due to the distance and the cold water in the pipe as it’s unlagged/ gone cold etc

View attachment 79190

Thanks Shaun 😊

 

[Last Plumber]

You haven't got the valve I wanted to see but never mind. Once you have closed the valve Shaun asked you to, close the one on the very top of the cylinder too. There should be no water from hot taps after an initial short run off.
Open them both again once you have found out whether it stops running or not.

 

[Racheal1256]

Thanks Shaun 😊

Ah, I thought that’s where it came out, not went back in!! I am clueless!
Will try turning and see what happens

Evening Shaun, turned the bottom one. Water temp felt no different 😢

 

[ShaunCorbs]

but did you reheat the cylinder for an hour?

 

[Racheal1256]

You haven't got the valve I wanted to see but never mind. Once you have closed the valve Shaun asked you to, close the one on the very top of the cylinder too. There should be no water from hot taps after an initial short run off.
Open them both again once you have found out whether it stops running or not.

Evening, the water stopped after the initial run off as you said.

 

[Racheal1256]

Evening Shaun, turned the bottom one. Water temp felt no different 😢

Ah, I am silly aren’t I!! I will try this again now and let you know in the morning

 

[ShaunCorbs]

And if you can keep a note on how long the boiler is fired / on

 

[Racheal1256]

Ah, I am silly aren’t I!! I will try this again now and let you know in the morning

Good morning,
So, the hot water was on from 6-7am, just tried hot water and it’s probably a little warmer but still not hot as it should be.
I did notice that the secondary return pipe where it enters the cylinder was hot to touch when brass valve under the pump was turned off but when I turn it back to open it instantly goes cold. No idea if this means anything.

Thank you.

 

[ShaunCorbs]

Right now turn turning the lever valve off at the top of the cylinder eg the pipe leaving the centre top of the cylinder and the pump one keep that off aswell please

 

[Racheal1256]

Right now turn turning the lever valve off at the top of the cylinder eg the pipe leaving the centre top of the cylinder and the pump one keep that off aswell please

No water runs out of the hot taps when I do this

 

[ShaunCorbs]

Correct but does the cylinder heat up / you have hotter water, if you do have hotter water that means water is flowing out of your cylinder all the time maybe

Also the red valve on the left wall just higher than the immersion is this open?

 

[Racheal1256]

Correct but does the cylinder heat up / you have hotter water, if you do have hotter water that means water is flowing out of your cylinder all the time maybe

Also the red valve on the left wall just higher than the immersion is this open?

So am I to turn of the lever on the top of the cylinder, turn the boiler on, wait a while, turn the lever back to open and test the water temp from the tap?
Red valve to the left is open.
Thank you for your patience

 

[ShaunCorbs]

Yes your testing if the cylinder will heat up at all when you re open the top lever valve after an hour and it gets instantly hot around 6” above the cylinder/ as high as you can feel there’s a problem

 

[Racheal1256]

Yes your testing if the cylinder will heat up at all when you re open the top lever valve after an hour and it gets instantly hot around 6” above the cylinder/ as high as you can feel there’s a problem

Yes your testing if the cylinder will heat up at all when you re open the top lever valve after an hour and it gets instantly hot around 6” above the cylinder/ as high as you can feel there’s a problem

Ok, all turned to off and boiler set to constant. Pipes that are currently hot I’ve detailed on the attached picture. I will give it an hour and the open to lever, feel pipes again and run hot tap.

Red-hot
Orange - warm
Blue - cold

 

[Racheal1256]

Ok, all turned to off and boiler set to constant. Pipes that are currently hot I’ve detailed on the attached picture. I will give it an hour and the open to lever, feel pipes again and run hot tap.

Red-hot
Orange - warm
Blue - cold

Yes your testing if the cylinder will heat up at all when you re open the top lever valve after an hour and it gets instantly hot around 6” above the cylinder/ as high as you can feel there’s a problem

So, after an hour I turn the lever back on. Hot water draw off pipe got warmer (not red hot) to touched after a few minutes. No hot water taps have been turned on at this point.
The coil 1 pipe at the very bottom of the cylinder is now also very hot to touch and the cold feed pipe at the bottom is tepid, whereas before it was stone cold.

 

[ShaunCorbs]

Now try running hot water

 

[Racheal1256]

Now try running hot water

The water does feel hotter.

 

[ShaunCorbs]

Right ok shut that red valve again and turn the hot water on eg heat up and leave it until it finishes eg fully heats up the cylinder you can tell this by moving the stat it’s on 60 ish now if it doesn’t click lower than this it’s fully heated

 

[Racheal1256]

Right ok shut that red valve again and turn the hot water on eg heat up and leave it until it finishes eg fully heats up the cylinder you can tell this by moving the stat it’s on 60 ish now if it doesn’t click lower than this it’s fully heated

Ok, done that. The stat clicked when I turned it down at about the 45 marker, turned back to 60.
Will the ignition/flame light go off on the boiler when it’s fully hot?

 

[Racheal1256]

Ok, done that. The stat clicked when I turned it down at about the 45 marker, turned back to 60.
Will the ignition/flame light go off on the boiler when it’s fully hot?

Red lever on top of cylinder is turned off, boiler is on constant for HW but no boiler flame light has come on?

 

[Racheal1256]

Red lever on top of cylinder is turned off, boiler is on constant for HW but no boiler flame light has come on?

Boiler light came on, I was just impatient!
See below video of me turning the temp switch.
Does this mean water temperature inside cylinder is only 45 degrees ish

 

[ShaunCorbs]

Yes it’s upto around 45 dc correct