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 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

 

[Racheal1256]

How long roughly should this take to heat up? The boiler has been on most of the day so far and the temp control is still clicking at about 45.
Both pipes labelled coil 1 are very hot and even the cold feed is rather warm now.

 

[Last Plumber]

How long roughly should this take to heat up? The boiler has been on most of the day so far and the temp control is still clicking at about 45.
Both pipes labelled coil 1 are very hot and even the cold feed is rather warm now.

What temperature is the boiler set to?

 

[Racheal1256]

What temperature is the boiler set to?

Boiler is on 60, cylinder is also on 60

 

[Last Plumber]

Boiler is on 60, cylinder is also on 60

Something isn't right obviously but I don't think it is going to be cured on a forum. I think you need to get someone in to it.
A cylinder that size with that coil rating should get from 10C to 60C in an hour.
If you didn't use it then it would stay hot a relatively long time.

Granted, you will lose heat on a secondary circuit but not to the extent you described.

 

[ShaunCorbs]

If it’s just hot water on and a 25kw boiler an hour if 15kw boiler 2-3 hours

 

[Racheal1256]

Something isn't right obviously but I don't think it is going to be cured on a forum. I think you need to get someone in to it.
A cylinder that size with that coil rating should get from 10C to 60C in an hour.
If you didn't use it then it would stay hot a relatively long time.

Granted, you will lose heat on a secondary circuit but not to the extent you described.

Thank you for all your help. I’m still waiting for proof of competency from the developer/builder and they are the same people who I’ve reported the problem to and I’m awaiting a response! I can’t get my own plumber out, as the developer will no longer be responsible. Hence me reaching out on here.
You’ve been a great help and very patient with me. Thank you again.
I’ll let you know what the problem was once we finally get to the bottom of it.

 

[Racheal1256]

If it’s just hot water on and a 25kw boiler an hour if 15kw boiler 2-3 hours

If it’s just hot water on and a 25kw boiler an hour if 15kw boiler 2-3 hours

Yes, only got hot water on and it is a 25kw boiler.
The plumbers have changed the temperature control on the cylinder last month too!

Thank you for all your help. I’m still waiting for proof of competency from the developer/builder and they are the same people who I’ve reported the problem to and I’m awaiting a response! I can’t get my own plumber out, as the developer will no longer be responsible. Hence me reaching out on here.
You’ve been a great help and very patient with me. Thank you again.
I’ll let you know what the problem was once we finally get to the bottom of it.

 

[Last Plumber]

Yes, only got hot water on and it is a 25kw boiler.
The plumbers have changed the temperature control on the cylinder last month too!

Thank you for all your help. I’m still waiting for proof of competency from the developer/builder and they are the same people who I’ve reported the problem to and I’m awaiting a response! I can’t get my own plumber out, as the developer will no longer be responsible. Hence me reaching out on here.
You’ve been a great help and very patient with me. Thank you again.
I’ll let you know what the problem was once we finally get to the bottom of it.

One last thing.
On the left is a gate valve (red wheel). Is that on the return from the coil? Is it open?

 

[Racheal1256]

One last thing.
On the left is a gate valve (red wheel). Is that on the return from the coil? Is it open?

Yes it is

 

[Racheal1256]

One last thing.
On the left is a gate valve (red wheel). Is that on the return from the coil? Is it open?

Apologies, yes it’s open and on the return coil pipe