Central heating flow/ heat issues

[Dan1983]

Evening all,

Hope everyone had a good Christmas and new year!

 

Unfortunately since the previous cold spell we have had heating issues in our new build.

 

Its been fine from August to start of December (albeit slight whistling type noise from the cylinder at times)

 

We have a Worcester system boiler with Gledhill stainless es cylinder (unvented).

 

Issue started in December when a bath was run, no issues but then run out of hot water when bath was topped up (never ran out of hot water before)

Assumed the wife had just emptied the cylinder and no issues.

 

From that point on hot water is hit and miss (Occasionally using Emerson)

Central heating seems lethargic, downstairs is UFH, the stats hit there set points but takes longer than before and floor is only warm in random areas (was not like this before)

Upstairs rads barely get warm at all.

 

Cylinder area seems to have gotten noisier also.

With this in mind I thought it was an air issue or problem with the 2 port valves.

 

Had the builder back out, everything bled and checked valves and was told no issues.

He mentioned the boiler pump would run for a few mins then stop, then cut back in again so said I needed to get Bosch engineer out as boiler fault.

 

Engineer came out just before Christmas which was great and thought it maybe a software or pump fault so replaced both items.

This unfortunately made no difference.

The Bosch engineer is saying the boiler return is only ever warm at best which points towards a blockage in the circuit.

Is this common on a new build?

Awaiting a reply from the builder now as Engineer saying a hot flush needs to be done.

 

I will try and upload two videos of the cylinder area noise.

Could you let me know if this is normal as I’m sure it’s not!

 

Many thanks for any input, sorry for the essay!

Just don’t want to get fobbed off by the builder/plumber next visit!

[Dan1983]

First video is the whistling noise which is quite loud downstairs!

From the vid the noise goes when I turn the upstairs heating stat up, then comes back when I turn it down.

 

The hot water is on timed so think cylinder was also heating at this time

 

 

 

Edited January 1, 2023 by Dan1983

[Dan1983]

Not sure what this noise is and it’s only happened a couple of times!

 

 

[Dan1983]

Incase anyone else gets the same symptoms on a greenstar 4000

After back and forth with plumber vs Bosch 2nd Bosch visit heat exchanger was replaced and this looks to have sorted the issue!

[NickK]

Thanks for sharing. Glad it got sorted.

[Dan1983]

Being told by others it’s not the first time the heat exchangers have caused issues on these but Bosch will not offer recall.

Annoyingly it’s started playing up again in the cold weather

Makes a droaning sound for minute or so after it has fired up.
Kitchen not making stat set point and boiler not always firing when heat demand shows on stats 

Going to ask engineer on Tuesday about rejecting the boiler as it’s like triggers broom already and it’s just over 6 months old!