Hot water from Valliant Boiler

[Margaret T]

Is that Luke warm with heating on or just hot water only?

The water is only Luke warm only. ....
So before testing, the water was like warm, the immersion was off and made sure the water was cold where possible.

The hive pressed hot water boost 30 minutes at 25 degrees. Duration of 14 minutes remaining, the water was only Luke warm. And the full 30 minutes, the water was only Luke warm. Felt the pipe work surrounding the hot water cylinder and it was warm / cold. The boiler displayed 75 reading on screen with 1.9 bar.

I also noted when I pressed cancel hot water on the hive, the drayton zone valve - the black clip slides downwards.

Test number 2.
Immersion switch off.
Hive boost both hot water and heat and within 14 minutes, felt the pipe work connect to hot water cylinder heat picking up and gradually 25 minutes very hot. Noted the display on the boiler was 35 with bar 2.4.

Not sure what the issue could be. Tried calling the valliant installer back, but still awaiting to hear back at present.

Any help / advice would greatly appreciate. Thanks a lot.

 

[Margaret T]

Margaret,

It is almost certainly a control issue and not a boiler related problem. Was the Hive system installed at the time the boiler was commissioned, or was it added later? I have seen a number of issues where Hive has been added and not wired in correctly, impacting hot water supply (or lack of it).

In my view, the fact that you can get hot water when the heating is on means that it is unlikely to be a valve problem. You have an S plan with two two port valves. To get hot water and heating together (as you describe) both valves must be opening.

My conclusion, is that the control wiring has been inadvertently changed resulting in the two control valves operating in tandem when Central Heating is called, with no operation when only Hot Water is called.

I assume that when you set the system (the boiler) to deliver hot water only the boiler does not fire up. Is that correct?

It is probably a very easy fix - one wire in the the wrong terminal.

hello, from your description above, hot water + heating there is hot water, but hot water boost on its own there is none except like warm water. Where would this terminal wire be? Thanks a lot.

 

[Brambles]

Margaret,

25 degrees C for hot water is luke warm. Hot water is 50 to 55 degreesC

 

[Burger]

So, if you boost the hot water via hive, could you not have turned down the temperature? I’m not up on hives, but I’m wondering if that has a separate temp control? How do you know it’s 25 degrees?

 

[Margaret T]

So, if you boost the hot water via hive, could you not have turned down the temperature? I’m not up on hives, but I’m wondering if that has a separate temp control? How do you know it’s 25 degrees?

Thanks CBW1982, I note on the hot water cylinder the thermostat is is pointing to 75 degrees; the hive boost shows 25 degrees. British gas came and just turned the hive switch which allows you to adjust to temperature. Will upload photos

 

[Burger]

Thanks CBW1982, I note on the hot water cylinder the thermostat is is pointing to 75 degrees; the hive boost shows 25 degrees. British gas came and just turned the hive switch which allows you to adjust to temperature. Will upload photos

Cylinder stat should be between 60 and 65, anything more and there’s a risk of scalding and scale starts being produced.

 

[Margaret T]

Cylinder stat should be between 60 and 65, anything more and there’s a risk of scalding and scale starts being produced.

Thanks for that, not sure if the installer or British gas turned the cylinder thermostat back up as the very first time when installed it was set at 55 but now looking at the other set of photos it is showing 70?!

Everything was working fine between September 2018 - December 2018. Problems only started to occur from January 2019 when heating switched off.

 

[Burger]

Thanks for that, not sure if the installer or British gas turned the cylinder thermostat back up as the very first time when installed it was set at 55 but now looking at the other set of photos it is showing 70?!

Everything was working fine between September 2018 - December 2018. Problems only started to occur from January 2019 when heating switched off.

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Have you tried just turning the dial up when in hot water?

 

[Margaret T]

Have you tried just turning the dial up when in hot water?

I will try this and let you know. Thanks a lot CBW1982.

Should the hot water cylinder be adjusted back to 55 as per the first set up? I never touched this and noticed the changed after.

 

[Burger]

I will try this and let you know. Thanks a lot CBW1982.

Should the hot water cylinder be adjusted back to 55 as per the first set up? I never touched this and noticed the changed after.

I wouldn’t set it to 55, as it can still promote bacteria growth, 60 is probably your best bet (kills the bacteria)