HELP: Pressurised/Unvented cylinder - No hot water, central heating works fine

[KingK]

Problem: No hot water from unvented cylinder, although central heating works fine.

Hi All - apologies for the lengthy post but I'm keen to get across as much detail as possible.

I'm a novice, any advise would be really appreciated.

Setup:
Pressurised/unvented cylinder (Tempest)
System Boiler (Worcester)
2 x 2 port motorised Honeywell valves
Nest smart control

General info:
Installed 3 months ago (previously gravity fed) - no problems since now.
Water softener installed 2 months ago - no problems until now.
When turning on HW from the app I can hear the click from the HeatLink.
HW temp set to around 63 degrees, pressure gauge indicated being at 1.5.

Scenario 1:
Turn on HW from the nest app.
- HW icon says ‘on’ but does not go orange as it usually would.
- Boiler does not “fire” up i.e. the green light doesn’t flick on.
- HW 2 port valve stays in the ‘closed’ position i.e. there is resistance when trying to turn it to the manual override function.

= No HW.


The above would suggest a problem with the HW 2-port valve.

However, when I turn the valve to the override ‘on’ position, the boiler still doesn't fire up and still get no hot water.

This suggests a problem with the boiler.


Scenario 2:
I turn on both HW and CH from the HeatLink manual control panel.
- Both icons in the app go orange (as you would expect).
- Boiler fires up, light goes green.
- 2 port valve for CH frees up, HW stays in the closed position.

= CH comes on, but no HW.


Again, this suggests a problem with the HW 2-port valve.

However this is where things get strange:

Following on from Scenario 2:

- I now place the 2-port HW valve in the override position
= I get HW.
- I leave it like this for 10/15 minutes (both HW and CH are on and working).
- Turn both HW and CH off from the HeatLink.
- Take the HW 2-port valve out of the override position.

Now, when I turn on HW from the nest app
= Everything works perfectly; boiler fires up, HW 2-port valve works (gear becomes free and can hear the gear close when turning HW off), app icon goes orange and I get hot water.

The HW now works on request for the whole day and suggests the 2-port is actually working.

So everything appears fine but then the following day I have the same problem. I have to go through Scenario 2 (plus the additional steps) to get things working for the day.

It’s almost like the system needs the initial ‘boost’ from the CH to get things going.

Here's where my thinking is at:
- Upon calling for HW, the 2 port valve should open up straight away even before the boiler doesn't fire up - is this correct (seems to be the case with the CH)?

As this doesn't happen, this suggests a fault with the HW 2 port valve.

BUT why does the HW 2 port valve start working perfectly once I've given the CH an initial boost?


Daily I'm having to go through Scenario 2 (plus additional steps) to get things going for the day in the hope it just starts working like normal the following day 🙁

Any help / advise would be greatly appreciated....Thank you in advance!

 

[Rob Foster]

Wait until the collective wisdom has woken up - its b/h Sunday after all Sounds like a control issue and I cant help you but there are some clever buggers on here

 

[ShaunCorbs]

If it's only 3 month old get the installer back

 

[Scott_D]

Any pictures of the setup?

 

[KingK]

Unfortunately, the installer is non-responsive so he wont be back to sort it out.

Images attached,

Thanks

 

[bacon_sandwich]

You are going to need a voltage tester to make sure 240V is getting the the valve when it should, it could simply be a loose connection or an intermittent motor fault on the valve, without a tester you will be guessing

 

[ShaunCorbs]

not very good install non of the safety pipes are installed

best get a g3 and gas safe engy to have a look over the system

 

[Chalked]

Hi
As an easy option.
Unscrew the the black plastic cap on the thermostat, at the bottom of the cylinder. Under that is a thermal reset. Try pushing it in. If that works, good, if not, it’s time for a g3 installer I’m afraid.

 

[KingK]

Thanks guys, appreciate the input.

The installer was Gas Safe registered, so disappointed he hasn't installed the safety pipes...please can you tell me what safety pipes he hasn't installed? I will call him again and try one last time to get him round.

Also, am I able to report him to Gas Safe or something for not installing these, I'm guessing it's fairly serious breach?

 

[Scott_D]

Any pictures of the boiler and flue?
You can request a gas safe inspection.

 

[bacon_sandwich]

TBH, i cannot really see much from the pics, dont appear to be able to blow them up. the PRV, (red thing near the big logo) should go somewhere so pics of that would be useful. Cannot see Gassafe being interested in a faulty cylinder install but if the guy cannot install a cylinder its possible he cannot install a boiler

 

[KingK]

Thanks, I've uploaded some more photos...

 

[Scott_D]

I looks like a dozen different people have fitted bits and made alterations with what ever materials they had lying around.
What's the story? new boiler and cylinder onto existing pipes?
Same person fitted the softener?

 

[KingK]

You're quite right:

When I moved in there was a gravity fed system in the loft.

The new installer removed all the old stuff in the loft and fitted this cylinder using the same system boiler (he had to move the boiler up to accommodate the new cylinder though).

The water softener was fitted by Harvey's, who supplied the softener.

 

[chris watkins]

Hi KingK
As the safety valves do not discharge to a safe place you are going to have water leaking into that cupboard at some point.
If this occurs under fault conditions this could be dangerous as the water could be very hot, for this reason -
The requirements for the installation of these hot water cylinders fall under the Building Regulations (Approved Document Part G) it is classed as a "notifiable installation" and you as the house owner are required to notify it to your local Building Control Office.
If you had employed an installer who was a member of a competent persons scheme they could have self certified the installation to B.C. for you, you would have received confirmation through the post shortly after the installation was completed.
Gas Safe do run a Competent Persons scheme for the installation of these but you need to check that they had joined that part (not just the gas), if they have, you can ask them to investigate.

Unfortunately it is your responsibility even though you commissioned them to carry out the work for you.

You need get a Part G registered person to check and then correct the installation, they can also have a look at the Nest controls which are not working correctly at the same time.

 

[townfanjon]

Haven’t read all the comments, bloody shocking install

 

[KingK]

The plumber said he would self certify given he is a member of the competent person scheme under Gas Safe.

Having said that I've not received any paperwork since the install (in May) and have chased him since (said he would look into it). I've just checked on the Gas Safe website and it doesn't look like he's registered it.

So where do I stand? Can I complain to Gas Safe for (1) the safety valves not being connected and (2) The install not being registered?

Or are these now my problem to solve?
Having already given him thousands of pounds, I'm obviously disappointed. How much do you think it will cost to get these safety valves on?

 

[ShaunCorbs]

is he gas safe / have you checked on there ?

 

[KingK]

Yes, he's gas safe (I check him out on Gas Safe website before he started).

I couldn't find him on there today, so got a friend to call up as a new customer to check he was registered. He said he's renewing his membership and will be back on the website on Tuesday, as he's not been able to renew due to the bank holiday.

Let's see - I will post his ID number once it's active.

 

[chris watkins]

The plumber said he would self certify given he is a member of the competent person scheme under Gas Safe. - Have you that in writing ?
Having said that I've not received any paperwork since the install (in May) and have chased him since (said he would look into it). I've just checked on the Gas Safe website and it doesn't look like he's registered it. - For Gas ?
So where do I stand? Can I complain to Gas Safe for (1) the safety valves not being connected and (2) The install not being registered?
Gas Safe if he is not Registered for gas work & he moved the boiler.
See below for the unvented.
Or are these now my problem to solve? - Yours as you are the owner I am afraid.
Having already given him thousands of pounds, I'm obviously disappointed. How much do you think it will cost to get these safety valves on?- Did you not hold any money back as a retention until you got it competed & the paperwork ?
Not possible to say without seeing the route for the wastes & knowing your local BC charges for inspection

In the first place put it in write to him stating that the installation is not complete as the safety valve discharge wastes have not been installed.
Ask him to respond state that you need a response by ?? (a least a week or two) otherwise you will have no other option than to take this further.
So was he registered to carry out the gas work at the time he moved the boiler ?
If he was on the Gas Safe register then you should be able to check that he has joined their competent person scheme for hot water systems (often called un-vented / partG).