Unvented cylinder inspection

[Plumb Tidy]

Hi Lads/lasses just wanted some advice on unvented cylinder inspection. I just took on what seems to be a contract for a block of flats all with direct heating via immersion. The way they have been installed seems a bit off as there is no check valve on the supply to the cylinder. It goes,
Stop tap
Double Check valve
PRV
then tee's off to the cylinder feed and cold water supply for the rest of the apartment.
When draining i noticed if i opened up a cold tap downstairs and opened the TPRV hot water came out the cold tap.
I explained to the customer what's going on and she said she has noticed she has to draw off a bit of hot water out the cold tap before filling a glass of water and thought it was normal.
The cylinders haver been installed in 2004 was the water regs different then? as they didn't require a DCV?
Can i carry out a cylinder safety inspection in this current state?
I have only been doing unvented for around 6 months now so I'm still getting to grips with the certs. I have a picture but my phone won't upload as of yet.

 

[Scott_D]

What brand?
Are any manufacturers instructions available?

 

[Plumb-tidy]

No manufacturers instructions, around 250 odd apartments I have been to two so far today which are the same

 

[Ricky]

Hi Lads/lasses just wanted some advice on unvented cylinder inspection. I just took on what seems to be a contract for a block of flats all with direct heating via immersion. The way they have been installed seems a bit off as there is no check valve on the supply to the cylinder. It goes,
Stop tap
Double Check valve
PRV
then tee's off to the cylinder feed and cold water supply for the rest of the apartment.
When draining i noticed if i opened up a cold tap downstairs and opened the TPRV hot water came out the cold tap.
I explained to the customer what's going on and she said she has noticed she has to draw off a bit of hot water out the cold tap before filling a glass of water and thought it was normal.
The cylinders haver been installed in 2004 was the water regs different then? as they didn't require a DCV?
Can i carry out a cylinder safety inspection in this current state?
I have only been doing unvented for around 6 months now so I'm still getting to grips with the certs. I have a picture but my phone won't upload as of yet.

You cannot put a valve between cylinder and one of the pressure releif valves, and yes the way it is configured the water will syphon down cold if the supply to cylinderis isolated and you open TPRV.

 

[Plumb Tidy]

Cheers Ricky. Its an Albion stainless steel no fitting instructions and none on the web to be found. So as it breaches water regs because its allowing hot water to mix with potable water, legionella and all that i guess i cannot sign off the inspection report. I just wanted to know if the regs changed from 2004 till now because it looks like 250 apartments are piped up wrong?

 

[Plumb Tidy]

You can see the gate valve at the bottom of the cylinder feed a pipe goes through the floor. this is the cold feed to the kitchen and bathroom

 

[Plumb Tidy]

So when expansion is taking place it expands into the cold and then into the expansion relief valve as the expansion vessel was flat as a pancake and has not had a service since it was installed.

 

[Plumb Tidy]

Ok i got hold of kingspan that bought Albion cylinders so thanks Scott D for the hint. They have been plumbed up incorrectly as they should have a on return valve protecting the cold feed to the apartment even back in 2004. I ow have the pleasure of changing around 200+ cylinders

 

[ShaunCorbs]

I would think it’s acceptable as it’s not really different than installing the inlet block on the cold water mains and having the cylinder upstairs in the airing cupboard

you might have a check valve passing on a tap or shower ?

 

[Scott_D]

Is there an expansion vessel fitted?