Is this horizontal Tank Installation correct?

[endecotp]

Would you mind listing the deviations you saw

I’m looking at this document; it’s not entirely clear if it’s the right one:

https://ukcylinders.co.uk/wp-content/uploads/2024/06/UK-Cylinders-Indirect-Horizontal-External-Expansion-Manual-V1-2024.pdf

Hmm, it seems I can’t copy-and-paste from it but here are some approx quotes and other notes. (To re-iterate, I’m no expert.)

“The orientation of the cylinder must have all key connections …. uppermost”

“Connection to expansion vessel” (pointing to a port on the inlet monobloc that is not used on yours)

“Mount the expansion vessel … above the cylinder”

Your balanced cold connection is not used (do you have a pressure reducing valve on the cold supply elsewhere?)

I cannot see a tundish. Where does the pressure relief pipe go?

 

[baldbob]

G3 registered = Registered under G3 of the building regulations Part G

MI = Manufacturers Instructions

UV = Unvented

Thanks CountryFan!

 

[Razor900]

First things first turn both thermostats down by a quarter turn and let the cylinder come down to temp with normal use over a day before checking whether the water is still hot enough for you.

That's a crap install and you definitely need to get someone who knows what they are doing to look at it but you don't need a cylinder full of scalding water at the top of the house with potentially incorrect discharge pipework so do the stats first please

 

[Johntheo5]

Thanks John, all updated in the original post - hopefully that helps!?

That very strange orientation will probably affect the immersion/stats as the elements are designed to be horizontal, since you are familiar with electrics it should be very easy to check with a multimeter if/when the stats are switching, even turning them up/down should result in a audible click, I though I saw somewhere the cylinder test pressure was carried out in 2006 but can;t see it now, you'r expansion vessel date of 2025 suggests its a pretty new install, so maybe only behaving like this since the mains temperature has risen in the past few weeks??, still, a compromise stat(s) settings should prevent the T&PRV lifting at a presumed 95C, those simple tests should tell you if the stats are OK.

 

[Razor900]

I though I saw somewhere the cylinder test pressure was carried out in 2006 but can;t see it now

The cylinder was manufactured in December 2025 according to the label

 

[Madrab]

+1 re water too hot - get the stats turned down, looks like they could be set to max.

I think the trouble here is that the Manu Instruction for the unit seems to be elusive - under the model WWAH250L - there doesn't seem to be much apart from a world heating reference. You should have been given the manual for it? Can you post a pic of the front page, does it have the manufacturers name and model of the unit?

As others have said, that does not look like a good install, it doesn't appear to adhere to some of the norms that other horizontal cylinders would normally follow.

The installer needs to confirm that they are G3 (HWSS) certified, that the install has been benchmarked, notified to the Local Authority and registered with the manufacturer. I'd certainly get looking for a qualified and recommended engineer that is familiar with horizontal installs. OI hate them, always give problems. I don't install them, rather 2 smaller horizontal units fitted in tandem.