Urgent unvented hot water cylinder help needed.

[Scottwood75]

I was called by a friend to have a look at his unvented cylinder. The tprv was discharging into the tundish so I went to have a look, found it like this.

I know there are a few serious errors and would like someone to help identify them all to confront the installer.

The D2 pipework is defiantly wrong and terminates by going through the brick wall into thin air, on a 3rd floor flat. also its plastic overflow pipe.

Comments and thoughts please.

 

[shorticus]

is that IV on the hws? That's a big no no!

Oh and petty I know but the pipes should be lagged

this thread just popped up again in my inbox and after re-reading it I have to humbly retract the first part of my original statement, doh!
note to oneself, never underestimate the value of double checking, "measure twice, cut once" as my old tutor used to say.
Still should be lagged though )

 

[cr0ft]

I think the advice given so far is spot on. The only thing I would add is that the installer is allowed to draw off a balanced cold supply prior to the combi valve, using a pressure reducing valve on this. Some manufacturers (Gledhill for one) recommend doing this as it increases the amount of water available to the taps (assuming the mains pressure is over the usual 3 bar working limit for these cylinders. The advantage of doing this would be if the incoming mains is at, say, 10 bars, he can have one hot supply at 3 bars, one cold supply at 3 bars and thus get the benefits of using the fullest amount of incoming pressure/flow rate possible. If that makes sense! If he's done it this way there needs to be a small potable water expansion vessel on the cold pipework after the pressure reducing valve. I doubt there is though!

All of this said, I've not even sat my course yet and I can tell that the D1 and D2 pipework is simply wrong. Any valve on the hot water outlet is wrong. As I understand it all outlets should have separate isolating valves. I believe this is to stop a vacuum situation building up in the cylinder? Maybe someone can enlighten me on this one.

 

[johnwater]

hi all,
i'm new to all this and have recently passed bpec vented and unvented, this is pure frightening to see.
the advice on here is great and very helpful. with mechanical experience, recent plumbing exams passed and a new business I hope to be a part of the change people wish to see.

regards
John

 

[spanners1967]

nice use of bends though... hardly an elbow in sight! lol

 

[nysk2008]

lovely install - think I found the plumber! Defo not got his UVHW ticket though

 

[southcoastboile]

that is shocking! ..... while on the subject, i had a boiler the other day were the prv outlet ran along and then upwards by about 500mm then out the wall and down at ground level (was in an atik), i no this is not correct but the prv would still be able to discharge and would eventualy push water up the pipe and to outside, i informed the customer that this was not correct and got the usual "its been like that for years, no one has ever said about it before" i made a note on my jobsheet as the customer wouldn't pay to have a new hole drilled and pipework altered, just wondered what you guys would do in this situation.

 

[Gray0689]

You did all you could if they don't want it fixed then that's there problem

 

[johnwater]

definitely, you're professional enough to spot the problem which could be seriously hazardous, their call if they wish to ignore this matter, and like you say it's all recorded on your job sheet which covers yourself which is the main thing!

 

[Osp]

Only just noticed this thread - should be used as a teaching exercise on the courses!

Hard to tell from the pics but haven't the electric flexes been fandangled across the doorway as trip wires in an attempt to kill anybody trying to inspect the setup?

And I wonder why the floor looks damp?