Need altered or ok to leave this ?

[JTplumbingservices]

So I came across an Ariston 10l water heater earlier.
I noticed the D2 pipework has a bend around 100mm down from the tundish and the 3bar comes off the end of a tee of which the branch enters the heater rather than that tee being an elbow and the 3 bar tee’d off the pipe before it.
My boss said just leave it it’ll be fine.
Thoughts ?

 

[chris watkins]

Is the safety valve a T&P or just pressure relief ?
From your description & the fact it is only a 10L unit it is more than likely an expansion relief.

 

[JTplumbingservices]

Is the safety valve a T&P or just pressure relief ?
From your description & the fact it is only a 10L unit it is more than likely an expansion relief.

It’s just a PRV

 

[chris watkins]

Although it would be nice to have the 300mm to the first bend there is no requirement as this applies to a tun-dish with a Temperature discharge. This is because a lot of water has to be pasted through the heater (well not a 10L) to reduce the internal temperature & this would back up & splash out.
All you would get from a PRV is a dribble which would be enough to reduce the pressure.

 

[chris watkins]

Not sure what you mean about the tee can you explain a bit more what you think was wrong with it?

 

[JTplumbingservices]

Although it would be nice to have the 300mm to the first bend there is no requirement as this applies to a tun-dish with a Temperature discharge. This is because a lot of water has to be pasted through the heater (well not a 10L) to reduce the internal temperature & this would back up & splash out.
All you would get from a PRV is a dribble which would be enough to reduce the pressure.

Yeah I didn’t see it causing any issues but I knew it wasn’t rite so I found the manual online and that says still to have the 300mm, and it has a line diagram with controls showing the PRV tee’d into the main before the last elbow rather than the last elbow being a tee with the valve off that.
Just wanted some second opinions.

 

[JTplumbingservices]

Not sure what you mean about the tee can you explain a bit more what you think was wrong with it?

Rite so imagine the cold main rising vertically with an elbow taking it into the heater, replace that elbow with a tee and there is a stub of pipe coming out the end of it with the PRV on there

 

[chris watkins]

This is the difference between understanding the principles & slavishly following instructions & I am glade you are interested enough to follow it up JT.

Pressure is uniform across the pipework system so as long as there are no valve in between the source of expansion & the safety valve in theory it could be placed anywhere.

 

[JTplumbingservices]

This is the difference between understanding the principles & slavishly following instructions & glade you are interested enough to follow it up JT.

Pressure is uniform across the pipework system so as long as there are no valve in between the source of expansion & the safety valve in theory it could be placed anywhere.

I agree, although if it was my job I’d have done it how the MI states.. I prob wouldn’t even have looked twice at the Prv if I didn’t look up the manual to confirm about the D2 pipe and see the diagram