repairable valve?

[REDSAW]

is the prv (the black bit to big brass nut) on this all in one repairable?
its dripping from the name plate and brass nut, basically the plastic!
offout now be back late, thanks

 

[macackau]

That is an older valve, don't think it is repairable and due to its age I normally go for a replacement anyway. I get mine from advancedwater.co.uk and I think it's about £120 ish. It's a different size too so you'll need to make adjustments to pipe work. I always email them a photo and they reply with a link to the part that I need.

 

[gassafe]

Would be a real pig to get out, if it's dripping there the complete internals are corroded so worth getting the complete prv replacement... I changed just the head once but it took a good 45 minutes struggling to pull the old one apart lol!

 

[ShaunCorbs]

hope thats not the expansion flex on the pressure blow off

 

[Best]

hope thats not the expansion flex on the pressure blow off

Looks like it is.

 

[SimonG]

hope thats not the expansion flex on the pressure blow off

It is. Was at one today exactly the same.

 

[macackau]

So the expansion vessel isn't actually connected then as the PRV will normally be shut the whole time!

 

[chris watkins]

hope thats not the expansion flex on the pressure blow off

Looks like it is.

It is. Was at one today exactly the same.

FYI OSO supplied a flexible hose at one time to connect the expansion relief to a tee on the discharge pipework.

 

[ShaunCorbs]

FYI OSO supplied a flexible hose at one time to connect the expansion relief to a tee on the discharge pipework. View attachment 25367

thats rubbish, and really d1 should be 22mm

 

[chris watkins]

thats rubbish, and really d1 should be 22mm

Really, care to show me where it says that in G3 ?

 

[ShaunCorbs]

Really, care to show me where it says that in G3 ?

3.52 Where a manifold is used it should be sized to accept and discharge the total
discharge from the discharge pipes connected to it.

so when they both discharge/blow that 15mm wont be able to handle it (the full flow), would be surprised tbh if the 22mm would esp if it was 9m (with bends)

 

[gassafe]

All d1s are teed in like that tho, on most unvented cylinders...

The tundish is always 15 / 22 too right?

 

[chris watkins]

3.52 Where a manifold is used it should be sized to accept and discharge the total
discharge from the discharge pipes connected to it.

so when they both discharge/blow that 15mm wont be able to handle it (the full flow), would be surprised tbh if the 22mm would esp if it was 9m (with bends)

With all due respect Shaun don't think you quite understand what happens under fault conditions.
Because of the pressure rated difference between the T&P (typically 10Bar) and the expansion relief (typically 8Bar) they don't discharge at the same time. If the T&P went off due to temperature it would run full bore that is why the the D1 must be line size & can't be reduced (as this would effect its KW rating).

"3.52 Where a manifold is used it should be sized to accept and discharge the total discharge from the discharge pipes connected to it." this refers to multiple cylinders connecting to a common "manifold" discharge pipework.

After all do you think OSO would supply something that was not suitable, all units sold have to have been tested so that they meet the standard set under BBA or KIWI

 

[SimonG]

All d1's ive seen are 15mm. All bar 1 d2 i've done have been 22mm. The other was 28 due to the distance.