PRV Problem.

[NGServices]

Hi, first post here - I have often browsed the forums and you guys seems to definitely know your stuff so I'm hoping a few of you could help me out.

I currently have a customer with Two Potterton Promax 28kw boilers heating a 20 radiator system. The rads and hw work fine; the problem I've found here is that the PRV valves from the boilers are in speedfit pipe and terminate into buckets below the boiler :-/. Now the simple solution is put them in copper and straight through the external wall, but the problem here is ALL of the external walls are on a public walk way, so if the prv was to blow somebody could be burnt, soaked or slip on ice if its cold out.

There's a sink waste around 15 meters away, I'm not sure of I can put it in there with it obviously being plastic waste, the distance it is away from the boiler and I would have to run the prv up into a false ceiling first.

I've also considered putting an external prv on closer to the sink waste, but I still have the problem of the two prv's on the boilers.

Any advice or recommendations on how to get around this problem would be greatly appreciated.

 

[davebgas]

Metallic to outside.

So what if its cold outside... That stuff that falls from the sky can freeze as well causing ice...

So long as its terminated so not to discharge onto occupants or electrical equipment it will meet standards.

 

[NGServices]

Thanks for the reply Dave.

I just thought I'd read somewhere that a PRV can't terminate on a public highway even when turned back to the wall. But I wasn't completely sure, so thanks!

 

[davebgas]

If in any doubt, check with building control, but if memory serves there in nothing in building regs to say so... have a look at Approved document G

 

[NGServices]

Just had a look through the hot water discharge section, seems like no problem atall. Going to use a prv cowl as its too high to reach without scaffolding.

Thanks a bundle!

 

[davebgas]

FYI, BS6798 says;

the location and method of fitting the pressure relief valve shall be such that:
a) the discharge pipe for water or steam from the valve is metallic and falls throughout its length; and
b) the discharge is visible and will not discharge on to the occupants of the premises or on to any electrical components or wiring.

No mention of public highway, hence to check ok with building regs etc