Problem with rising main tap connections

[rsk289]

Our old mains water tap seized, so we had it replaced a couple of days ago. The original was brass, connected directly to the blue supply pipe, with a smaller outlet going to a pressure control valve with a pressure gauge. The replacement is as shown in the photo.
About 40 minutes after it was fitted, the new copper pipe blew out of the pressure gauge at the joint ringed in red, luckily above the new tap. A call-out saw it replaced again, but the second plumber said the copper pipe doesn't go very far into the valve so the olive is only just held on the copper pipe.
Should it have plastic pipe into the valve for better location, or is this OK? I'm paranoid that it's going to blow off again. We need the valve as years ago high pressure blew off an underfloor plastic joint and I really don't want to do that again. What's best? Thanks!

 

[ShaunCorbs]

IF the joint is done correctly and the copper pipe is fully in and the nut is tightened to the correct tighteness it won't blow off

I would open the lever valve fully as well

 

[Watts]

IMO lever valves are much better than brass stopcocks, fit quite a lot of them now. And copper into the vlave is more than OK if its fitted properly.

 

[rsk289]

Thanks both, a bit of peace of mind's always helpful. We're needing a Megaflo service so I'll ask our independent guy to replace the PRV at some stage as it appears to have seized too. Hopefully he can re-orientate the new one so I can open the lever valve fully!

 

[Watts]

Also there should be a double check valve fitted between the lever valve and the drain cock

 

[ShaunCorbs]

Also there should be a double check valve fitted between the lever valve and the drain cock

reason why?

 

[Watts]

reason why?

Incoming main needs a protection against backflow

 

[ShaunCorbs]

Incoming main needs a protection against backflow

back flow of what if it has all the correct air gaps etc

 

[Watts]

back flow of what if it has all the correct air gaps etc

Well yes if there is backflow prevention and every point of use then not necessary. I was always taught to fit one on incoming main and have carried that on.

 

[Stigster]

That is not a requirement though. All backflow prevention is at point of use so rarely is there a need for "whole site" backflow prevention on the main. Not to say that fitting one after the stopcock is actually wrong though.

To the OP, as long as that is all tightened and installed correctly it'll be fine. You don't need to get anyone back to install a check valve but it would be good if a plumber could turn the lever valve around a bit so it can open all the way at some point in future.

 

[Michael1960]

Also there should be a double check valve fitted between the lever valve and the drain cock

I think the Strom valve has non return built in.

 

[Ric2013]

A call-out saw it replaced again, but the second plumber said the copper pipe doesn't go very far into the valve so the olive is only just held on the copper pipe.View attachment 33652

I hope he means the previous plumber had cut that little bit of copper pipe too short and the 2nd plumber has now fitted a new slightly longer piece that fits as far into the joint as it will go, and not that the pipe is still too short really. I'm worried, though, that he means the latter. Copper into that joint should be F.A.B., if installed properly.

 

[johnduffell]

Even if you put a dcv on the incoming to protect the public main, you'd still need to protect your kitchen tap drinking water from any hose pipes, bidet/shower hoses etc.

 

[Ric2013]

Even if you put a dcv on the incoming to protect the public main, you'd still need to protect your kitchen tap drinking water from any hose pipes, bidet/shower hoses etc.

Correct. I'm assuming what you mean is that the need to protect your drinking water is another good reason to ensure hose pipes are installed correctly (with a double check valve), and bidet/shower installations are correctly carried out, in accordance with the water regs.

The one I think many people miss is the single check valve for a washing machine tap. Not needed if hoses are WRAS approved and the machine itself incorporates an air gap, but if you have, say, a Bush machine with Homebargains hoses, a check valve on the supply to it would be a good idea, and would do no harm even if a Miele were later fitted.

 

[johnduffell]

The one I think many people miss is the single check valve for a washing machine tap. Not needed if hoses are WRAS approved and the machine itself incorporates an air gap, but if you have, say, a Bush machine with Homebargains hoses, a check valve on the supply to it would be a good idea, and would do no harm even if a Miele were later fitted.

Interestingly our Miele Wda110 was supplied with a single check valve. So they clearly think the regs apply.

 

[Ric2013]

That is interesting.