Help me stop this darn water please.

[AverageDIYerEssex]

Hi all. So I am starting my new bathroom project and I've had this issue before but never sought help.

I have a Potterton Powermax HE and I am trying to find a way to turn the water off effectively to do various works. I turn my stop cock off in the kitchen and the cold stops almost instantly with the taps all open. But the hot just keeps coming out, albeit after a while it is only a trickle... but it's just been trickling for two hours and doesn't show any sign of stopping. I'm doing works upstairs and have opened all the taps in the house and strangely the downstairs taps don't run, only the top!! I thought gravity would pull it down instead of push it up!

The pipes run through the middle of the house in the joists. I can only see one shut off valve in the boiler cupboard (outside of the cover) with a red handle which I think ends up at the D.W.H cold water inlet. The pipe comes out of the floor > shut off valve > splits down (back into the joists) and up to the expansion tank where it does a loop thing and goes back down to the DWH Cold Inlet. I have tried turning this off also thinking it might stop it but nope.

I would have thought there would have been a shut off valve directly after the DWH Hot OUT that would cut any hot water coming out the system but there isn't.

Can anyone help me please as it's so frustrating as I will need to be turning it off and on a few times whilst I do this project.

Thanks in advance.

 

[dilalio]

Bung the tank and put lever valves on the outlets.

 

[Wayners]

Yeah. Make or buy a tank bung

 

[AverageDIYerEssex]

It's not vented system with a tank in the loft, it's an unvented. Is there any issues with putting a full bore shut off valve directly after the DWH Outlet from the boiler?

 

[JohnD]

Look for the outside stopcock. It will probably be next to where the front gate used to be when the house was built.

How old is the house?

Is there a hot water cylinder?

Show us a photo of the stop cock you are using, and the pipework around your boiler and of the expansion tank you mention.

What do you mean when you say "unvented?"

 

[dilalio]

It's not vented system with a tank in the loft, it's an unvented. Is there any issues with putting a full bore shut off valve directly after the DWH Outlet from the boiler?

OK, confused as you mentioned header tank.

What brand UV is it? Do you have an external expansion vessel or an internal bubble?

 

[AverageDIYerEssex]

OK, confused as you mentioned header tank.

What brand UV is it? Do you have an external expansion vessel or an internal bubble?

I can't see where I wrote about a header tank. If I did it was a mistake sorry.

It is an external expansion vessel next to the Potterton powermax HE.

 

[Wayners]

Turn water off and turn power to boiler off and water should shut off then.
Even with a trickle just cut pipes to bathroom and fit isolation valve.

Use a cheapo wet and dry vac for water while doing it

 

[dilalio]

I can't see where I wrote about a header tank. If I did it was a mistake sorry.

It is an external expansion vessel next to the Potterton powermax HE.

Can you send a few pics?
Is the expansion vessel a white/blue one or red?

If its the potable EV for the UV then it could well need regenerating and is what's causing your hot water to continue to flow.

You really need to have someone with G3 ticket to have a look/service this.

Knock it with your knuckles, it should sound hollow, if it's a dull thud then needs recharging.

 

[dilalio]

up to the expansion tank where it does a loop thing

I can't see where I wrote about a header tank. If I did it was a mistake sorry.

OK, you said expansion tank but meant vessel

 

[AverageDIYerEssex]

Can you send a few pics?
Is the expansion vessel a white/blue one or red?

If its the potable EV for the UV then it could well need regenerating and is what's causing your hot water to continue to flow.

You really need to have someone with G3 ticket to have a look/service this.

Knock it with your knuckles, it should sound hollow, if it's a dull thud then needs recharging.

It is like a white/cream colour. It's have just measured the pressure (with water all back on) and is 29.6 psi if that means anything to anyone. I wouldn't say it sounds hollow but similarly it doesn't sound too dull. I'll add some pics shortly as I'll edit them now to explain.

 

[AverageDIYerEssex]

Turn water off and turn power to boiler off and water should shut off then.
Even with a trickle just cut pipes to bathroom and fit isolation valve.

Use a cheapo wet and dry vac for water while doing it

I got a wet n dry vac so that's good. And of course a good old 'handy folding bucket'.

The issue I've got with isolators is I only have access to each utility so would have to put isos on everything as and when I get to replace each. Would it be acceptable to put a 22mm full bore ball valve directly after the boiler DHW outlet before it disappears into the floor cavity and disperses around the house? That way I know everything is isolated from one valve?

 

[AverageDIYerEssex]

Here's the setup.

I am assuming that the "cold feed in" and "cold feed to house" is the right way round, otherwise there would be no isolation of the cold feed to the boiler.

 

[dilalio]

It is like a white/cream colour. It's have just measured the pressure (with water all back on) and is 29.6 psi if that means anything to anyone. I wouldn't say it sounds hollow but similarly it doesn't sound too dull. I'll add some pics shortly as I'll edit them now to explain.

UV EV usually 3bar when open to atmosphere. When water pressure is against the diaphragm it skews the reading.

 

[dilalio]

Here's the setup.

I am assuming that the "cold feed in" and "cold feed to house" is the right way round, otherwise there would be no isolation of the cold feed to the boiler.

So you have a pipe from the EV going into your boiler?
I can't picture the setup but seems wrong as how you've annotated it!

Normally, you'd have cold mains going into a combination valve which would balance the pressure to the hot and cold feeds to the house. Then, on the hot side from the combi valve (which goes to feed the cylinder) you have the expansion vessel.

Is this supplying hot water to a combi?
Confused.com

Can you do a system sketch as those photos don't really add up!