Combi Boiler Leak - How to isolate without shutting off water totally?

[Obiwanquinnobi]

Hi wondering if someone can quickly help?

My Dad just called to say his Combi boiler is leaking water from the inside. I arrived on site and it looks like a seal or something has popped inside - not taking the cover off the boiler to check but I've done the following:

• I've shut off the mains at the stop c*ck and I also in a blind panic turned off the taps which are part of the filling loop at the base of the boiler where all the pipes are (I think its the filling loop)
  
  
• I've turned off power to the boiler etc.

This is a council house (My Dads) and they (Council) have said they will try to get someone out ASAP but it might not be today as they have a massive backlog (Short staffed more like).

In the meanwhile, I want to turn on the water to the rest of the house so Dad can have shower (Electric Shower) and get water to boil kettle for hot drinks etc. Can I isolate the boiler from the whole water main by turning the screws on the pipes that feed into the boiler whilst we wait for a plumber to come and fix the issue?

I'd attach a picture but I'm at work at present.


Cheers for any responses guys.

John

 

[durhamplumber]

I've shut off the mains at the stop c*ck ....
Rofl.
Is that deliberate or the auto correct???????

 

[Obiwanquinnobi]

Deliberate mate. Didn't know if the filters would pick it up or not

Can you help?

 

[durhamplumber]

It depends if the leak is on the central heating or mains water side .turning stop tap off will stop the leak...but will take longer if on c/h side as it will reduce the pressure to zero first

 

[Obiwanquinnobi]

I'm not sure of that. It was cold water that was coming out of the boiler if that's any help?

 

[Mottie]

If it’s a leak from the combi, just shut it off from the filling loop. You can then leave the mains on for the rest of the house.

 

[Obiwanquinnobi]

If it’s a leak from the combi, just shut it off from the filling loop. You can then leave the mains on for the rest of the house.

I have isolated it from the filling loop (turned the taps off at both sides of the loop) and also turned off the stop tap. I did both whilst there was still residual water coming out of the boiler so not sure which action has cut the supply... probably the filling loop taps was all that was needed.

Given your info - I will put some towels underneath and try turning on the stop tap.

Thank you for your reply

 

[terryplumb]

Motman ,just doing what you suggest with the filling loop will not prevent the cold water feed to the boiler for dhw from running into the boiler .john you need to close the cold water feed to the boiler there should be an isolation valve where it meets the boiler. And also make sure the filling loop is closed as well ,as motman said .you can also close the flow and return valves ,this will isolate boiler from central heating

 

[Mottie]

Ah yes. I forgot the hot water. My mistake. I was thinking along the lines of my sealed system with an unvented cylinder. Sorry.

 

[Obiwanquinnobi]

Motman ,just doing what you suggest with the filling loop will not prevent the cold water feed to the boiler for dhw from running into the boiler .john you need to close the cold water feed to the boiler there should be an isolation valve where it meets the boiler. And also make sure the filling loop is closed as well ,as motman said .you can also close the flow and return valves ,this will isolate boiler from central heating

Thank you Terry, et al.

I'll have a go when I got off work later (In the very likely event that no-one turns up to fix it)

Cheers again everyone.

 

[Obiwanquinnobi]

Ok. I've turned off the DHW valve and turned back on the stop cock - I've drawn a circle round the valve in image 1.. The filling loop taps are isolated too.

Turned on the mains water and got some god awful hammering when I turned it on full pelt - I eased off and just turned it on so the taps were flowing. I have water now but now the pressure dial is showing as in picture 2. This doesn't look right!!


Anyone ?

 

[Mottie]

That’s way too high. Bleed some water out of any radiator until the pressure drops down to 1. If it’s not going down, make sure the filling loop valves are shut off.

Edit: Looking at that picture, both valves are ON. Switch 'em off! When the levers are at right angles to the pipes, they are off.

 

[Obiwanquinnobi]

That’s way too high. Bleed some water out of any radiator until the pressure drops down to 1. If it’s not going down, make sure the filling loop valves are shut off.

Edit: Looking at that picture, both valves are ON. Switch 'em off! When the levers are at right angles to the pipes, they are off.

Done.

I thought I had already turned the filling loop taps off!!!...Obviously they must have been already off and I turned them ON!! Pressure dropping now after I've bled some water from a RAD. Phew...

This should see us though now until the engineer gets out to look at the leak. We've got a pretty cold house at present but at least we can get showered, fill kettles, do the washing etc.

Many thanks for all your help fellas. Gentlemen the lot of you

 

[terryplumb]

Now that you are at this stage ,is there any water dripping from the boiler ? If not you can probably put central heating on. Pressure gauge on boiler should be 1 bar only..........edit ,as long as you have NOT turned off the isolators on the flow and return , as I advised you to earlier. If you have turned them off don't run the boiler.

 

[Mottie]

The reason I knew that was my mum got me round because her heating wasn’t working and water was dripping out of the overflow pipe. Turned out that only one of the valves had been ever been shut off. That was under the sink and she must have knocked it open slightly when she put some saucepans under there because her pressure was off the scale too. Shutting both valves off fully and releasing the pressure did the trick.