Leaking Water/Heating switch in Airing Cupboard

[mattb75]

This is my first post so apologies if this subject has been picked up before.

I've recently moved to a new property (around 5 yrs old) and have a full Central Heating system with Hot water cylinder.



I noticed a watermark in the airing cupboard which had long dried out.

Over the past month there has been a tiny drop of water coming out from a switching unit from the water pump. You should be able to see some water around the nut underneath the unit in this picture.



In typical fashion I put a bowl underneath to collect the drops. However this morning the bowl had overflowed and caused the ceiling underneath to discolour and drip water onto the floor. So I guess it's now time to do something about it

The thing is there doesn't seem to be any way to isolate this switching unit from the rest of the system. There is a stop-cock without a handle above the pump which I can close off, but the feeds to the Hot water cylinder (left off the switch) and I guess to the heating system (right off the switch) have no stop-cocks.

I've never dealt with a full Central Heating system before, but I've reasonably DIY aware and don't particularly want to pay a plumber to come and charge me £100 labour to change the unit.

Any thoughts?

 

[Paul Barker]

Usually the leak is from above where you see the water. At first glance the compression nut on the feed pipe going up into the mid position valve may just need nipping up (support brass body with large water pump pliers and tighten up nut with 12 inch Bahco shifter or footprint 9's). However it is more likely that the valve itself is now leaking at the top under the plastic body of the motor unit. This means you will have to isolate heating, tie up the float valve in the feed/expansion tank, drain down the heating below this level, change valve for a new one, for which you can reuse the existing nut and olives but may need to cut down the pipe if using a fitting of different manufacture. Copy the wiring and invite trhe local council round to inspect and test your electrical work. Refill systemn deal with airlocks check for leaks replace inhibitor, relight boiler make sure all rads get warm and are well balanced.

Piece of cake.

 

[mattb75]

Cheers Paul, you make it sound so simple

I'll try the tightening up method first - My adjustable spanners wouldn't go wide enough so it's another trip to the local DIY place! If I do need to change the unit do I need to get the council around to check the wiring? - I thought under the Part P regs you were allowed to do like-for-like replacements?

Thanks again,
Matt

 

[Gasguru]

You won't need to touch the wiring - remove the actuator head, its almost certainly leaking on the spindle.

Either buy another valve body (and just use the internals) or buy a repair kit. Unless the valve body is very worn inside just leave it in place and replace the top plate and shoes.

See http://www.sunvic.co.uk/ps.html top picture

Carefully note the position of the springs (the right way round) and the shoes (the right way up)

The valve body is the same as the Danfoss - ie they always leak.

 

[Paul Barker]

As to the part p situation, despite the fact that i am part P qualified, I don't bloody know when you need the qualification or not, the red tape is so thick I just got the qualification anyway. Corgi implied we couldn't even put a plug on without it, so i got scared and took the expensive training and test equipment route. Once I got on the ocurse at an electrician's traiuning centre not an acs centre where the trainer was one step ahead of you in the onsite guide, it seemed that a lot of fuss had been made by corgi about nothing.

Anyhow I'm covered, but I haven't a clue what you can do.

 

[Paul Barker]

Anyhow, completely off topic, I did a survey of gas and plumbing for a future purchaser, including the rectification work after she bought the place, my total bill to survey clear an air lock, lkight a back boiler, puty in the required bventilation remove and cap off a wall heater and fit a customer's own gas fire was £164.

She had an electrician to survey (test and inspect?) the electrical installation, he spent no more time in the place than I did, didn't renew anything or correct anything, she only asked him for an estimate anyway. She was horrified to get a bill, though she only asked for an estimate, for over £400.

So I am seriously considering upgrading my EAL level II qualifiocation to "Big Brown Book" and then going on to do full inspection and testing. Then combined with my WRAS my Unvented cert, my Part L qualification my Corgi for part J and my new electrical test and inspect qualification, tout myself to the estated agents and get off the tools! Well 400 quid a throw for a whole house electrical tyest and inspection with no remedial work done!

 

[Gasguru]

Only one problem Paul you sound like you may have a conscience like me - and thats not a good idea if you're working with estate agents.

These people are born different to most society - everything you read and hear about them is true, they are the scum of the earth.

I used to work for several - to get the work they like you to issue bent CP12's etc. Some will expect a good sized bung for putting work your way.

As we all know there are plenty of engineers willing to cut corners/bend the rules and they will happily undercut you. Estate agents win by sticking on a sizeable mark-up so the buyer/landlord stills pays the same, they just have worthless certificates.