No heating, damp loft and water pooling!

[1littleoyster]

Hello,

I've recently bought a house with quite an old CH system. The boiler is a Thorne Olympic so possibly 30+ years old (house built 1974). The system was okay, but the radiators weren't getting hot enough, so a plumber fitted 2 new rads in the lounge/diner and one in the hall. Apart from some balancing problems, all new rads have heated up okay and the bedroom rads continued to work fine.

This weekend I spotted some brown patches on the ceiling in the lounge directly under the bathroom and airing cupboard. There was quite a lot of water under the floor boards which I have mopped up and mostly dried with a hair dryer. There doesn't appear to be a leak from any of the pipework running under the boards and the damp area seems to be contained under the bathroom/airing cupboard space. When the boiler fired up, water trickled down from a pipe coming from under the airing cupboard/hot water tank.

Also, the CH would not come on even when the thermostat was set to 25C. The boiler was firing up, but the rads not coming on. (still plenty of hot water though) We suspect that the valve for the CH is not working as the pipes are getting hot before the valve but remain cool after it. We think any warmth after it is only conducted, not from the water flow.

Also (!), the loft is very damp. There is a pipe that comes up from the airing cupboard taking hot water into the loft. This pipe doesn't go into a tank and isn't capped off, it just ends leaving it exposed and we have a feeling that it is the hot water from this pipe creating steam and condensing in the cool loft that is creating the excess moisture. That sounds quite obvious, but I have no knowledge of CH systems, so if I see an exposed pipe, i trust that thats how it should be!

But should the pipe be carried out through the loft to redirect any steam and avoid creating excess condensation traveling back down the pipe after an burst of steam?
And might the possibly broken CH valve be causing all the heat from the boiler to go into hot water, creating an excess, travelling up the pipe to create more steam and condense down the pipe and settle under the floor boards?

I know this sounds like I'm trying to answer my own question, but i really would appreciate any advice offered.

If the pipe shouldn't be left exposed in the loft and should be re-direct outside, can I do that job myself, or is it a professional job?

Thank you.

 

[75pete]

Sounds like the pipe in the loft is the vent / expansion that should vent into the small tank in the loft.

Do you have a small tank in the loft?

This small tank [ header ] supplies water to keep the CH topped-up. There should also be an over flow pipe from the header tank to the out side of the house.

The rads not getting hot points to the system in need of a flush or other problems ie pump / air in system etc

Adding more rads would not make others hot.

Your feeling about the valve sound possible.

 

[1littleoyster]

There are two tanks, a small square one above the hot water cylinder and a larger lidless cylindrical one.

There were two 22mm copper pipes going up into the loft space. One of them was making gurgling noises and was open-ended, the other was the one the water was dripping off/out of. It was covered in silver lagging and was directed into the cylindrical tank. I think that was the one that was getting very hot.

There was a grey plastic overflow pipe from the small square tank to outside, I think.

 

[TonyW2]

Try manually setting the valve open to see if rads then get a flow and your problems cease.. This sounds a likely culprit.

I take it you mean the plumber replaced two rads, not fitted two additional ones?

Your "open" pipes sound like the normal arrangement; the one into the large tank is for expansion/vent from the domestic hot water and the one into the small tank is for the boiler heating water.
Please check that the hot water you say is coming from the "open" vent/expansion pipe is into the small expansion tank, (and not as you state.--this would better fit with your symptons).

You say there is a pipe that sometimes has water running down from it; trace the source of this leak.

 

[1littleoyster]

TonyW2 -

Hi. The pipes did get hot when the valve was manually opened. Can I buy the motor part of the Honeywell valve separately, or does it come only as a whole part?

Yes, the plumber replaced 2 rads in the lounge and the 1 in the hall.

The open-ended pipe doesn't go into the small tank. It just points up and the other pipe goes down through the airing cupboard and under the boards.

Thanks.

 

[75pete]

Have a look at FAQ number 3.........valves

 

[TonyW2]

That pipe should be "benT over to discharge back into the expansion tank. But don't just bend it! Simple DIY should sort that one.

Regarding the water running down the pipe that you mention--Have you traced this to its source whilst it is running? This needs rectifying. (It may be that it is the same expansion pipedischarging over its own outer surface.)
Valves-as manually setting the valve caused the radiator flow to start up and run normally, it seems like the valve is faulty and you should be able to remove the head unit and get replacement seperately, but unfortunately, it may also be the main part of the valve that is sticking, so you will need to investigate a bit more. It may even be the valve area that is leaking and dripping. Hence why tracking it down is essential.
(Try your plumbers merchant and ask for a deal on this valve--BQ etc can be pricier than necesssary) If you have to change the whole valve, you are into draining down etc.

 

[1littleoyster]

75pete - Thanks for the FAQ, I've printed it off so shall have a look this evening.

TonyW2 - So its possible that the open pipe needs another bit of pipe to take it to the (larger) expansion tank?

As far as tracing the source of the drip goes, all i have is a newspaper on a container under the floorboards, below where the little gush came from last time (I hope). The only pipes in that area are the ones in the airing cupboard which have a slow, less than trickle of water coming down them. But I guess this has built up over the weeks. So it could be condensation, a leak or an overflow. The last gush of action I saw was when the boiler kicked in. Maybe it is an over flow.

I'm a bit confused, so I think I need to spend a bit more time looking at it really and perhaps drawing a diagram!

Thank you both for your help - much appreciated.

 

[TonyW2]

Yes it will need a bit more pipe, but it should discharge over the central heating tank, and this would normally be the small one.
Do make sure, as you don't want central heating water going back into your domestic water supply tank.
A diagram would make it clearer as to exactly which pipes are involved.
The absence of any overflow escape for the c/h header/ex[pansion does need sorting out or you will have a serious problem if it suffers from an inlet supply valve failure and the hot water "overflow" still needs rectifying. This may be that the pump needs turning down.