tank in the attic causing huge condensation

We have just bought a house and this is the first winter in it, I went up to the attic earlier to get the Christmas decorations and noticed that there were hundreds of droplets on the felt and everything was damp.... firstly i thought that there was a massive leak and had a good look around without finding anything.

Then I noticed a mini tank with an over flow pipe in it with a ball cock (for cold water) and a wavin pipe pouring in hot brown dirty water into it like a tap. this seems to be running up from the immersion tank and is causing all the condensation.. this is ruining everything up there and seems to have only happened in the last few days when the heating is on.

Surely this isn't normal, can anyone offer some advice?

Lewis_Benson

That's the feed and expansion tank for your heating system.

It should not be overflowing like that unless there is a problem.

You need a plumber to look at it.

https://www.boards.ie/discussion/comment/121451073#Comment_121451073

It only slightly over flows when the heating is on but the issue is the steam coming up from the tank. the brown water is close to boiling hot and has a very heavy flow

Lewis_Benson

https://www.boards.ie/discussion/comment/121451107#Comment_121451107

You have a problem with your heating system causing this.

Find a few local plumbers tomorrow and start phoning them.

https://www.boards.ie/discussion/comment/121451131#Comment_121451131

Brilliant thank for the help

10-10-20

If the house will be vacant tomorrow during the day then leave the attic hatch open to promote ventilation of the attic. The stack-effect should push the damp out the eves.

Timing belt

It could be a faulty valve or corroded pipe that is allowing pressurised water mix with un-presurised water and as a result forcing the water out the overflow…

https://www.boards.ie/discussion/comment/121451178#Comment_121451178

the water is manky brown? would that suggest either the two you've mentioned

con747

https://www.boards.ie/discussion/comment/121451213#Comment_121451213

It could be iron in the water, do you have a well system? Mine was brown until I got the well water treatment system upgraded.

https://www.boards.ie/discussion/comment/121451223#Comment_121451223

No, its a house in Dublin being fed from the mains. it could indeed be rust in the water. the amount that was pouring into the tank was quiet alarming . Was like a tap

Wearb

What's your heating source? Have you changed anything?

Maybe try turning down your circulation pump.

Timing belt

https://www.boards.ie/discussion/comment/121451213#Comment_121451213

to me it would suggest corrosion and the problem is with the boiler unfortunately

10-10-20

https://www.boards.ie/discussion/comment/121452005#Comment_121452005

The brown colour could come off the radiator steel too. I'd be suspicious of that if system has been continuously ingesting air over a period of years.

carveone

(I'm not an RGI btw so best assume i'm an idiot 😉)

This is kinda interesting and I've often wondered about systems that have been converted from F&E to your general purpose system boiler, without actually removing the F&E tank.

So, in my non-expert opinion, the feed from a heat-only boiler comes out and the vent is attached at that point. The vent arcs up and over the tank (by about 1/2 metre - not sure why but I'd say to avoid startup surges feeding the tank). After the vent attachment point, the feed is attached (within 150mm apparently) and then the pump comes after that lot.

So you come along with yer system boiler, remove the pump and install the boiler. Now the pump is before the vent/feed. This strikes me as a bad idea. Could this lead to what the OP is seeing?

In my parents' place, the RGI capped the vent and put a one way on the feed. Mainly because he wasn't arsed removing the tank and it made it easier to put fernox into the system.

Timing belt

https://www.boards.ie/discussion/comment/121452199#Comment_121452199

Well if it is the radiator water finding its way to the cold tank via the overflow in the emersion tank then you have a problem whereby the water in the coil (hot pressurised water) is mixing with water in the hot tank causing it to overflow into the cold tank via the overflow.

KildareP

Does it only overflow when the heating is on? If yes, then it's the system pumping over - either a recent blockage, or it was incorrectly piped or pump speed set too high and could well have been happening for years. Eventually it'll rot the system as you're constantly introducing oxygen to the water which can rust the system.

Or does it always overflow regardless of the heating being on? If so, then it's most likely a leak in your hot water cylinder coil back feeding the heating circuit. That's a health hazard as the flow could reverse if your mains pressure dropped (if it's a mains fed cylinder) or your cold water header tank dropped below the level of the heating system header tank (if it's gravity fed).

10-10-20

https://www.boards.ie/discussion/comment/121452308#Comment_121452308

The way I read it, it's the CH mini-tank which is doing the overflowing and not the main cold water tank.

carveone

https://www.boards.ie/discussion/comment/121452362#Comment_121452362

Ditto - it's not the immersion expansion that's overflowing (that's a whole other issue if you see that - don't ever ignore a boiling immersion!) but the vent into the F&E tank.

Perhaps get a boiler checkout* from an RGI - someone who can see your entire system and give you a sane recommendation. It'd have been better in July but, you know, here you are.

* Good to do anyway if you haven't already. I told Bord Gais in July that "boiler's vibrating a bit, is that the fan?" and they said "no, it's a cracked flue collar" and I went "Oh bugger" and they went "Yeah. It's an extra 10 euro is that ok?" and I went "Instead of CO poisoning? Seems like a deal to me."

Timing belt

https://www.boards.ie/discussion/comment/121452444#Comment_121452444

i meant F&E tank but it’s still the same issue where there's hole in the coil or a faulty valve which allows water for the central heating into the domestic hot water being stored in the cylinder which increases pressure and causes the overflow. 100% get a RGI engineer if it’s Gas but this sounds like a plumbing issue to me with a fault in the cylinder the most likely cause.

Lewis_Benson

@[Deleted User]

Did you manage to get a plumber?

Hi, sorry for the delay getting back to you all. thanks for the great suggestions.

I got a plumber and it seems like a new Expansion Vessel fixed the problem.

10-10-20

https://www.boards.ie/discussion/comment/121469075#Comment_121469075

Great news, thanks for the update!