I have noticed that the overflow pipe at the side of the house is doing its job and getting shut of water from the boiler which i presume must be over filling The heating is working as well as it usually does, however the presure gauge is higher than usual (the odd dripping radiator usually causes the pressure to occasionally drop) but hot water coming out of the side of the house when the heating is on is not normal We have a direct water sytem i think (there's no tank in the loft) so its not a cylinder float type problem.

Maybe 2 years ago now the same problem got me calling an engineer out, who serviced the boiler and the problem was solved and he never did tell me what was causing the leak . Is it pick the phone up and part with £50 time

Any thoughts/ ideas welcome. Thanks CP

Is it a self condensing boiler? Or standard combi?

Either way its not a good sign and an immence waste of energy

Its a combi.

make that call and get it fixed. If you don't you will get a very large bill as you are effectively having all your hot water taps running 24/7.

Not my area (I only go as far as replace ballcocks in cisterns!) but thought this might help: http://www.scoobynet.com/archive/index. ... 09022.html

Thanks for that very helpful. However I think I may need a plumber having read what probably is the root cause.

*Red knob update*

No, not talking about me have just flicked a red knob round a few times from what I think was the valve to the overflow pipe (i hope) and it appears to have stopped dripping (for now, heating on still). Im off out on the lash soon so if Cherylhoney doesnt post this evening and there are fire engines outside the house i thnk i might jhave fiddled with the wrong switch

cheers (for now)


edit1 false alarm still leaking

Oh god! Not sure I like this idea!!

I'm always wary of turning knobs and switches on boilers as last time I did it I was woken in the early hours by the boiler thumping and banging and vibrating. All I could do was unplug it. The engineer next day said the pressure had got so high the boiler was on the verge of exploding which would have done away with half the house. Apparently a safety valve had been turned off

This is emotional blackmail i'm off out on me xmas do

Jesus knobend wait until I get home FFS! You know you shouldn't mess with anything like this... I think I might know what it is.

Just given Cheryl a ring, thought i best had just in case it was the last time i'd be speaking to her anyway turns out she might have been fiddling with man switches and with her delicate touch she might not have fully closed the valve that fills the tank whenthe pressure drops. its like a bloody soap opera already this thread. More news to follow readers

FFS Cheryl, did your mum never tell you not to fiddle with men knobs?
Fiddling with men knobs causes things to explode and makes an unholy mess.

Happened with mine a couple of times. Luckily the house didn't explode, nor did the boiler.

Instead it was the plastic pipes that gave out first. Nicely at first floor level so they could drip (OK, pour) through everywhere. Shame the boiler hadn't caught fire as that would have put it out nicely.

At least you will be safe if something does go wrong

If switches and knobs were not meant to be pressed and pulled then things wouldn't have them is my view

I was going to suggest, that either your system is draining down, or excess water is entering it.

If it is the inflow that has been "tampered with", the it needs shutting off. Then making sure that you have bled all your radiators, open the drainage valve and reduce the pressure to 0.7, if cold, or 1.0 if hot.

If the inflow is OK, still bleed the rads, and manually reduce the pressure, as it may be "overflowing" due to high pressure...

I hope that this helps, and god luck.

There is a problem with my radiator in that it always needs bleeding - it needs sorting really. Because of this the pressure drops and I need to turn the tap to get the pressure back up. It's quite stiff though and it's happened before where the tap has been left on a bit so the pipe at the side of the house lets out the overflow. Any ideas why my radiator always needs bleeding? Once it's been bled it's OK for a bit and then it happens again. We've even tried bleeding all the radiators in the house.

Air must be getting into the system somewhere - probably in the bit before the radiator that needs bleeding.

I'd recommend calling a plumber or moving house.

There is a small leak somewhere, allowing air into the system. (Note, it may not be letting water out.)

There is stuff (a liquid) that you can put into it, to plug such small leaks. B&Q sell it, as do Plumbcentre etc, which will probably be cheaper than B&Q. I am not sure how you put it into a Combi system. Normally after draining a system down, you pour it into the tank, and refill the system.

Have a look at the stuff, and read the instructions before buying it!!

This looks OK.

http://www.screwfix.com/prods/37894/Plu ... STHZOSFFI#

Thanks blahblah I'll look into that. Otherwise I've got a friend who's husband is a plumber so I'll casually get back in touch with her and see if she fancies a drink.

In my last place I had an old style "direct" set up. There was a cold water tank above a hot water tank with immersion heater. Off the hot water fed from the hot water tank there was an overflow pipe that fed back into the cold water tank.

We used to occasionally hear hot water overflowing and didn't think too much of it but then one day it was flowing constatly and the cold water was flowing hot!

The thermostat on the immersion heater had failed and it was permanently running. It had begun to run anyway with itself. To relieve pressure water from the hot water tank was flowing into the cold water tank and it had reached a point where that was now hot and feeding the hot water tank.

I ended up getting a new system but be warned if it's chucking out water it might be a safety feature in the system's design to avoid over pressure.

this seems the natural place for this question;

a couple of weeks ago the central heating got cranked up for the first time in months.
inevitably, the pressure was right down.
I topped it up.
Also bled all the radiators (none of them needed it).

Pretty much everytime I switch the heating on, the pressure rises to about 3bar (I think this is high).
Then afterwards (when its off), it drops right down to 0.3 (which is low.... I assume thats what the flashing light means).

So how come I have to keep topping up the pressure in the boiler, pretty much every time I use it? And then when its on, it gets to a flashing red light high?

Is it overflowing when you turn it on?

(There should be an overflow outlet, sticking out of the back of it.)

not seen or heard it overflowing.

My mate reckons its the expansion valve or something like that... and also suggested it would be coming out the overflow pipe.... have tried to look, but its dark now (and cant see or hear anything).

Sounds like one of your radiators might be leaking. I'd check them all to see if any are dripping, the smallest of leaks can cause the pressure to drop.

I'd echo that - a leak is a very likely cause of a rapid drop in pressure.

Do you get wet when you stand underneath it?

I have some experience with this issue with a combi... I had the same problem that went on for about 3 months despite several boiler checks and remedies by a plumber. Turned out the leak was coming from a pipe in the wall which had broken by the solder joint and had corroded the pipe going through the floor - dumping several hundred litres into the base of my house (and resulting in a 35k insurance claim and 3 months in a hotel).

I would suggest tracking all of the pipes in your central heating system that you can access and checking for leaks. Check all the ceilings to see if there is any water damage that may be appearing (although this may not show if it is a recent problem as you may have insulation) - and also time how quickly you are losing pressure as it will give you an idea of how severe the leak is - with us it started out losing the pressure every week, and by the time we discovered where the problem was (with a heat camera) it was going down every hour after re-pressurising.

Hope you get it sorted.

Surely rads needing bleeding would be a sign of a leak?