Why is hot water coming out of my central heating vent pipe?

Question

I have replaced the pump and all rads are heating up okay, hot water system is okay but water comes out of the vent pipe like a tap...! New pump is in the same direction as the old one. Please help!

I have turned down the boiler to half it's usual operating temp and the ball value & flot has been replaced and is working fine

Also, when I incease the pump speed the flow from the vent pipe slows down, not speeds up....

PS - It's a vented system

Answer 1

James M Stop talking so much crap and read the questions before you open your big gob, the asker said running out like a tap not dripping down the flue pipe and water vapour is only a by-product oy condensing boilers

Go with Wild-eep it's the most likely answer

Answer 2

Central Heating Vent Pipe

Answer 3

I had a similar problem to this, when the hot water was pouring out of the vent pipe and nothing i did seemed to cure the problem,
i called out under my british gas 3 star maintenance contract and it even took them 5 visits to fix the problem,
visit 1) they replaced the boiler temperature switch as they said the boiler was getting too hot even though the temperature gauge said otherwise,(no change)
visit 2) they serviced the diverter valve (again no change)
next visit the checked all the boiler wiring and gas flow.(still no change)
visit 3 & 4) they checked the valve feeding the actinic top up loop and replaced it as they said it was letting by (this made matters worse as the replacement they fitted was indeed letting water by and so they had to come out and replace it again)
visit 5) they finally tracked down the problem, the pressure safety release valve was the problem, its spring and seals had been affected by the heat from the boiler, they said that it should not have been fitted directly on top of the boiler but should have been fitted further down the vent pipe out of the way of direct heat, my problem was cured and i have not had any more problems for the last 3 years.

Answer 4

I think you mean the vent pipe of combustion to the outside. If that is the case, its the byproduct of combustion. Water is byproduct of burning natural gas.

If your are running your boiler at TOO LOW a firing temp the exhause will show up as water dripping down the flue's side. You will need to increase the natural gas flow to raise the temp of the boiler s combustion chamber.

Answer 5

Is the pump you replaced the same rating as the one you took off.What i mean is, every pump is rated as "head of water". This means how high the pump will pump water vertically. If it is the same rating, then try to set the pump on the lowest setting, and see if this cures the problem. If the pump is a bigger rating than the one you took of, then change your pump for another one of the correct rating.

Answer 6

I think you need to contact companies below for problem resolving

US: http://goo.gl/kfyaUT
UK: http://mypro24.co.uk/form/central-heating-fuel-not-specified

Answer 7

is it a combi boiler (pressurised)?

if so, yeah you've over pressurised it.

If not, the problem is the ball valve in the header tank - it's stuck open. It works basically the same as a toilet cistern.

Answer 8

You have FAR too much pressure in the boiler. You need to reduce it ASAP.

Answer 9

pumps running too fast.