Any boiler/heating experts on here?

I've been losing pressure and having to top up my boiler every day or 2, with no signs of a leak from radiators/pipes (although if it were under the ground floor floorboards I wouldn't know).

Heating mester came out to take a look and fairly lazily said that it must be a leak somewhere. I asked if it could be the heat exchanger that has sprung a leak/bust - he said no as he pulled the condensate pipe out and nowt was dripping.

Since he's been gone I've left the heating off (been off a couple of hours now) and pulled the condensate pipe out of the boiler and put a bowl under there. It doesn't drip steadily, but every 15 mins or so it pisses out a burst of (cleanish looking) water. Does this mean the heat exchanger is likely to be knackered? The boiler is an ideal logic combi.

 

I had that problem a couple of years ago and was told that it needed a new expansion tank. It seemed to fix it.

Edit, in my case I never saw any water coming out of the boiler, I assume it went out of the condenser outlet.

 

My understanding is that if its the expansion vessel the pressure will rocket when the boiler is on, and mine doesn't

 

Exactly the same problem with ours a couple of years ago.
It's a Baxi combi boiler and 13 years old. The new expansion chamber cured it.

 

The pressure on mine didn't rocket either. Now I think about it, he also replaced the valve on one end of the filling loop so it might have been that.

 

Is it a baxi?

 

Ideal. I've isolated the boiler from the system and it's still glugging out the condensate so looks like it might be the heat exchanger

 

Mine was a Worcester Bosh. Whenever the heating was on water dripped from the pipe outside and then pressure dropped when the system cooled down. If the heating was off , the pressure didn't drop. He replaced the expansion tank which cured it

 

I don't mind an old boiler. I've serviced a few in my time.

 

I have an ideal logic and had a similar problem. After several visits by different blokes mine turned out to be the valve that goes into the vessel. Its looks like a little bike valve, put a new un in and its been OK since - touch wood.

 

It is the expansion vessel that needs re charging, would you like me to sort it?

 

It’s very rare a heat exchanger splits, I’ve known it once in 20 year

 

Is that likely to be the case even though I left it sat for about 3 hours completely turned off and isolated from the system (and the expansion vessel) and it still kept dumping water?

Wouldn't it be losing water through the pressure release valve and not the condensate if the expansion vessel were knackered?

 

If water is coming through the blow off (pressure release) pipe, outside, then it is highly likely to be the expansion vessel. If you can locate the valve for this ( looks just like the valve on a car tyre as it is the same) you can try recharging your vessel, via this valve, simply with a bike pump. Get it up to about 0.7 bar on the boilers pressure gauge, then take it to just above 1.0 by topping up with water through your filling loop, then go outside and check if your blow off is dripping or weeping. If not, you may have cracked it. If so, you may need a new vessel, but if you have space, you can simply ‘tee’ one in outside of the boiler casing which will save a fortune.
Good luck

 

There's nothing coming out of that, just glugs of cleanish looking water out of the condensate pipe every few minutes (seem to slow down as the pressure drops) even when the boiler is off at the mains for a few hours

 

I'm an expert in dealing with old boilers. What particular issue do you have? I'm guessing having to listen to ABBA Gold repeatedly?