Huge fire leading to gas explosion

[Axel]

Not really, just wrote that title to get someone to respond to my post:

My CH system is sucking in air - the symptoms are that when it first comes on at 6am, no probs, but then by about 7 the thermostat cycles and when the pump comes back on there is a lot of bubbling and gurgling in a particular upstairs radiator as air has been sucked in or boiled out of the water and then pumped to that radiator.

The boiler is also kettling somewhat.

It's a Potterton Kingfisher CF on an open vented system with the pump on the return.

Could the kettling be generating air bubbles which are ending up in that rad, or is it most likely to be air being sucked in, and if so, what is the best technique to locate this unauthorised air intake?

 

[kevplumb]

It's a Potterton Kingfisher CF on an open vented system with the pump on the return

you have a small leak somewhere

pump on the return puts the system under negative pressure

so will draw air in

 

[Axel]

Thanks Kev, but can you advise me on a good method to detect the location of this leak ? - it's air going in, not water coming out.

 

[seco services]

the air willbe drawn in the vent pipe over the f/e tank in loft.

 

[kevplumb]

possibly rad valve glands or pump valve glands

 

[Axel]

By 'gland' do you mean the locking nut around the spindle that operates the valve, or the compression joint where the pipe goes into the valve?

 

[Agile]

Usually its easier to move the pump!

It can be very difficult to find small air leaks. It can also be gas formed by corrosion or sucking air down the vent pipe.

Have you checked the levels/layout of the F&E tank and vent pipe?

Tony

 

[kevplumb]

nut around the spindle

look for signs of leakage

View media item 11427

 

[Axel]

What I was wondering is if there is a technique to see if there is an air leak - like using washing up liquid bubbles, only that might not work as well if it is a suction 'leak'?

 

[Axel]

Usually its easier to move the pump!

It can be very difficult to find small air leaks. It can also be gas formed by corrosion or sucking air down the vent pipe.

Have you checked the levels/layout of the F&E tank and vent pipe?

Tony

Good advice, Tony. I had planned to redo the whole thing this summer - convert to sealed system and move pump etc, but now it's a bit chilly to risk no heating for a couple of days. Have been offered £2700 worth of Warmfront grant, but not sure where they would put boiler as old one is a CF inside kitchen fireplace and there is seriously no other suitable location with or without a condensate waste option.

Can you get co-axial flues that go up a chimney 10m ?

 

[Agile]

You can get the flues! But not a normal option.

Condensate can be pumped up 3m and along 6m !

It should not be a difficult task to find a workable location. Has the loft been considered?

Warmfront like a simple ( cheap to install so more profit ) solution.

Tony

 

[Axel]

The irony of the matter is that I am doing the gas APL next month, but have to get warmfront involved to get a free boiler! Might be a false economy...

 

[bengasman]

Search the forum thoroughly about warmfront/aega/iguana and what have you, before talking to them. Yes, the boiler should be free. But be aware that the quality of the boiler, the workmanship, and choice are not far above 1, on a scale of 1 to 10. Lots of their installations are subbed out to guys that get about 200 squid for the installation, and apparently they favour whatever model they can buy cheap, e.g end of line Ideals.