Confused about my heating system and how to bleed it...

[dmiller]

Can anyone help explain to me how my central heating system works?

I have been in this house for two years and it has been fine but I don’t really know how it all works and its bugging me. Also I don’t really know what to set the thermostat in the loft too. Also its started to gurgle a wee bit so might need bled?

So I know the following:
- Its a gravity based system.
- Its coal / wood back boiler.
- I have a feeder tank and a hot water tank in the loft.
- The hot water tank has a pre-heat bit above it and I have wrapped it in loft insulation to try and keep the heat in it.
- There are two floors in the house, upstairs has 3 radiators (on 8mm copper) that goes to a large (22mm?) copper pipe under the floor. The pipes are fed in and soldered. The downstairs has 4 radiators on 8mm copper that does the same thing to again (22mm?) copper under the floor.
- There is a pump near the back boiler. It has three settings and is currently on 1.
- There is a thermostat in the loft on the bottom (hot water feed from back boiler?) pipe on the water tank. Its a Danfoss AT (pl.heating.danfoss.com/PCMPDF/DKBGPB030B249.pdf).
- There is an immersion heater in the tank as well.
- There is a switch for the pump downstairs. The pump also comes on automatically (I guess the thermostat?) sometimes. The switch lights up when it does this.
- There is a bleed valve at the front of the house for draining the whole system.

So... how does it all work? Anything I need to be aware off? Whats the best setting for the pump? How do I bleed it?

Some pictures.
Fire:

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• dmiller
• 11 Dec 2012
• 1

Pump:

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• dmiller
• 11 Dec 2012
• 1

Thermostat:

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• dmiller
• 11 Dec 2012
• 1

Hotwater Tank:

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• dmiller
• 11 Dec 2012
• 1

Header Tank:

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• dmiller
• 11 Dec 2012
• 1

Cheers,

David.

 

[Agile]

The FAQ are meant to cover most of this!

 

[kevplumb]

if its working ok leave it alone oh and ignore the pretentious pratt that thinks he knows everythinghe wont explain it cos he dont understand it give him time to ask some advice then im sure he will be back with some load of cobblers

 

[45yearsagasman]

Welcome back Kev, the forum has missed ya.

 

[ianmcd]

if it aint broke why try to fix it ? if everything is working and the rads are heating up ok and the HW is fine then the noise isnt anything to worry about

 

[kevplumb]

Welcome back Kev, the forum has missed ya.

been away marra making some proper stuff

500 kw ladle heaters

• kevplumb
• 1 Dec 2012
• 2

sharp cook yer eggs on them puppies

 

[Nige F]

if its working ok leave it alone oh and ignore the pretentious pratt that thinks he knows everythinghe wont explain it cos he dont understand it give him time to ask some advice then im sure he will be back with some load of cobblers

- you only replied cuz it`s a Coal fire

 

[kevplumb]

dont start you

 

[dmiller]

Agile, sorry but I cant find much in the FAQ for a system like this. Everything I can find talks about thermostat for switching on a boiler to run the radiators but my boiler is always on so I was curious to know what effect the thermostat has and if I should be playing with it. For example if I turn it up will it run the pump longer or will I get very hot water in the tank? Can I fiddle with it or is it "balanced" like the side of the radiator you leave alone? If I turn the pump up will my radiators get hotter or will I just increase the pressure and risk more leaks?

The noise only worries me as it wasn’t that bad two years ago...

I can find loads of information on newer systems but not as much on older systems and was looking for a bit of info.

Most of my neighbours have gas or oil (they converted when it was cheaper) so I cant ask them. If I do the sums its a long time for that conversion to pay for itself with current prices so ideally I would love to keep my current system ticking over and working fine until something like ground sourced heat pump or solar water heating / electricity generation moves into my price range or until the sheer inefficiency (and Im assuming its not that efficient) of my system means much grant based goodness to move onwards. (If I had a gas back boiler local grants here would be available to help replace but not solid fuel). Plus I love burning stuff.

Cheers,

David.

 

[kevplumb]

yem not gonna get good advice from that pratt

bide a while and let the boys think

we will come up with something but remember we aint looking at it