Wood burner with back boiler installation?

[skyhuck]

I assume you mean feed to rad not boiler?

 

Yes, the hot water rises, so you want the rads all slightly higher than the boiler and as larger pipe as you can afford.

[pie eater pete]

Put your rads up near the ceilings...

[skyhuck]

Put your rads up near the ceilings...

 

They need only be millimetres higher

[cornish wood burner]

First thing is to make your system safe in the event of a power cut. Assuming your DHW tank is upstairs pipe upwards from your back boiler pipe through the coil in this tank. You will also need a vent to your header tank from this line. Best to use 28 mm pipe with as few restrictions /bends as possible. Always run the flow uphill and the return down. No level runs. A meter or two head difference if any appreciable pipe length. Once you have a safe system then you can either run your rads from a second coil in your DHW tank or T off your back boiler line to your rads driven with a pump. It might be possible to run rads upstairs via gravity but you need to be carefull you have enough rad capacity to absorb the heat and enough flow to take it from your boiler. As you mentioned two rads presumably your back boiler is small.

Edited April 18, 2015 by cornish wood burner