Identify Central Heating Layout.

[Smokepole]

Hi. I'd be grateful if anyone can help me understand how this hot water and heating system works. I have a oil boiler supplying a cylinder in the hotpress and on it there is a mains cold water feed going in around a coil and out hot to a mixer v/v for taps, thats simple enough. The issue is how is the central heating system working? The flow and return from the cylinder are at a midway level and pumped around the rads, is this also on a coil within the cylinder?

 

[Rox]

Suggest you look at the various Sundial Plan Reference Guides (eg S Plan, Y Plan) on the Downloads tab at Honeywell United Kingdom Heating Controls
They show a simplifed pipe layout and controls wiring.

 

[tamz]

If it is a lagged cylinder (yellow or green), it could be an old Albion mainsflow cylinder or similar. Most of the manu's did them at one point (thermaflow, flowmax etc). A kind of thermal store.
You could get them in direct or indirect. Direct had 1 coil, indirect had 2. Early versions had no blending valves.
If it is a white cased model it could also be a Gledhill. There should be a label on it somewhere.

 

[Smokepole]

Getting somewhere now. Looks like the Albion cylinder. With second pump for heating. Now the big question..what type of boiler would i need when changing to mains gas?. existing oil boiler is a two pipe set up. Thanks all.

 

[tamz]

If you want to keep the cylinder (or a cylinder) you would need a regular (if you have a header tank) or system boiler (if you don't).

If you don't want to keep the cylinder get a combi if the house is suitable.

Best speak to a local installer.