what are these pipes ?

hi guys , I've just bought an old house and would like some advice on identifying the pipes up at the cylinder. there is currently no central heating in the house apart from an open fire with a back boiler that heats one radiator in a bedroom , it doesn't seem to heat the water ??. I've drawn a diagram with the pipe sizes and location on the cylinder. I plan to fit a wood burner for hot water and an open vent oil fired boiler for the central heating. any advice on connecting up the wood burner would be much welcomed. Thanks in advance
not sure how to post an image but here is a link to the album

//www.diynot.com/network/Rabmcgo/albums/18804/70362

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The two going into the right hand side of the cylinder are flow/return, the 22mm going into the top of cylinder is hot domestic supply, the bottom left 22mm is cold feed from domestic tank, as For info concerning wood burner DONT DO IT.

easyflow said:

The two going into the right hand side of the cylinder are flow/return, the 22mm going into the top of cylinder is hot domestic supply, the bottom left 22mm is cold feed from domestic tank, as For info concerning wood burner DONT DO IT.

Click to expand...

I don't agree!

Rabmcgo - It looks like you have a direct cylinder although the reason for not getting water heated by the back boiler is unclear without seeing the installation complete. easyflow. got the bottom right 22mm wrong as that is cold feed from the tank and oddly the return for direct heating is on the bottom left.

You will need a new indirect cylinder or possibly a coil conversion on the existing cylinder although I would not recommend that. As for use of a wood burner I would suggest that when you replace the cylinder you get a new one to suit your needs including input from the wood burner should you want to do that.

The other 22mm cold feed from the tank could be for tank served cold water supply generally (except the kitchen sink which should normally be direct mains potable water. The 15mm may be a cold feed to a shower.

The strange thing is the flow and returns to the back boiler I would expect to be 28mm (or 1")

Edit: Posting an image - Below the text box where you type or edit your message are two icons, one for show my images and another to upload new images. Click the show my image and select the one from your album

Sounds right Blagard,

Re the woodburner/oil boiler. I think it's worth looking into systems that can combine the heat from both of them. Things like a Dursley Neutraliser, a thermal store.

Thanks guys for the feedback. I was going to fit a twin coil tank , one coil for the radiator circuit and one from the back of the wood burner for hot water .I was hoping to use the pipes running down to the back boiler for the wood burner , do you think this is possible ?. is the radiator that runs off the back boiler there to draw heat from the back boiler in case it gets to hot ? I've uploaded the image again but with numbers beside the pipes for clearer identification. im still not sure what pipe number 1 ,2 and 3 do. my biggest concern is connecting the wood burner because doing the central heating circuit seems handy enough as it'll be a new install.

1 and 3 are logically the flow and return to the back boiler but where 3 goes, well... you tell us? Is it a disused and capped off pipe that was once the original open vent to the back boiler and replaced by the one you have drawn? It could also be where a safety pressure release valve was fitted in the past.

You can use old pipework if you know it is sound. I would also suggest that if any old compression fittings exist on the pipes they are replaced with soldered connections when you re-plumb. Personally I would replace it all and know it is installed correctly. You obviously have not been able to trace the pipe route or find out why the hot water is not getting heated by the back boiler otherwise you would know for certain if 1 & 3 are the flow and return

Fitting a thermostat on the wood burner flue could be used to shut down the hot water primary from the boiler to avoid coils competing with each other. fitting a pump on the wood burner primary may be desirable if only 22mm or if the coil is unsuitable for gravity circulation - this would also be wired to the flue thermostat

A radiator on the back boiler is really only to make use of the available heat source. It is possible that it was badly plumbed in destroying the gravity circulation to the hot water cylinder