fully pumped or gravity fed

13 Jan 2006
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United Kingdom

Looking at the pics would someone be able to tell me which type of CH i have, just moved to a new house and I have a Hortsmann centaurplus c27 programmer which looks to be set to gravity fed, meaning i cant have CH and HW on individually, I have the jumper switch to set it to fully pumped but don't want to do this until i know for sure what type of system i have. If it is fully pumped what changes if any would i need to make to the wiring configuration to allow me to operate CH and HW individually.

Thanks for your time and expertise.
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Thanks Dan, The horstmann programmer install book shows the following 3 wiring diagrams for fully pumped systems. Any ideas as to which one i need and what wires would need to move where from how its wired at the minute.

Many Thanks.

Try refittin the prog and then turn on the CH only, (set to fully pumped on back of prog) see if it works
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You need number 6 on the pic you posted, the wiring looks ok apart from the extra wire you have on 3, you might have to trace how its wired up.
Looks to be fully pumped but wired so you can't have CH separately. I'm assuming that's why you have more than one wire in the HW on terminal.
A picture of pump and motorised valve would be good.

Either of two red wire into HOT ON number 3 should be in number 1 if there is a mid position valve fitted. A check /photos on wiring centre would be good.

Thanks for all the help so far.

twgas, i set the programmer to fully pumped and put CH on but boiler did nothing.

stardanny, not sure what you mean by wiring centre (sorry), if you can point me in the right direction i will get some pics which might help, have taken a few more of the boiler itself which may help, or not!

Where the other motorised valve? You look like zone valve so there should be two, one for hot water and one for heating.

Take a overview picture of boiler with pump and pipe work and another picture of hot water cylinder with pipe work as well.

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