Hi,

I have a "Sime Super Four" combi-boiler system installed in the loft.
This has a built-in programmable clock which I would like to replace
with something like a DanfossFP715.

This will provide me with the useful manual and +1hr overrides, but
the main reason is to have the controls (programmer) in a more
convienent place and not having to pop into the loft access the
controls.

The Sime has a circuit diagram which shows the switches for the CH and
DHW and it looks fine. However, when I look at the wiring for the
Danfos, it is showing a live feed switching to either on/off for the 2
switches (SPDT) sending 230V to either.

The Sime looks like it is actually making/breaking a circuit, and the
small PCB has at least some 24volt components.

Anyone familiar with this boiler and know if I can easily replace the
programmer ?

I have BMP images of the Sime circuit, and a PDF file for the FP715,
if anyone is interested enough to have a look.


--
Hammy