The Efficient Home Forum

Hi

I currently have a S plan system fitted and installed and wired Evohome as per the wiring diagram for this type of system, I also installed the hot water kit at the same time, when I came to set the system up and went through the guided configuration I could get the hot water BDR to turn on and operate the valve bringing the boiler on, however at the same time the BDR for the heating came on, I cleared the binding as per the instructions on here and retaught the system again, the same issue happened, when I turned hot water on both relays activated, I turned hot water off the hot water relay deactivated but the heating valve one remained on. To get around this issue I had to program the system so the hot water BDR controlled the hot water valve, and then I set up the Heating BDR as a single zone, this worked as a temporary measure but not as described in the manuals.

Should both BDR's come on at the same time ?

When hot water is turned off and the BDR is also off, the valve is closed, should the heating BDR still be on ?

I have now added HR92 valve controllers to the equation, will it be best to set up the system as per the S plan wiring diagram and try the guided configuration again where you teach the hot water sensor, then hot water BDR and finally the Heating BDR, both zone valves use the orange wire to trigger the boiler. Or do I need to move and alter the wiring to figure 4 where the orange / Grey wiring is removed and I would assume the heating Valve is left open manually. Then one BDR operates the HW valve and the other operates the Boiler.

Which is the best option ?

Do I need a third BDR to control the boiler on the S plan setup ?

Regards

John Vincent

Hi John,

With S Plan and Y Plan systems without HR92's you need to do things a little differently to what you need to do with HR92's. If it is a gas boiler follow the wiring diagram for S Plan or Figure 4. If it is oil, you will need 3x BDR91 for S Plan or Y Plan so the system can be calibrated correctly.

For S Plan or Y Plan without HR92's, go through guided configuration and then zone configuration saying NO when the heat demand option comes up. Then bind one zone as a 'zone valve' zone using evohome as the sensor and the BDR91 for heating as the actuator. Then go through guided configuration for hot water, bind the sensor and then choose the 'hot water only valve' option - bind the hot water BDR91 as the actuator.

If you have a gas boiler, S Plan and HR92's - make sure 'Wireless Relay Box' is removed from the Boiler Control menu under System Devices. Then follow my video here - https://theevohomeshop.co.uk/forum/view ... ?f=12&t=29

This should cure your issues.

Thanks,

Richard