Adding a wireless thermostat

[Woby Tide]

Apologies for a query I know has come up a few times in the past but whilst all the previous topics answer some of the questions I have, I'm still not sure it answers my query.

Currently have an oldish conventional boiler located in the kitchen. The cistern and programmer are located together in the airing cupboard. The programmer currently is a Danfoss FP715 Si(or variation thereof but it seems to match my setup), on a standard wallplate, I can set independent times for HW and CH. There is no room thermostat (wired or otherwise) in the house. The radiators in all rooms bar bathroom have TRV controls(bathroom rad is bypass I beleive).

Is it possible (and does it actually exist) to install some form of wireless thermostat/programmer and retain the current functionality? The ideal situation will be to install some form of wireless transmitter in the hall that will act as the thermostat for the CH (that I can program times/temperatures) but also allow me to set HW timers from there (we only currently set the HW to be on a couple of hours a day so I'm not sure I need some form of thermostat/temp control for the water).

If that isn't possible the other alternative is to retain the programmer functionality within the airing cupboard but incorporate a wireless thermostat for the CH only. Again I'm not sure if that exists without requiring extra wiring at the programmer which I want to avoid if possible.

I guess my main requirements or ideals are to retain the standard wallplate and gain some form of thermostat control elsewhere in the house without the need for wires. Retaining the 7 day programming capability is the other ideal due to shift work/part time work that family members do so we have different heating profiles each day currently.

I've seen things like the Danfoss TP7000RF but I don't think that this retains the control of the HW from the programmer, also the receiver looks like it won't just clip onto the existing wallplate.

Thanks in advance for any help.

[Roger Mills]

I'm not aware of anything which will replace your existing programmer and do exactly what you want without any wiring changes. However, you *should* be able to achieve the desired result with only minimal wiring changes.

You can keep the existing programmer and let it continue to control the HW. But, for CH, set the programmer to 'Continuous' and use a programmable thermostat (wired or wireless) to do the actual timing and temperature control. The small wiring change is that you will need to locate the CH demand output wire from the existing programmer and divert it so that it goes via the programmable stat.

[In giving this answer, I'm taking at face value your statement that you currently have independant control of CH and HW, which I interpret as having a fully pumped system with appropriate motorised zone valves, etc. If you've *actually* got a gravity HW and pumped CH system of the sort where you cannot have *just* the CH on, what I said above doesn't apply].

[John Rumm]

Depending on the boiler, it may even have separate connections available for a programmer and a stat. If that were the case then its even easier

- just add a prog stat (wired or wireless) and use the programmer as you describe (i.e. control the HW, and leave on continuous for CH).

[The Natural Philosopher]

Just install the stat in series with the current progrmmed output.

That what I did.

Its basically simply a relay that closes on 'call for heat'

Thats a bit of an ask.

no more than intercepting the switched live feed out of it. It MST have a separate DHW/CH switched feed to control the motorised valves.