Remote (that is, when away from the house) control thermostat

Indirectly ... I have a heatmiser wifi programmable thermostat, you can expose it to the internet via port-forwarding and use a mobile app, but the app was found to have totally s*it security, so I only allow it from local IP addresses ... but I have a VPN.

Yup. but you wouldnt like it

As was mine

I have a Pi Zero W running code attached to my own 4 mains relay board running a small website that accepts data from thermometers based on Pi PICO Ws and has a fairly complex set of rules as to what temperature at what time. Its a 4 zone setup - one is DHW - but only 3 are currently in use.

You need to be able to at leats understand C and Linux and be able to solder to make it all work, but happy to provide PCBs, 3D printed cases and code if you are interested

I can understand C, and have even programmed in it a long while back.

I used to be a Unix systems administrator at one time as well, so I understand Linux and have run it in the past but have no real need for it at present.

I can solder(ish) but not as well as an amateur electronics enthusiast.

Thank you for the very generous offer. At the moment I have a massive backlog of things to do so a DIY project of this kind would be too much additional load.

I was really looking for a "look! shiny!" at an amazingly cheap price. It is almost Xmas and a passing sled might chuck something out.

Cheers

Dave R

Search your favourite tat bazaar for 'wifi thermostat'. You can get them from about £20 - Moes is one brand and they're usually on the Tuya smart platform. You can control them from the (Chinese) app.

They have relay outputs for heat and some do hot water. But what I'd suggest is put it in series/parallel with your existing wall thermostat. Then you set the wall stat to an 'idle' state and the wifi stat takes over. eg if in parallel, you'd set the old stat to say 5C as a frost stat and the smart stat would call for heat by shorting it. Or for series, if you're worried about being roasted by a faulty smart stat you might set the wall stat to the maximum safe temp and allow the smart stat to turn off the heat to keep it lower than this. Maybe you could have a bypass switch to remove the smart stat from circuit to put things back to normal when you're at home.

It's all pretty crude, but if you have an old heating system then it matches the crudeness.

Theo

My Hive system provides remote control very effective. (As would a nest system, I believe).

But they do rely on a remote server which could - in theory - disappear at any time.

It may be worth looking at their latest offerengs -there may now be some which don't need an internet-connected hub.

I was in a similar situation, and solved it by buying a Tapo Smart Plug, which you can get from Toolstation, Argos etc for about £10. It's programmable from an App on your smartphone, assuming you have one.

All I've done is plug in the central heating system via this smartplug and turn it off when we leave, and then on again a few hours before we are due back to allow the house to warm up. This avoids all wiring changes, as would be needed to put in an alternative or duplicate thermostat.

With my setup, it means that the normal timeswitch is off the whole time that we are away, so depletes its backup battery which keeps the clock in sync, but so far that hasn't been a problem. The Tapo has a lot of functions that I have not used, but for merely remotely turning something on/off it seems fine. I've used it twice for short holidays so far, and it's worked fine. I was even considering getting another Tapo or two to control lights etc.

You have to set the Tapo up with your wifi router, but it's a fairly simple process. This probably means your wifi password gets passed to the Chinese Government, but I expect they know it already. In fact I was a bit surprised that Tapo didn't tell me what my password was rather than have me tell it - this friend of Prince Andrew obviously hasn't been doing his stuff properly. :-)

I too wondered about making something myself with a Raspberry Pi and a bit of programming and soldering, but if you can get a gizmo off the shelf that does the job almost instanly, why bother, I thought.

Regards

Which the server for the older Nest cameras did ...

I already have a wireless thermostat (Honeywell or near offer) so I don't have a wall thermostat. The solution would have to work alongside this thermostat, or replace it completely as far as I can see at the moment.

I can't just turn the CH off because I need frost protection - in fact the home insurance requires a minimum temperature to be maintained when the house is left empty.

We travel abroad over winter sometimes, and we also use our motor Home all year round.

Cheers

Dave R

Like Roger we have Hive Smart thermostat and Hive Smart TRVs on all but the bathroom radiator and the minimum temp you set by default is 7degC. At the last house with the boiler sited in the garage we had a frost stat alongside and the minimum you could set was 4degC.

Richard