Smart thermostat recommendations

[querquetulanae]

Afternoon all,

We've recently moved home and are about to upgrade our existing old boiler / HW tank to a Viessmann 35kWh combi boiler.

There was a LOT of debate as to whether we should go for a new powerful combi or a system boiler with Megaflo unvented cylinder. We're a family of 3 with not significant hot water demand, so decided that we didn't need the additional cost of installing the cylinder and pipework...at the risk of potential water pressure drop issues!

We have central heating (radiators) upstairs and downstairs, and a wet underfloor heating system downstairs on two separate heating 'loops'. These separately call for heat from the boiler. They currently have wireless room thermostats to control the temperature, and have separate control units inside our airing cupboard.

I want to buy a smart thermostat which would ideally integrate both the radiators and underfloor heating, plus be compatible with OpenTherm. Looking at Tado and Drayton.. is it possible to hook all this up to a single system?

That sounds like a more specialist system.

I don't know why you think there would be water pressure issues with a megaflow. If installed correctly the hot water is backed by mains water pressure - that's really the whole point of it - hot water at cold water pressure. I have it and it works great - definitely the way forward IMO.

I don't have a clue about your thermostat requirements, but I have Hive. It appears to have multi zone capability. I wouldn't recommend it, because I have the distinct feeling that they are trying to squeeze more money out of it, and I think they have already cancelled some sensor functionality (not the thermostat) to a fair few peoples annoyance after they bought the sensors.

Good luck !

Ah - that should have read we've gone with the combi option at the risk of having pressure issues (e.g. when in the shower and someone starts the washing up). We debated for about three days which system to get before making the decision - and I'm still not 100% on it!!

I would get advice as it depends on which system you chose. We have the same set up as you with UFH etc and separate circuits but opted to remain with a cylinder for water. I looked at the smart option but it simply wasn't worth it given our very consistent lifestyles. With one system (think tado) you just bought additional controllers but one lot you needed two separate router type controllers plugged in.

What I would suggest you consider is the smart thermostats so you can control the rooms you don't need heating all the time, ie bedrooms