Hi. I'm looking to replace my current setup - programmable timer for CH and HW (Potterton EP2002), with a wired thermostat for CH (Salus RT500). Separate HW tank (Megaflo). Boiler is an old Alpha system one (non-condensing). I'm hoping (funds allowing) to change the boiler and tank next year.
I've spent ages looking at all the Smart options - Drayton Wiser, Hive, Nest, Netatmo, and Tado. To begin with, I want something that will work with my current boiler. The Hive is okay, but defaults to ITLC, and isn't configurable without contacting support - and support seems a tad bad, according to what I've read.
Nest seems cool, but has a really bad score on trustpilot, and I don't like the fact that the minimum on time for HW is 30 minutes.
For the Tado, I like the look of it, and the ability to add radiator thermostats. However, it's hard to find out how it handles the call for CH. Can it be configured as a simple on/off, or does it insist on using a form of load compensation (so, will keep on switching the boiler on/off as it thinks it's approaching the temp - which I don't want with my current boiler)?
Also, if I set the temp to 20 degrees, when will it call for heat, and stop calling for heat? - i.e. call at 19.5 and stop at 20.5, or some other values.