Trvs calling for heat but Tado doesn't activate boiler until hot water comes on

OK so a bit of an update in case it helps someone who finds this post whilst having an issue themselves. After work on Friday I decided the best thing to do was strip back the system to a manual programmer and room stat. I did have an hour on doing packet captures across the IP address of the Tado bridge to the internet router but that's what IT Networking people do for fun so I won't ex[and on it here.

Objective was to see if it was a Tado issue at all. The old system had the same symptoms, 'intermittent CH on'. It looked like the 3 way valve header wasn't triggering the orange wire to send power to the pump (in my Y plan system). "Luckily" it was a version of the Honeywell where you could replace the valve header without draining down the system (but £85 lighter!). After a trip to find one in stock and "exercising the wallet", replacement complete but it still wasn't connecting every time. I took it off again and then discovered that the ball in the copper T piece wasn't moving. I'm not sure if it was completely seized but it wasn't moving the 60 degrees I found referenced in a post somewhere. Tapped it gently, worked it with pliers and generally "fiddled" and now I can move it easily with just my fingers. And it's only moving 60 deg. Apparently if it goes further then you've really broken it and need a new copper T piece, including a drain down which I definitely didn't want to do. Put it all back together (whilst whistling as surely this was it!!). Definitely better but still not there absolutely every time. In the end I bent the triggers for the microswitches so that the bottom one engaged every time. Having spent most of the weekend on it, I'd had enough! Those valve headers look like an archaic mechanical way of setting a 3 way valve. There must be a better way!? Would 2 x 2 ways better, although appreciate that'd be a wealth of new copper workings and probably too big a job in a confined space / retrofit?

After that was working 100% on the old, manual system I set about recreating my Tado home setup. Now there I found that order was very, very important. You can't just whack all the assets back in the device list in any order. It has to be Internet Bridge, Extension Kit and first Smart Thermostat. Otherwise it'll not be setup for Hot Water heating. And if you want the Smart Thermostat to be wireless rather than wired then don't forget the jumper in the wiring for the stat! Then add the TRVs and any extra Smart Thermostats.

So apologies for long post but hopefully that'll help someone in the future.