HCM200D and HR80UK losing communications

[DavidS]

Hi

Twice over the past four months I have woken to find that all the HR80UK valves in my system have lost communication with the HCM200D and hence set themselves to a very generous 20C

There were no changes made the night before (in fact none barring a slight schedule change in several days). No power cut. HCM200D not complaining of anything and still showing the various valves as installed. No changes to other wireless equipment around the house. All the batteries were replaced a few months ago...

Re-installation of each valve gets them working again and the time programs have not been lost. I haven't checked the boiler controller yet to see if it has also disconnected although I suspect it has gone too.

Anyone else experienced this and if so do you have any ideas of the cause please?

Many thanks

David

[JohnnyP]

Wow - never had all HR80s lose comms at once. Very disconcerting, and warm! I've had the odd one lose comms as discussed in this thread, which includes the very detailed explanation of the "lost comms" protocol from Sensible Heat.

http://www.wordpress-1219309-4387497.cloudwaysapps.com/vbulletin/showthread.php?t=1880

One tip might save you time if it happens again - just taking a battery out and immediately replacing it will "power cycle" the HR80 and cause it to attempt a Sync (instead of re-installing).

[DavidS]

Thanks for the reminder about the power cycling

Good point about pulling batteries out - I think that I once knew (or discovered) that but had completely forgotten about it. I am looking at putting a simpler system i.e. based around CM-zone CM67 system rather than HCM200 controlled and as I won't be around to sort it out didn't want this sort of problem.

Thanks to the pointer to that other discussion which I hadn't picked up before. It is very useful to know about the synchronising attempt will continue even once the units have gone in to failsafe mode. We have plenty of laptops and wireless phones around but I don't think that any of them were nearer to the control unit than usual. And it didn't seem to happen until after the time switch on the boiler switched it off.

As aside, have you ever compared the setpoint with the temperature that you actually get. My system seems to settle for a temperature a degree or two below and only cycles the boiler for, say, a minute in 10 to maintain the temperature (a bit short given the lengths of some of the pipes in this place - can't lag them either). This is not the failsafe setting for the boiler controller as using a lifestyle to set the whole system back to a very low temperature stops it happening.

[JohnnyP]

In normal circumstances the achieved temperatures, as reported by either HR80s or remote HCW82s, are close, +/- 0.5C, to the setpoints once the system has been running for a while. However, some of the rooms in the house have undersized radiators, and when the weather is very cold (like all this winter!) these rooms never reach the setpoint and settle a couple of degrees below. Hope this helps.