Drayton MiStat wireless progstat (first impressions)

[John Stumbles]

I fitted one of these today. It was to replace an older Drayton progstat whose relay box wasn't switching (green LED came on but boiler didn't fire up). The new relay unit has an industry-standard(-ish) backplate like single channel programmers/timeswitches so swapping it was a doddle, whereas if I'd been fitting a Honeywell CMT927 as I'd originally planned I'd have had to change the mounting and wiring.

First impressions was it's even easier to set up than the Honeywell - even comes set to the right date and time, and has a sensible default programme (5+2 days, 2 heating periods morning and evening for weekdays). You could pretty much fit it and run away and it would work well enough.

Unlike the Honeywell which has holiday, day-off and party mode buttons you have to get to these through the menu on the Drayton and the holiday mode, at least, seems deeply unintuitive, unlike the Honeywell which really is a doddle to use (except for being a bit confusing whether it will still be in holiday mode on the end-of-holiday date or will it go back to normal the day before).

I really need to play some more with one to know its other wrinkles.

Installer mode is a lot easier to get into than on the Honeywell where you have to do this sort of masonic handshake to get into it. And one feature it has is a Landlord's (Service Interval) mode where it will cut back the heating after a certain time, to "incentivise" tenants into getting their Gas Safety done (or, on the planet I live on, get them to hassle their landlord to get it done).

Another feature is an indication of wireless signal strength. Interestingly this is displayed on the remote unit rather than the relay box, so there must be 2-way wireless communication between the units. (As far as I'm aware on the Honeywells it's just one way, from the remote unit to the relay unit.) If the remote units can receive as well as transmit it opens up the technical possibility of having a joined-up network of units operating in sync from some central controller that can talk to the remotes in a multi-zone set-up. (And that central controller could also have an interface to the internet etc.) Whether Drayton have made that possible in their design of the remotes is another question.

[Chris J Dixon]

I have often wondered about that. What is your conclusion?

Chris

[Roger Mills]

I think it indicates the day on which the heating will revert to normal, but - having said that - I *have* cocked it up once or twice, and come back to a cold house!

[John Stumbles]

As soon as you press the holiday button it says 1 day and shows tomorrow as your return date. So if you're just away on holiday today it'll be back to normal tomorrow. Therefore the return date is when it resumes its normal programme.

I think ;-)

[fred]

I certainly can't fault your logic, the manual even agrees with you :-)

"At midnight the holiday counter will be reduced by one until the selected number of days have passed." (Honeywell)

Thanks for the review, I see that it can be programmed for basic on-off mode too (as well as proportional and prop + integral) which is one step ahead of the honeywells, I've never like forced cycling 6 times an hour even though it can reduced to 3. My place has high thermal mass so the stat clunking in once an hour for a nice lazy boiler run is fine for me.