Adding a room thermostat

[The Natural Philosopher]

30 seconds, not minutes

And I do other things like unload the dishwasher...in those 3o seconds

[Roland Perry]

In message [e-mail]>, at 14:31:16 on Fri, 9 Oct

2020, "Dave Plowman (News)" [e-mail]> remarked:

I've got a wood-burner for that!

[Roland Perry]

In message [e-mail]>, at 18:28:15 on Fri, 9 Oct

2020, Andy Burns [e-mail] remarked:

Not only that - the cable's already there. The cable also doesn't have a battery in it that will need replacing one day (can you tell I'm getting very fed up with replacing batteries?)

[Roland Perry]

In message [e-mail]>, at 18:31:41 on Fri, 9 Oct

2020, Andy Burns [e-mail] remarked:

OK. I'll consider something like that if I need to replace the controller.

[Andy Burns]

Yes, that would put me off the idea of individually controlled TRVs

[Dave Liquorice]

Ah, equivalent of letting this place cool down, high thermal mass.

[Dave Liquorice]

A lot of programablale stats time switches etc are "volt free" on the contacts ie. not connected to the devices supply (mains or battery) internally. The switching bits are mains rated so the actual control circuit can be low voltage or mains.

I thought there was a standard wiring layout for thermostat back plates but as with many standards there are so many to choose from... I sort of side step that issue by bringing every connection from a stat, switch, motorised valve, etc back to a wiring center and fitting jumpers as required to create the correct circuit(s), I like the ACL Lifestyle LWC1.

[Andy Burns]

^ ^ t s

[Roland Perry]

And most of my TRVs are in rather inaccessible places (mainly behind bits of furniture).

[Dave Plowman (News]

Last thing you want is an all house stat in the same room as an additional heat source like a wood burner. That will simply kill the heating to the rest of the house.

[Dave Plowman (News]

Mine had a long lived battery. With a clever type of relay (taking a very small current from the battery) to switch the boiler.

Although I already had a neutral and earth run to the thermostat location (triple and earth)

[Dave Plowman (News]

Means the rads are too?

[Roland Perry]

In message [e-mail]>, at 11:26:22 on Sat, 10 Oct

2020, "Dave Plowman (News)" [e-mail]> remarked:

The stat isn't in exactly the same room.

And why does that matter, if we are all in the room with the log-burner?

In fact, it's actually a positive outcome.

[Roland Perry]

In message [e-mail]>, at 11:30:41 on Sat, 10 Oct

2020, "Dave Plowman (News)" [e-mail]> remarked:

Some bits of the rads are, but especially the ends. A couple of the bits of furniture are tables/desks, and don't prevent the heat getting to the room under the tabletop (and of course up the wall too - but that's because what we call "radiators" are actually more accurately "convectioners").

[Dave Plowman (News]

Right. So what exactly is this all house stat seeing?

Not much point in having central heating, then.

[Dave Plowman (News]

A TRV works by convection too. And anything which restricts the flow round the rad will effect the output.

[Roland Perry]

In message [e-mail]>, at 16:31:41 on Sat, 10 Oct

2020, "Dave Plowman (News)" [e-mail]> remarked:

The temperature in the new kitchen/diner extension.

The central heating is manly for the early morning, when I never have the log-burner operating.

[Roland Perry]

In message [e-mail]>, at 16:33:44 on Sat, 10 Oct

2020, "Dave Plowman (News)" [e-mail]> remarked:

Never had any problems so far in the way they affect the output.

[Andy Burns]

In which case, a programmable stat has another advantage, you don't tell it when to turn on, you tell it when you want it to have reached target temperature ... it learns how quickly your house heats up and on colder mornings it comes on earlier.

[Dave Plowman (News]

A kitchen isn't the ideal place for an all house thermostat given temperatures can be very high in there when cooking.