Siemens REV100 help needed

[Raas]

Hi All,

I'm having a bit of trouble getting to grips with this product.

I bought it to replace a very old honeywell roomstat. Upon removing th honeywell, there were 4 wires, 2 red 2 black feeding the unit i positions labelled 1,2,3,4. How these relate to L & L2, T1 & T2 I don' know!

I took some meter readings but this didnt tell me much. Ive since ha it wired up but when the central heating control has hot water and c on, the rev100 seems to get confused and alternate between 'remote' an 'burner on' modes.

I am yet to get any heat into the radiators. But there is plenty of ho water and I can here pump like noises.

If anyone has any experience with this unit, I would really appreciat some help.

Many Thanks,

Raa

-- Raas

[Andy Hall]

I have one of these controlling the heating in my workshop. It controls power to a pump which then indirectly controls the heat source.

Have you looked at the instructions?

main things are to set the DIP switch correctly and then to do a soft reset with the button next to it.

The connections T1 and T2 are to connect to an auxilliary switch. The purpose of this is to turn off the heating (for example) if a window is opened. It is unlikely that these would be used in the scenario you describe.

This is a basic on/off thermostat and the connections L and L1 are simply closed when heat is demanded.

Without knowing details of your Honeywell thermostat, it is hard to say what the connections are. Typically, theses could be contacts that make as in this case, an auxilliary heater for the bimetal strip in an old thermostat or even a cross-over contact.

It would be helpful if you could supply the model number of the old thermostat and details of which wire went where. Then it may be possible to work out what you need. Note that some thermostat arrangements actually require a cross-over contact and may not work with this thermostat directly. You might anyway need a different product since this one only has making contacts.

[Raas]

Thanks for getting back Andy.

The controller I'm using is a honeywell ST6300A (for ch and hw) in th kitchen, but the old room stat the rev 100 is replacing is.. let m just find a pic on the net.... can't find an exact one, but its 70' style gold and brown with a turny dial. Inside it has 4 connection labelled 2,1,4,3 (in that order).

I understand that I may not need to attach anything to the remot connections on the rev100, but I would like to figure out which wire are which. Especially now both units are unplugged and the wires aren' labelled. I know, I know...

Does that give you a clearer picture at all

-- Raas

[Andy Hall]

Yes.

I think that the first thing will be to trace all the wiring and to figure out what you have.

It should be one of these.

most instances, the room thermostat has two wires as the make contacts to open the motorised valve and fire up the boiler. There is a third which is connected to neutral and is used to run a little heating element inside the (bimetal) thermostat to improve response. You won't need it with the Rev100.

Once you know what you have, you need to identify the live and switched live wires.

It is possible that you have an older type of motorised valve which was driven each way under power rather than just having a spring return as most do today. These required a change-over contact type of thermostat. It is just possible that you have one of these you will wither need a different thermostat type which has a change over contact or a different valve head.

[Mathew Newton]

Is the ST6300A staying put? If so, are you sure the REV100 is a suitable replacement for a simple roomstat? Sounds overkill to me (not to mention grounds for potential confusion given the duplicated timing functions) or was the touch screen aspect just too much to resist?! ;-)

Mathew

[Raas]

Too much to resist I'm afraid. It should be adequate as a roomsta though, I am right in thinking that

-- Raas

[Andy Hall]

Certainly.

That's what I use it to do.