Draton Tempus 7 to Digistat+3RF

[brooky_agb]

Hello,

I was wondering if one of you lovely people can be so kind as to help a neewb like me. I have been learning lots and I have almost got the rads balanced in my new house after cleaning with Fernox. Now to change the programmer....

Currently I have a Drayton Tempus 7 which is wired for JUST heating not hot water. I want to replace it with a Drayton Digistat+3RF which I ordered this morning.

Below are pics of the current wiring and wiring digram on the back of the tempus 7.

The wiring diagram for the Digistat is below:

Now Negative & Live are the easy bit. I assume ground can be isolated easily somewhere (hopefully that is clear when the unit arrives). But with the tempus 7 that only leaves one wire... "Heating On".

Do I just connect that up to pin 3 and leave pin 1 & 2 with no connection?

 

[stem]

Correct, terminal 3 is the one you need, But on the Digistat you will also need to link the live terminal to terminal 1 (Common). Otherwise you will not get a live on terminal 3 when it switches on.

This link is made internally on the Tempus.

Congratulations on the clear and informative post BTW. Often there is insufficient information given requiring guess work & assumptions.

 

[brooky_agb]

Excellent thank you Stem. So to achieve that I will need to add an extra brown wire from the live to terminal 1 to extend it out if you like?

I really hope this helps others too.

 

[stem]

Drawing below. If you look at the circuit diagram of your existing unit, you will see that the connection on that is made internally.

Untitled

• stem
• 24 Nov 2009
• 1

 

[brooky_agb]

Gotcha. Can't thank you enough.

 

[stem]

There's a "thanks" button on the right specifically for that purpose

 

[brooky_agb]

Ok, you're all thanked up.

 

[brooky_agb]

Unit was a breeze to fit apart from getting the three negative wires into one terminal .

Its working great turning the heat on and off but..... this morning the unit said the room temp was 17 degrees centigrade. It was scorching!! Do you think it is faulty or should I move it nearer a radiator. Right now its about 1.5M high on the wall with no door or radiator near it.

As its working now I can't see it saving our heating bills which was part of the reason for buying. Anybody else experienced this?

 

[stem]

Don't move the transmitter near a radiator, the idea of the thermostat is to sense the ambient temperature in the room as the occupants would. The instructions will advise installing them away from heat sources, draughts or direct sunlight.

The human body is not a good thermometer, warmth is relative, depending on the temperature of where you've just been & your level of physical activity etc., However, if you think it's not showing the correct temperature put a thermometer on top of the transmitter and see how it compares. I'm assuming the "scorching" refers to the room where the transmitter is located, not elsewhere in the house, or the radiator itself.

Is the wall the transmitter is mounted on internal or external?, sometimes mounting a it on a cold external wall can give a lower than actual reading, or in a corner or alcove can shield it.

Sounds like it was working OK the night before though if I read your post correctly.

 

[brooky_agb]

Yeah its on a partition wall 1.5m above ground level away from rads & door.

Maybe its just me not feeling the cold after a few beers. :S

Thanks again.