Adding a wireless thermostat to existing controller

[JamesHughes]

Hello all,

I have a digital Danfoss controller on my oil fired water and heating system, but there is no thermostat. No idea why one wasn't fitted 0- all rads have TRV's but boiler still goes on and off all the time, which I think must be wasting oil. (Cannot afford to do that nowadays!)

Questions is - I assume I need wire the new thermostat in to the controller directly? Is my controller likely to have the correct connections inside to do this - its one of these..

http://randall.danfoss.com/xxTypex/287387_MNU17416279_SIT313.html

I have looked at the wiring diagram, but am slightly confused as to where the thrmostat should be wired in.

And, recommendations for a wireless thermostat much appreciated.

James[/url]

 

[gas4you]

For a basic wireless room stat I always fit the Honeywell analogue one. Very simple to use and to fit.

The switched side of the Honeywell receiver unit will connect from the ch out terminal on the programmer and the connection this wire goes to on the terminal block (in series).

 

[JamesHughes]

Thanks Gas4You,

Just to confirm (and to ensure I get things right), the thermostat simply makes or breaks the HTG On line (N/O) - so (and I think this is what you said in your reply) is simply added in series on terminal 4 on the programmer backplate...

This make me think that I need s thermostat with VFC terminals, which, having done a bit of looking, it appears that this one doesn't....so I am guessing this particular model would not be suitable (shame - its half to price of some others I have looked at)

http://www.sunvic.co.uk/tlxrfp.htm

So, what I think is....Once I have a stat with VFC terminals, its just a matter of taking a power feed from the backplate to the receiver which I can mount next to the programmer, and connecting the HTG On line through the stat.

James

 

[gas4you]

The receiver units on a wireless stat will have a 240V L&N connection to operate it and the switched side can be VF(24V) or 240VAC. They do not connect to the 240VAC side of the unit.

So if your boiler terminal 4 sends out 24V or 240V this will be ok as long as the instructions say it is suitable for 240VAC. Propbably rated to around 3-6amps which is plenty in a ch circuit.

 

[JamesHughes]

HI Gas4You,

In that case, I am getting confused by the wiring diagram on the link here..

http://www.sunvic.co.uk/tlxrfp.htm

It appears to just have N, L and an output side - rather than two terminals for the VFC switching. Is it just a crappy wiring diagram, or does this particular model of thermostat just turn power on as fed from the N/L rather than switch another circuit?

Looking at come wiring specs for other stats they show a switch independent of the power supply which the above doesn't.

Sorry to keep asking questions! Want to make sure I don't buy incorrectly.

James

 

[twgas]

just looked at link provided and it does look as though there is NO vf switch in this model.

 

[JamesHughes]

Cheers TWGas,

I thought as much, just wanted to make sure. Shame, as this is a few quid cheaper than the other programmables I have looked at.

So, in a similar vein, what are Salus thermostats like - any good? These are about £66 on Toolstation, and also, do people find that the programmable ones are a good investment over a normal temperature only?

http://www.toolstation.com/search.html?searchstr=10255&Search=1

James

 

[twgas]

probably cheaper because less versatile. never had dealings with Salus so cant comment.