Vaillant VRT 392F Wireless controller...

[mchoody]

Hopefully somebody can help me out. I have a Vaillant Ecotec 831 boiler fitted wired to a Honeywell room thermostat. I have installed a Vaillant VRT392F Wireless Programmable Room Controller. This (I thought!) was as easy as plug and play! I can't seem to get it to work, do I need to do anything else on the wiring side? I have removed the old Honeywell stat and capped off the cable from the boiler, this is the only thing I can think of that could be causing a problem. All help or suggestions appreciated!! M

[Arthur Jackson]

The Roomstat will be a simple switch. You may need to link across it's wires to allow the boiler to fire.

[mchoody]

I did consider that. I have the live and neutral from the boiler that did go to the old Honeywell stat. The idea of joining these together obvioulsy worried me!

[Arthur Jackson]

The Room stat will be either two wire (in which case you can join them) or three wire (in which case you join live in and live out..NOT the neutral) The boiler probably came supplied with a small link wire across two terminals to be replaced with the external controls.

[Rickyy]

If it is like the Worcester plug in programmers, you may need to re-connect the link in the circuit board.

Just googled it quickly and you may need to link out terminals 3 and 4 on the circuit board.

I am not 100% sure though, I've only ever fitted one Vaillant and that was a while ago. For some reason I seem to recall that Vaillants use low voltage switching, please don't go connecting 240v to anything unless you are sure!

[Arthur Jackson]

Yup. As Ricky says:


3 and 4 should be linked. I assume this is where your roomstat wires are connected.

[mchoody]

I've got two wires to the old stat (plus an earth obvioulsly) I'm a couple of beers in at the mo so I'll wait until the morning and stick a meter over it and check the voltage. Thanks fellas!

[Murph7355]

Have a look in the install manuals. If it's like my old Vaillant you'll need to fit a jumper wire between two terminals in the boiler (which I think is what the guys above are saying).

The manual was reasonably clear and fitting the wire a piece of piss. Which made it doubly annoying that the people who fitted the boiler couldn't work it out (took a few days of being cold before I plucked up courage).

If you have a big difference between upstairs and downstairs temps, you may find the gadget a pain in the arse

[mchoody]

Just to say that fitting the jumper between pins 3 and 4 did the trick. Just got to work out how to use the actual timer now! Thanks again all. Mark.

[Murph7355]

mchoody said:

Just to say that fitting the jumper between pins 3 and 4 did the trick. Just got to work out how to use the actual timer now! Thanks again all. Mark.

They're pretty straightforward, though my Mrs never got her around the fact that there is no "on" or "off" per se.

You set a "day" and "night" temp and the boiler does whatever it needs to in order to maintain these temps at the given times. You can then override it at will. She also never believed that it was maintaining a constant temp (it was...proven with other thermometers!).

Being able to set times independently 7 days a week and pretty much whatever times you like is great.

Vaillant are quality products IME.