Vaillant Eco-Tec Plus 831 - Heating coming on on its own.

2 May 2013
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United Kingdom

we have a Vaillant Eco-Tec Plus 831 Combi along with the wireless VRT350F Wireless Programmer Thermostat.

This evening it was noticed that the rads in the house were on. When I checked the wireless thermostat the room temp read 19c... yet it was set to come on for 17.5c... so it shouldnt activate the heating to turn on.

So it has basically came on by itself. Checked the boiler display just now and the flashing radiator icon is off... but its something i dont want to happen and increase my bills.

Anyone know what the reason may be?

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Does the 350f receiver (plugged in the front of boiler) have a green light
Is the radiator flashing on the screen?

How old is the boiler? Does it have 2 knobs on the front one for htg ken for hw
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No radiator icon on there at the moment...I don't know if it was on earlier whilst the rads were heating up. (The rads have cooled down now).

I must also add that it must of turned the heating off by itself I haven't done anything other than press the wireless room stat knob so the display turns on.

Boiler was installed in august last year.
Has the power been off? These take ages and do weird things to reset themselves if powered off
Go into the menu on the 350 to see how good the good the rf signal is between the boiler and the thermostat, it will rate it from 1-9. If the signal is poor and it can't communicate with the boiler the heating will default to the on position. Or maybe move the thermostat closer to the boiler and see if it stops the problem.
I think that may be the issue. The rf signal is fluctuating from 2 - 5.

Wonder whats the problem. Baby monitors? WiFi?

The stat isn't that far away from the boiler. Boiler in kitchen. Stat is in hallway outside kitchen door. 4metres in straight line.
Give vaillant a call under warranty, they will probably replace it. It sounds a little dodgy with such a poor signal and only 4 meters away from the boiler
Let us know how you get on, Vaillant replaced my VRC430f which was using up loads of batteries. The new one hasn't needed new batteries for 2 years now :)
Yeah will do. Going to test it tomorrow when baby monitors are all off... Will see if that's an issue. If not then I'll contact vaillant. Thanks again

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