Viessmann 200W wireless thermostat connections

[juster]

Would like to use my old wireless thermostat on my new Viessmann 200W boiler until I sort out weather compensation.

Pics below show the wireless thermostat connections on the left and on the right the Viessmann boiler connections.

Any help greatly appreciated.

Wireless thermostat

• juster
• 27 Oct 2010
• 1

Viessmann boiler

• juster
• 27 Oct 2010
• 1

 

[D_Hailsham]

You use the LH stat diagram (Volt free)

Old Stat 1 connects to Viessmann 40/N
Old Stat 2 connects to Viessmann 40/L
Old stat 3 connects to Viessmann 96/L
Old Stat 4 connects to Viessmann 96/1

 

[juster]

Cheers mate thought it might be the same connections as the last boiler but needed to be sure.

 

[mysteryman]

You should draw the power from 96, not 40.

 

[D_Hailsham]

You should draw the power from 96, not 40.

Why? Wireless receivers need a permanent supply, which 40 gives as it is permanently live, unless turned off at the wall switch. 96 is controlled by the ON/OFF switch.

 

[juster]

Hey guys only used 96 L and 1 as I had wired the wireless receiver to a standard plug previously and not used live connections from the boiler.

Looks like I'm going to invest in weather comp controls sooner rather than later as I had a couple of incidents where the temp has been achieved on the wireless stat but the boilers still heating.

To get the boiler to turn off I've had to turn the wireless stat right up then back down again to a lower temp than displayed on the stat (cheap ebay crap lol)

If anyone can point me in the direction of Viessmann weather comp controls at a reasonable price I would be grateful as they seem to be in limited supply in the UK, and yes I Googled and double Googled.

 

[mysteryman]

Check if it is a 200-W type WB2B or a WB2C. The controls are different. You need a Vitotronic 200 type HO1 [white] or HO1A [black] respectively.