Zone heating controls for Vaillant 837

[dextrous]

Have just had the 837 installed and it's currently running the house (3 bed semi) on one radiator circuit (2-pipe system), apart from a rad/towel warmer in the bathroom which I am shortly to upgrade and will thus install at a later date. I am competent to do wet pipework.

I want to have the bathroom rad as a separate zone to permit towels being dried/warmed during the summer whilst the remainder of the house rads are not on.

Can this be done through the use of a dual channel timer, using each channel to operate a two 2-port valves, each controlling a separate zone? Will obviously get my spark to do the wiring, but want to run a feasibility check by you all first.

 

[snb]

yes no problem with that set up

 

[dextrous]

Thanks snb. Had heard that vaillant combi/condenser boilers were sometimes problematic to separate into different heating zones, partly due to them requiring vaillant specific controllers, of which there aren't a significant number.

 

[mogget]

You can use the 837 with either Vaillants own controls, or ordinary s-plan type controls, but not both at the same time.

With all Vaillant controls removed, put 240v on terminal no. 4 and the boiler will burst into life as per normal.

 

[dextrous]

Thanks mogget - I bought the sit-in vaillant 140 dual channel controller at the point of installation anyway, which works fine, but currently only using one channel for the CH. Admittedly was a bit of a gamble at the time, but your responses so far indicate that it will pay off.

 

[gas4you]

The 140 won't work for what you are describing.

The second channel is designed for the built in HW pre-heat.

You will have to discard this and use an external independent programmer.

 

[dextrous]

The 140 won't work for what you are describing.

The second channel is designed for the built in HW pre-heat.

You will have to discard this and use an external independent programmer.

Have you one that you'd recommend based on experience?

 

[gas4you]

At present, if I can't use a manufacturers own programmers, I tend to fit Danfoss controls with a FP715 programmer.

I have never had any more problems with these than any other make and they are very cheap in complete kit form.

Honeywell seem to be the most popular on here and I fit their programmable room stats. They are very good, but more expensive.

 

[dextrous]

Thanks - your a star