Central Heating wiring

[jengo883]

I am used to terminating combination boilers but I have never connected a Central heating 2port valve to a combination boiler.

The problem I have the Vokera Linea 735 combination boiler witch needs a dry set of contacts to trip the boiler. But I am unable to find a central heating programmer with two sets of dry contacts. Can any one recommend such a programmer?

The customer has a cylinder for hot water; the combination boiler is just for the kitchen sink.
In the summer they do not want the heating on only hot water. This is the reason for the 2 port valve?



Any help would be great.

 

[Agile]

I think that you need a three port valve or two two port valves otherwise how will you control the cylinder temperature.

You should not take on jobs if you dont have the necessary expertise.

Tony

 

[jengo883]

sorry guys volt free contacts

 

[jengo883]

Tony looking for help it would be good if we where all experts

 

[Nixt]

The customer has a cylinder for hot water; the combination boiler is just for the kitchen sink.

Tony looking for help it would be good if we where all experts

Thought help was for DIYers on this forum. If serving customers you're supposed to be an expert.

 

[bster]

use a three port and a twin channel programmer,Dont know how the switching works from voltfree boiler as the mid position will need 240 send and so will the cyl stat.

...come on guys enlighten the uneducated on voltfree y plans.

 

[EliteHeat]

Depending on your pipework arrangements you could use a 2-port, a 3-port or 2 * 2-ports. The key question is whether your combi can accomodate 230V switching. Glow Worms and Aristons certainly can not. If yours cannot then use a 2-port configuration - either 1 or 2.

 

[bster]

how come 2ports can handle the voltfree switching from the Gloworms (et al) then?

 

[EliteHeat]

how come 2ports can handle the voltfree switching from the Gloworms (et al) then?

Because they are volt free contacts (grey / orange)

 

[bster]

that makes sense then

I thought that the orange was the 240 to the boiler/pump

 

[bster]

iThink i've found the answer..


ts all down to the auxillary switch..yeah?



i love books!

 

[ChrisR]

Done it loads of times. Danfoss 975. Piece of p.

 

[Agile]

Mike, how can he do it with only ONE two port with both heating and a HW cylinder?

Tony

 

[bster]

So do you use a 2 port valve with or without auxillary switching or is theer a specific type (ie aux switching has nothing to do with it). and i know you get volt bfeee room stats but can you get volt free cyl stats (i presume you can).

I'm asking this as i'm doin a Sime combi and megaflow install in college soon (though the Sime may have 240 volt switching i'd like to know what to do on an install with a Gloworm boiler as we do these in work.).

 

[EliteHeat]

Mike, how can he do it with only ONE two port with both heating and a HW cylinder?

Tony

Oops, not possible.