Integrating Vaillant EcoTec 435 Plus Boiler with Boiler Stove.

[Walkergw6]

Hello Everyone,

I plan on integrating 30KW boiler stove with my central heating system. I have a Vaillant 435 EcoTec Plus system boiler (vented system) and Vaillant VR66 contoller and I intend to replace the copper immersion tank with a Gledhill Torrent vented 250L stainless steel heat storage cylinder and integrate a 30 KW boiler stove with the central heating system. I am looking for a way to prevent the boiler from firing when the boiler stove is maintaining the storage tank temperature. I cannot use a switch live for the boiler main power because the boiler is connected to a wireless room stat. If the boiler loses power the wireless room stat does automatically reconnect to the boiler and it takes ages to reconfigure the room stat to work with the boiler. Is there a way to send a signal (possibly via Ebus or other means) to prevent the boiler from firing when the cental heating water temperature is met by the boiler stove?

Thank you

 

[jj4091]

Electrically I think you could probably do it with an extra thermostat or a relay. But I also think you need someone who understands your system as there may be implications from the plumbing perspective and I am not a heating engineer. Scroll down to similar threads and there is a topic with a post that gives a circuit diagram which might help.

 

[Walkergw6]

Thanks for your reply. Yes, the plumbing system has to be redesigned to accommodate the integration of the system boiler with the boiler stove. I have worked with a plumber to design the plumbing system.

As for the electrical side of the system (having slept) I think I have found the answer to my query. The VR66 Controller has a normally closed thermostat circuit for monitoring the immersion tank temperature. When the tank temperature fall below a set point, the thermostat calls for heat from the boiler.

As I am replacing the Immersion tank with a Gledhill heat storage cylinder, I can add a N/C thermostat to the cylinder and connect it in circuit with boiler stove (pipe thermostat) so that only one thermostat has control at a time while de-energising the alternate circuit.