Replacing Danfoss TP5 with Vaillant VRT 360

[kon123]

Hi Guys

Newbie here, but learning a lot from this forum......its superb!

Looking at having our ancient Vaillant combi boiler replaced with a Vaillant EcoTEC Exclusive 838. Happy with the boiler but have a query about the room stat.

I currently have a Danfoss TP5 (battery powered, controlling timer and temp) located in the hallway, which appears to have 2 wires (I'm assuming live and neutral), which run to the boiler location. Is it possible to replace this current set-up with a VRT 360 or will it require a totally different set of wires and connections? The Vaillant website indicates I will need an e-bus connection but I have not got a clue what that is?

For various reasons, I am not keen to take up floorboards to run any additional wires from the VRT360 to the boiler location. I know Vaillant do a wireless VRT360 but I am just trying to keep costs down as much as possible!

By the way, it won't be me fitting it....so don't worry! Just looking for some advice so I know what I am talking about when the professionals come round!

 

[mickyg]

2 wires is all it needs, no worries

 

[kon123]

So the two wires I already have located there (red and black) will replace the '2 core bus cable' that the website says is needed?

If so, that will make things a lot easier!

 

[gas4you]

Make sure that the existing stat wires do actually run indepentently direct to your new boiler.

You don't want any voltage ending up on the ebus and blowing your new boiler pcb.

If any doubts go for the VRT360f wireless model for only a few pounds more, then you can change the mounting position if required.

 

[DP]

Two wires from TP5 will talk to boiler direct. These should not be any external voltages to TP5 except what it gets from terminals 3 and 4 (I think) on the connection strip on the boiler i.e. TP5 goes directly to boiler connections. Fails to see why one would want to remove the TP5

 

[simond]

Dave is referring to the induced current which can be present when significant lengths of mains cable are run in parallel with the VRT360 cable.

Thus the Vaillant recommendation to observe a cable separation distance.