Replacing Hive with SensoComfort Vaillant Controls (EcoTec Plus Boiler)

[Deleted User 298457]

Hi folks,

Just received my new weather-compensating thermostat and receiver. It seems it is designed for the newer Vaillant boilers so I'm not sure if I am stuck here (i.e. it has a 4 pin connector that on the newer EcoTecs would just click in/plug in.

Is it even possible on this boiler? It requires EBUS.

Pics:

 

[oggiet]

Show inside of your boiler where ebus is. That's where I connected mine.

 

[Dangerous Dave]

Was it the wireless version you bought (720F) ? On the newer boilers it has an external socket and attaches to underside of the boiler, on the older boilers mount the receiver externally on the wall and connect to the internal boiler ebus connection with a cable, you will need a Vaillant wiring centre to connect the zone valves and either mount the supplied temp probe in your cylinder or use the current thermostat to trigger when it is satisfied.

With the Vaillant wiring centre you run permanent 240v to the boiler and wiring centre and daisy chain the ebus connection to the receiver/wiring centre.

*edit to remove a question around the permanent feed to the boiler can now see it's a 5 core cable to the boiler couldn't quite make out the neutral.

 

[Deleted User 298457]

Show inside of your boiler where ebus is. That's where I connected mine.

Ah is it inside on this model? Gotcha.

Was it the wireless version you bought (720F) ? On the newer boilers it has an external socket and attaches to underside of the boiler, on the older boilers mount the receiver externally on the wall and connect to the internal boiler ebus connection with a cable, you will need a Vaillant wiring centre to connect the zone valves and either mount the supplied temp probe in your cylinder or use the current thermostat to trigger when it is satisfied.

I might not be seeing a perminant supply to the boiler but does your boiler totally power off when there is no demand for heating/hot water ? If so it's miss wired it should have a permanent supply to allow the pump overrun to run once the demand for heat is satisfied and a separate feed to active the boiler for a heat demand (you'll sort this if you switch over to Vaillant controls).

With the Vaillant wiring centre you run permanent 240v to the boiler and wiring centre and daisy chain the ebus connection to the receiver/wiring centre. If it does totally power off when no demand there will be a bridge wire on the 240v control in the boiler you'll need to remove.

Super helpful thank you. Yes it is the wireless version. I also want the internet gateway too, which I've heard you can just double up the wires on.

The boiler doesn't power off ever, so it must be permanently live. I was hoping a quick swap in/out -- is the Vaillant wiring center easy enough for an idiot to do? I don't have to touch any wet bits do I? (3 way valve etc).

Edit: Damn, the wiring center is big dollar. I think I might be about to give up on this project!

 

[Dangerous Dave]

If you only have one zone and hot water cylinder a VF66/2 should cover it and not that pricey should be under £100.

*worth double checking that works with the 720F looks like it does but Vaillant can confirm.

It is easy to wire up simpler than the wiring centre you have now, you don't wire the trigger switch in the valves so it's just the positive plus neutral from the valves into the heating/hotwater connections. The tank stat or temperature sensor for the hot water cylinder and the 240 power/ebus.

 

[Deleted User 298457]

If you only have one zone and hot water cylinder a VF66/2 should cover it and not that pricey should be under £100.

*worth double checking that works with the 720F looks like it does but Vaillant can confirm.

It is easy to wire up simpler than the wiring centre you have now, you don't wire the trigger switch in the valves so it's just the positive plus neutral from the valves into the heating/hotwater connections. The tank stat or temperature sensor for the hot water cylinder and the 240 power/ebus.

I've all but bottled this project - DX are scheduled to collect at 3pm. One final hurrah that may change my mind - if you know - am I just short a VR70/VR71/VF66/2 wiring center to get this functional? Or am I expecting to touch the wet bits?

I have a Kingspan tank so no idea about thermostat or hotwater connections.