3 zones plus hot water

oxfordchap7

Hello,

I'm having trouble finding the right kit list.

I currently have a house with 3 floors. With a Vaillant Ecotec 624 boiler.

Each floor has a wired thermostat. There are 3 heating zones - one floor per zone.

I also have a hot water cylinder so I need hot water control.

After speaking with Tado sales, they recommended I ordered a wired v3+ starter kit plus 2 wired thermostats. But this doesn't do hot water control, which I was very clear I needed. So I now need to return the kit :(

I thought the v3+ kit was best because of the modulation factor. But I don't care so much about this - more interested in getting 3 zone control, even with the X. I also don't want to buy radiator controls, I just want to control the 3 zones with thermostats. Replace my existing system with one I control via app.

What is the best kit for me to purchase? That gives me control over 3 zones/thermostats, plus hot water programmer?

It's been frustrating so far.

Thank you for any help you can give!

oxfordchap7

Just to add, I'm not sure I can install myself. Happy to pay for an installer!

policywonk

Are there motorised valves opening heat to each floor, as well as the hot water tank, controlled by those thermostats?

oxfordchap7

Yes there are 4 motorised valves. So I assume 3x floors, 1x hot water cylinder.

oxfordchap7

I think these are 3 monitorized valves?

Plus the below for hot water?

policywonk

OK.

Thoughts so far.

1. I presume your boiler is actually a Vaillant Ecotec PLUS 624, a system boiler, whuch can be controlled digitally via the two BUS pins (+ and -) on the boiler's motherboard. This is the boiler's installation guide: 839592_02GB_032005_IAecoTEC.indd
2. It may help to print the guide, in particular pages 24-28. Your electrician will need it.
3. I believe you will need the following items to replace whatever is in place. You may need to confirm the exact kits with Tado.
   1. 1 x internet bridge
   2. 1 x Tado EU Extension Kit (aka wireless receiver)
   3. 3 x Tado wired thermostats - not 2.
4. Suggest you pass on all your configuration information you've given there to the Sales team and get them to forward exact instructions to wire your boiler with and motorised valves with their products. They will also confirm exactly what you need. If you have queries come back.
5. The remaining unknown for me is that box next to your hot water cylinder. Have not implemented the EBUS myself. I suspect that the Vaillant cylinder talks directly already to the boiler and ensures that the boiler's water temp is modulated. If in doubt, talk to Vaillant. If uncertain, your electrician will need to do that.

So onto the next steps:

1. Print the install guide for the boiler.
2. Identify through Valliant an electrician who can handle their EBUS wiring to:
   1. Fit the Tado products, wired to the motorised valve and to the boiler.
   2. Engage the EBUS feature on that cylinder
   3. Configure the boiler's settings
3. Contact Tado sales. Ask them to confirm the products you need (use this thread as the basis) and send you a complete installation guide for all this.
4. Appoint the electrician. Should take a morning. You might need to check on when the boiler is due for a service and have that sorted as well.
5. When it is fitted, you need to stop and think carefully over your daily schedules. You'll need to do this at least once a month over the next three months. Then you'll find your costs go down.

oxfordchap7

Gosh thank you! When I was talking to sales, I thought it would be more complex than simply switching a thermostat on the wall! I'll re-read this a couple of times.

oxfordchap7

Looking at this a bit more, I don't think it's possible based on what I read over here:

Vaillant VR65 with eBus and system boiler - hot water works but heating doesn't

autolycus

23 Sept 2022

Hi,

I've just installed a Vaillant EcoTech Pro 630 (system boiler with two zone valves and a vented HW tank) and have added a second-hand Vaillant VR65 wiring centre as I read on here that this is the way to make the V3 Extension Kit talk to the boiler via eBus.

Has anyone done this successfully and can you tell me how you wired it up please?

I've got the two eBus wires going from the Tado EK to the VR65 and then from there to the eBus connector on the boiler. I have removed the old 240V connection from the EK.

The two zone valves are wired into the VR65 using only live/neutral/earth and without the orange/grey wires that go to the zone valve microswitches. This is as per the wiring diagram for the VR65 (see attached image).

The HW stat is also connected to the VR65.

I have followed the Tado instructions to apply the Vaillant D07 eBus config to via the smart room stat.

When Tado calls for hot water, the boiler fires up as expected.

However, when there is a call for CH, nothing happens.

The only way I can get the CH to run is to apply a jumper link across the RT 24V pins shown in the attached photo of the boiler circuit board, or if I put a 240V live onto the lilac-coloured RT connector. But then the CH runs continuously and doesn't turn off when Tado tells it to.

Several people claim to have got Tado working with Vaillant system boilers over eBus using the VR65 unit, so any ideas on how to do it would be much appreciated please.

https://us.v-cdn.net/6031070/uploads/WFK37CGA78E9/boiler.jpg

https://us.v-cdn.net/6031070/uploads/HC4KEHC3FV5Z/wiring.jpg

https://us.v-cdn.net/6031070/uploads/34E29EAM5F5T/vr65.jpg

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From what I understand, I'd need a Vaillant VR65 module to enable proper eBus modulation with Tado. However, the Vaillant VR65 module only supports 2 heating zones, plus hot water.

This is all way above my head and now I'm thinking that perhaps I just want a simple way of controlling the 3 zones temperature, heat timings, and hot water timings, via relay (?) instead of modulation. And if I do this and ignore modulation, is the Tado X the way to go as it's the new version?

Thanks for your help.