After 4 visits from an installer, Tado still doesn't work

TMS_227

I have been building a holiday cottage in Northern Finland. Construction has recently been completely, and we temporarily moved in here. We've had our underfloor heating system professionally installed, but a year later we have not been able to get the Tado thermostats to work. Even after inviting the installers back over 4 times to look at the system.

We have a Panasonic T-CAP Kit Aquarea+. An outdoor air to water heat pump. An indoor unit with a boiler and accumulation tank. 

We have a Tado V3+ wired starter kit. 3 thermostats, one for each zone. 

No we were under the impression that Tado was not compatible with the Panasonic unit, so we opted to bypass the Panasonic completely and have our Tado thermostat control electronic actuators on the manifold.

Weirdly it seems like our installers have used multiple brands of actuators: 2 are by WATTS and the rest are from CANES.NO. However they are all 230V.

It also seems like they connected the thermostats directly to the actuators, as you can see in the photo.

As far as troubleshooting: we do have heating. If I change the temperature on the phone, the physical thermostat reflects the same change. However the temperature in the room never changes. Also if I change the temperature directly on the thermostat, nothing changes.

If I increase the heat directly on the Panasonic indoor unit, it gets warmer in the house. If I would set the temperature to 29 degrees on the Panasonic, that's how warm it would be, even if the thermostat is set to 20 degrees. That is what leads me to believe Tado is not actually affecting the position on the actuators.

As you might be able to tell I am not very knowledgable about this topic. But I would love to be able to call back our installers and tell them exactly what needs to happen to get the system working.

policywonk

The heat pump controls aren't initially the issue. Its all about how the actuators are powered and how the zone valves are assigned.

In my home, which has underfloor heating, a boiler and a conventional hot water tank, there are three two port zone valves.

• One turns on when the hot water tank calls for heat.
• The second turns on when the upstairs radiators call for heat.
• The third turns on when the underfloor heating makes it request.

Now this diagram is important.

Try and get that printed in A4 format so you can study it. Hopefully this acts as an explanation.

Your system should have a proper relay based wiring centre, not that little box with Wago's handling the whole show in one go. I cant fully see how the thermostats are wired but it seems as through they are all, together, switching all six heating loops. That doesnt make any sense.

Here's the logic. Your UFH manifold has a bundle of individual actuators, one for each heating loop. These normally run on either mains voltage, or 24 volts - and they should all be the same product.

Each actuator has a feed and return. What the wiring centre does is the following:

• if one thermostat calls for heat, it throws a relay for the relevant actuator, turning them on,
• and it ensures that the UFH pump is switched on
• and it ensures that the call for heat is also sent to your heat pump, via your Starter kit.

Or If more than one thermostat is calling for heat, the same principle applies and the system will run until all of them stop asking for heat.

Now, in a wiring centre, one thermostat can be set up to drive more than one actuator, but that thermostat does not have to deal with the switching burden for all the actuators - the wiring centre handles that with its relays.

The way I wired my underfloor heating, was to set WIRED thermostats around the house and run their cables to the wiring centre. In my case I had one thermostat drive 4 actuators, another drive 3, and a third drive one.

This is how you may want to proceed with the change:

1. First rig the wiring centre's relationship with the heat pump and Tado kit as described in that drawing. Can take about 45 mins.
2. Then individually wire each actuator into its own distinct channel in the wiring centre. Seems to take ages, it is fiddly but allow an hour.
3. Then sit back and map out on paper which thermostat controls which channel/UFH loop. May need 30 mins to draw it out and double check your thinking.
4. Then carefully find out which thermostat leads to which wire (that went into that small box). Do you have a multimeter, or electrical testing tools to double check?
5. Move the wiring runs to the wiring centre and stick to your map.
6. If a thermostat is meant to handle more than one channel, have the switched live feed piggy back onto the the switched live input on all the channels which must also be fired, so that when the thermostat first its switched live to ON, the relevant actuators are switched on. Do this slowly. Stop and double check.
7. Power up the whole system but first only allow one Tado Thermostat to call for heat.
   1. Then watch the impact on the UFH manifold, double checking that the right actuators turned on, that the heat pump is being fired, that the UFH pump is being fired, etc. Wait until it hits the right temperature and proves to you that the thermostat stops everything.
   2. Then turn that thermostat off, go to the next one and turn it on. Repeat until you are sure they are all doing the right thing.
   3. It should now all work. If you find that the call for heat in one group leads to a slower rise in temperature than another, then you need to note that and trim the relevant valves on the manifold. That can take weeks to get it right.
   4. Only when the UFH is working should you then check that the other side of the Tado service is working, ie hot water, etc. Keep the process simple at each step.

Note that your Tado starter kit can then decide whether it want to pump stuff into the storage tanks as well - and it controls the time things happen etc, via the zone valves.

I recommend the use of a Salus centre. There are others and they pretty much do the same job, ie use a relay to provide power to the relevant heating loop(s). I moved to Salus because I had to get rid of the plumbers and sparkies and fix the problem myself and found their diagrams and layout to be the most easy to follow.

The electrician who installs this wiring centre has to have enough experience with one of these wiring centres to make it work. Give him/her this drawing. If he doesn't understand it, find another electrician, or you could do this yourself.

Good luck. Am not a plumber or a sparkie. Am just a guy who had to fix a mess when he moved into each home.

TMS_227

Bless you! If only professional plumbers and electricians were willing to take the time like you. I will run this by them and see what they say.