New setup with solar

Hi All new here

My existing system Vaillant ecoTEC pro 2013 connected to Vaillant VCR 470 programmer.

I have had solar fitted this year along with a 200l hot water tank heated via a solar iboost.

The hot water tank is also connected to the flow and and return from the boiler via a motorised valve with the idea that when there is not enough solar to heat the water and the heating is on it will also heat the hot water tank.

The problem is my existing programmer use modulation so the hot water in the rads is not hot enough to heat the hot water tank.

After lots of research I decided to go for a system that doesn't use modulation I.E. Tado so I can set the water temperature manually and it will heat hot water tank.

After purchasing and installing my new Tado system I contacted Tado as I was unsure of where to connect cables in boiler only for them to inform me to connect cables to the X106 bus connection.

I pointed out to them the receiver is 240v powered and the bus connection is 24v surely there would be a conflict and I didn't want to fry the board.

They have since informed me I need to return the UK version and purchase the EU version but as I understand it uses modulation so it take back to my original problem.

I feel like I'm going around in circles with this problem.

Any help or advice greatly appreciated