Tado Configuration

divemaster

I currently have an Ideal Logic+ System S15 gas boiler which has 3 outgoing copper pipes. one for hot water to a tank upstairs fitted with an immersion heater, filling of which is from the main water, one is for upstairs radiators and the third for downstairs radiators. I'm assuming this is classed as three zones(?). On each of these 3 pipes is fitted a Honeywell motorised valve which are all wired to an adjacent Horstmann 425 Diadem Programmer. Additionally, there is a wired Honeywell thermostat on the upstairs landing. I want to replace this setup with a Tado V3+ Wired Starter Kit and replace the landing thermostat with a Tado version. Depending on how this configuration works, I will likely fit Tado radiator valves to give greater control. Can anyone please advise if this will provide what I am hoping for before I purchase? Any assistance will be appreciated.

policywonk

According to this guide: logic-plus30s.pdf your boiler offers Opentherm. Look at page 31-34.

The Horsmann programmer seems to be an old-school basic 240v relay controller, not allowing you to use the boiler at full efficiency. The questions which now needs to be answered are these:

• Are those CH wired thermostats wired to drive the boiler, which then controls the motorised valves on the ground floor and first floor, or do they directly drive the two CH wired motorised valves?
• Is the relationship between the hot water tank's thermostat and the boiler direct, ie through opentherm, or is it operating the boiler in basic switched 240volts mode?

You will need to study the wiring centre near those motorised valves to clarify this. It may also need a call to Ideal, to clarify whether the boiler can be driven to turn on any, or all, of the motorised valves via a signal from the Opentherm side.

Page 34 strongly suggests it can work if you can get the wiring correct--- even the HW tank if you can get a honeywell opentherm thermostat to run the Hot water tank.

Please also contact Tado via the App and ask them specifically whether they support Opentherm on this model. There seems to be a contradiction based upon my search results. Dont work for Tado.

divemaster

Thank you for your response. Looks like I have to do some more checking with Ideal tomorrow when they open, plus some more tracking of cabling to and from the valves.
Thank you for your comment, very much appreciated.

policywonk

I dont have personal experience of Opentherm but there are lots of members who do. If you receive a shirty response from Tado technical support, come back here. Help is available.

divemaster

Thanks again policywonk for your comments. Since your previous reply, I've been digging around more and sent off questions to Tado, of which, I await a reply. In the meantime I have searched through many of the discussions on this site. Plenty to think about! I'll come back to you as soon as I get something from Tado.