Have a general question. I know that the nest learning thermostat can accommodate two different 24 V transformers – for example, if your air-conditioning and heating system are separate and each have their own transformer.
however, I have a slightly different configuration: a legacy boiler/forced hot water, which I’d like to be the secondary heat source; and a mini split, which I’d like to be the primary heat source and AC (yes, there is an adapter, so the nest is not directly driving the mini split – don’t worry about efficiency, etc.).
The mini split adapter and the boiler, of course have different AC transformers.
Can the (cooling + primary heat) and (secondary heat) have different transformers? Ideally, I’d like the boiler to come on as secondary heat when it’s really cold or large temperature rise needed, but otherwise the mini split to do all the work. I can abandon the boiler or leave it on its own thermostat, but would be nice to have it available and controlled in one place.
