got it. i think the safest bet, electrically, is to use the same 24VAC adapter to power both controllers. depending on the rating of it, you may be able to get away with powering 2 solenoids simultaneously. the other option is to wire the 24vac adapters (transformers) in parallel to deliver the same 24VAC but at higher current capacity. e.g. if both are 24VAC rated @ 1A, and you wire in parallel, then you get 24VAC @ 2A, losses notwithstanding. then use this “big” transformer to power both controllers. but they have to be identical. so, safest is to use 1 adapter to power both. and then keep the commons were they belong; similar wiring as your 1st controller.