@BillyDaDad: if you need to use wireless sensors, you can power them separately with a 24VAC transformer. This is not ideal (i.e. having two transformers), but should work just fine. In fact, I am fairly confident these wireless sensors would work fine with 9VDC too. I’ve personally taken apart some of these sensors and it looks like the internal power circuit just consists of a rectification part followed by zener diode for voltage regulation. If so, there is no reason why they can’t be powered by 9VDC instead. Of course this isn’t ideal either, because the 9VDC power supply uses a plug type connector instead of the 24VAC adapter that exposes bare wires. In any case, the separate power supply option is always available.