Continuing work on the cabin. I picked up a couple wifi thermostats to replace the old mercury switch models so that I can monitor/control things when I'm not there. First issue was the existing wire was only two stranded so I pulled new wires. Now my issue seems to be connecting it to the Relay (which at this point I'm starting to think may not be possible). Current setup is an oil fired burner feeding a two zone hot water system, with a relay or what I'm calling a relay (see pictures) for each zone. One relay is a Honeywell RA89A, which doesn't have any place to connect a common wire. The other is a Honeywell Triple Aquastat (L8124A), which I can't seem to find much in the way of documentation on. So here's my question, what's the easiest way to get a 24v common that I can feed to the thermostats? Can I somehow connect to the "Triple Aquastat"? Should I add another transformer? Replace the Relays?