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Strange (but probably okay) wiring between aquastat and burner control
I'm in the process of getting an inventory of all of my burner components for a much larger project I plan on undertaking. So step one is to figure out what components have what wires, and figure out where they go. In doing so, I noticed an odd configuration where I have an on/off switch labeled "boiler service" and it has 3 lines coming out of it. One is clearly the power in, then one goes to the Carlin 60200-02 boiler control, and the other to the Honewell L8124A,C Aquastat.
I thought that was odd since the Aquastat is supposed to power (or at least signal) the Boiler Control through the B1 & B2 connections, but there's no clear connection between the two devices, just this on-off switch. I opened the switch/box to take a look, and what appears to have been wired is the Red for the L1 of the Aquastat, and the Red for the Boiler Control have been spliced together at one end of the switch, and the other end has the red from power in (I get that that's clearly to shut power to the boiler off if need be). then the white wires for L2 on the Aquastat, the white wire to the Boiler Control, and the other Power in are all spliced together. Finally, the black wire runs from the Aquastat's B1 position to the Boiler Control.
I read through the schematics and installation manual for the Acquastat and I cannot find any reference to this kind of configuration, which makes me even more curious what's going on, but from the schematics it appears that those are roughly equivalent, and it of course seems to be working fine. So my real question is: Why would the original installer wire it this way instead of connecting (BC)Red to (Aquastat)B1, and (BC)White to (Acquastat)B2?