I pulled the old sensor out just to see what was behind there. It has a red and black wire (power, I assume) and a heavier red wire and green wire. I pulled the control panel above it out, and found a similar red and green wire pair. The meter says there is continuity from one end to the other of each wire, but I have no idea whether something else is connected behind the woodwork that I can't see. There are also red and black wires plus a yellow wire. The new sensor has only the red and black wires.
What are the red and green wires for? I assume that they are for the piezo buzzer. If I disconnect those wires from both the control box and the old sensor will that hurt anything, or will that buzzer screech forever?
I'm guessing that this whole system was OEM back in 1993. The new sensor says it should be replaced 60 months from the date of installation.
Interesting... on our U225 (also '93) I haven't found a CO monitor that looks OEM. There was a battery-powered combination smoke/CO sensor in the bedroom but nothing else. I'd rather have the battery powered types anyway (as long as I remember to change the batteries).
I have a second one I bought at a sale that I think I'll put up in the salon somewhere.
Craig
::) What about the tank solenoid interlock? Look at these colors first.
You should have 12v between 2 wires.
After my Sunday afternoon nap I had enough energy to pull the old sensor out and disconnect the red and green wires. I lit the stove, and it stayed lit, so I capped those two wires for now. Tomorrow I'll cut the hole to the right size, disconnect the power from the old sensor and hook up the new one.