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chineena

Comfortmaker furnace G-U 400100 -12m need wiring help

15 posts in this topic

Greetings;

I replaced the old Robertshaw Unitrol 7000 BER-1 24 volt gas valve with a White Rogers 36C03-333 and the relay terminals are different. The furnace wiring diagram is nowhere to be found. Can't seem to figure out how to connect the 2 black and 2 tan/white leads to the new valve.

Obviously, any help would be appreciated. I can post pics if needed.

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Need appliance parts? Call 877-803-7957 now!

Post some photos

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Sorry for the delay. Preparing for visitors.

I'm referring to the 2 black leads coming from the thermostat and the 2 marked with arrows (may not be on the correct screws) from the 24v power supply. All 4 of these were connected to the old gas valve. The black were piggy-backed but I separated them. I've attached a diagram that I made minus the 4 leads in question.

I'm referring to the 2 black leads coming from the limit switch - sorry.

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Thanks (I think) for the pdf but I can't install the executable on my Mac.

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Dummy me, I clicked on the big download button which I guess was an ad.

I actually have that manual. Still befuddled.

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Post a photo of your valve. I think you might have the wrong one. The terminals should have been the same.

Edited by applianceman18007260692

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can you draw a diagram on how the "old" Valve was connected ?

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More photos.

This furnace was installed in '85 so it's old. The Robertson Unitrol gas valve only had 2 terminals so the connections were simple. One black and the white to one terminal and the other black and the tan to the other terminal.

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can you draw a diagram on how the "old" Valve was connected ?

... into your hand drawn wiring diagram ?

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Here's the schematic with the old gas valve connected.

post-11390-0-53722400-1317240338_thumb.j

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use terminal TH and terminal TR

TH-TR is a spare terminal for other connections if needed

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One of them terminals don't do a thang like reg says. You won't get a reading between the dummy terminal and the other 2. So your 24 volts is goin to go between the 2 terminals that you get a reading from. Just in case you come across this again. Since you mentioned you had 3 terminals I wanted to be sure you didn't have a millivolt valve instead of a 24 volt valves. These valve come in a variety of different power ranges from line voltage ac to low voltage ac to millivolt.

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Excellent. You verified my suspicions. The middle terminal does nothing.

Thank you gentlemen.

And the cards win the wild card!

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