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weston_clark

nest and furnace wiring mystery!!!

Weston Clark
3 years ago

we got a new nest this winter for our air conditioner. It worked great with the furnace but this summer it has been having problems. It is been showing delayed status a lot and turns on for just brief periods. looking online a lot of people suggest it needs a common wire. So, I thought I would try the hack. I swapped the green wire, the fan control, on both the best unit and my furnace. But the result was it said my common wire had no power. turns out my furnace wiring is not as simple as I'd hoped. I'm going to try and put a picture of this but anyone well-versed in wiring could probably help me out. I do know that this is attached to a humidifier as well as a water pump. the unit also has a thing called a Fast Stat 3000 that seems to be complicating the issue for me because it has all sorts of wires. I'm going to try and describe this from left to right on the wire connections onto the electrical panel of the furnace.

The w1 has a white and a red wire the white wire goes to the fast stat 3000 the red wire goes to a wire bundled with a white wire that is also connected to the common connection on the electrical panel.

there's nothing on W-2

the green wire goes to the fast stat 3000

there's nothing on y2

on y1 there is a yellow wire that goes to the fast stat and a red wire that goes to yet a large wire bundle that just utilizing a white and red wire. the white wire goes to the first common connection....

There are two common connections the first one has that white wire going to the large bundle. The second one has the white wire going to the first wire bundle I mentioned. it also has a black wire going to the fast stat 3000. finally there is a red wire coming out of the R connection. that goes to the fast stat.

The fast stat, other than those wires I've already mentioned, has a red wire and a purple wire coming from it. The purple wire connect to yet another bundle of a white and a red. It connects to the White.

The red wire from the fast stat connect to yet another bundle including a white and a red. it is connected to the red.

of these two last wire bundles I mention the white and red of those two bundles are connected together.

I guess my question is if I want to fulfil this hack and have a powered common wire up to my thermostat how do I do that? I have already tried just putting the green wire that goes into the fast at over to one of the common connections. actually, I've tried both. and it doesn't seem to work. help?

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