Rheem RHC-TST412 Thermostat hookup

[dakotatech]

I recently had a Rheem RGFE Mod furnace and AC installed. The heat portion works extremely well and now it's time to start the AC. Before I do I would like to verify the thermostat was hooked up correctly. The installer did a good job installing the unit but the thermostat was a something he had never installed before of it was a bit of a challenge.

If it's not correct, I would like to have them come back out and correct it before I start it up. A picture of the furnace and thermostat wiring it attached

Furnace : RGFE07
Outdoor unit : RAPM-024JAZ
Thermostat : RHC-TST412

Thanks

[Rob_in_WV]

at a quick glace it looks correct. The best thing to do now is turn it on and see if the a/c kicks on and runs.

[dandyme]

two separate pics wouldn't have confused me near as much:gah::grin2:

[dakotatech]

I started it and it's running. The compressor seams a little noisy but I'm not sure.

The only confusing part so far is the stat shows "System On +2" which notes a second stage. I'm confused because this is only a single stage AC. This was part of my question I forgot to ask originally.

I was confused between Y and Y2.

I'll have to call the installer and have them stop and just take a look and listen.

Thanks

[Rob_in_WV]

"Y" is first stage cooling and "Y2" is second stage cooling. sounds like he might have accidentally programed it for a 2 cool system and needs to come back and tweak the settings.

[BaldLoonie]

It comes factory as 2 stage. Can be changed but doesn't hurt anything as it is other than saying +2 which does nothing.

BUT, I'm not sure hooking yellow to Y1 is giving you full airflow. Usually Y1 gets about 70% airflow for a 2 stage A/C. That's the way it is on the RGFD anyway. But it labels the other terminal as Y/Y2. Couldn't see the answer in the instructions since the 412 was really designed for the non communicating furnace though it works on the RGFE. May have to hook to Y2 or jump Y1 to Y2. Better have your dealer look into that or you could be hurting for airflow. Past my bedtime, I'm not alert enough to figure it out :D

[dakotatech]

I'm going to give the installer a call. The fan was running on low with a "Cd" code on the furnace display. I was confused as the humidity was set to 56 but the actual was like 41. The plenum was very cold and starting to form condensation so I think there may be an airflow issue.

I know I don't have the best thermostat for the setup. When I did the research (and I did a lot) everything said to use the 412. This is also what the distributor delivered.

When the installer tried to hook it up he had a heck of a time. He had never seen one and I was just internet educated so after a number of hours I ran a new thermostat wire (8 wire instead of 4) for them and they got it working. Of course while trying to get it all to working he tried to tell me the distributor told him I really should have the 501.

In the end we were both clueless and a bit stubborn. After I had figured it out of course then they were happy to come out and install the 501 if I paid for the stat and labor. For $400 plus I was happy with the one I had as it runs heat very well.

In the end I should have installed a basic everyday system they install and I probably would have been just as well of.

I really do like the mod furnace however as it's as quit as a mouse when it runs.

Thanks for the help.

[BaldLoonie]

It's in dehumidify mode or slower than normal fan speed. They better look.

[dakotatech]

Update on this. The tech came out yesterday and performed the following. Before he did I took more pictures of the dip switches so I knew what changed.

1). Added a jumper from Y1 to Y2.
2). Set dip switch sw1-1 to "on" and sw1-2 to "off" (reversed them)

From what I read in the manual the dip switch change will slow the airflow.

From what I see on the 7 seg display blink the fan speed is now running at 800CFM which is probably correct as I think it was closer to 400 before but I'm not sure. The display still shows "Cd".

As far the as the compressor vibration he said this was because the compressor was not under load do to the outside temperature only being 70. He said when the compressor is under load at a higher temp it will quit down.

Now if I can just get a hot day to try it out.

Thanks for everyone's help.