DIY Home Improvement Forum banner
1 - 6 of 6 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter · #1 ·
I have a new 2 stage ASX180361a 18SEER 3 ton Amana AC unit, with a GMV950704C variable speed high efficiency furnace.

I am using a Honeywell TH8000 Series Programmable Thermostat.

If everthing is connected properlly, see below.

The question I have is how do you know if the AC unit is in the first or second stage of operation. Can you tell by using a clamp on amp meter while the unit starts up?
The installer said it needs to run for 20 minutes at a low temp setting. I set the ac for 65 and ran it for an hour. Current draw is 6 amps with the outside air at 88 degrees.
It started at 6 amps and stayed there.

Appreciate any help here.
 

·
Hvac Pro
Joined
·
23,688 Posts
Doesn't sound like your installer is too familiar with them. A true 2 stage thermostat will send an extra signal down the Y2 wire to initiate the second stage. A knowledgeable tech can test that at the outdoor unit with a meter. As it is new and under warranty he should make it work and have it wired properly also. There may also be a programming code/setting in the thermostat for it to be used as a 2 stage. By default most are set for 1 stage. Read the installation manual for more info.

Good Luck
 

·
Administrator
Joined
·
42,060 Posts
Set it 1° undr room temp. So it starts in first stage.

Wait till its running for about 10 minutes.
Then set stat down another 6 degrees or so.
You should hear the stat click, and the air flow from the registers should increase.
 

·
Registered
Joined
·
2 Posts
Discussion Starter · #4 ·
I tried it

I did what you suggested. Set it for 1 degree below house temp, Fan speed of the furnace went to 1000 rpm. Clamp on amp meter on the compressor reads 6 amps.
I then lowered the temp 10 degrees after 10 min of running on the above setting.
Thermostate clicked, fan sped went up to 1200 rpm.
The clamp on am meter stayed the same 6 amps.
So the blower in the furnanced ramped up, but the 2 stage compressor stayed the same no increase in noise level or increase in current draw.
 

·
Administrator
Joined
·
42,060 Posts
May not be wired correctly.

Call the contractor back.

Hard to say where its miswired at.
 
1 - 6 of 6 Posts
Top