Hot Topics: AC In Wait Mode

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Original Post: "Wait" status on Honeywell for A/C

Sobjw Member

Not sure if this is the right section but I'm having an issue with my AC. It hasn't been used since the end of last summer and now when I try to turn it on my Honeywell 8000 series thermostat says "Wait" and it doesn't ever come on.

Heat works just fine as does the fan. Pulled the thermostat off the wall and the batteries were corroded. Replaced them with new batteries and reinstalled it and still getting the wait message.

Next step in troubleshooting? Thanks!

Getting proper voltage between the RC terminal and the others. Jumped RC to G and the fan kicked on, then jumped RC to Y and nothing happened (well a tiny bit of sparking but the compressor didn't turn on).

user 10 Member

You have to see if the outdoor unit is getting voltage between Y and C. shut disconnect off outside, leave air handler on, jumper R and Y at stat, then check.

What's the model number of the outdoor unit?

PJmax Group Moderator

Does it still say wait after 5 minutes of cooling demand ?

There is a 5 minute delay built in to many thermostats.

Sobjw Thread Starter

Yes, it says wait indefinitely. It hasn't been able to turn on at all. Haven't used it since the end of last summer. Getting good voltage everywhere and the compressor was replaced 3 years ago. The capacitor looked ok visually but it was getting sporadic readings on my multimeter so I just ordered a new one to see if that's the problem.

PJmax Group Moderator

Doubtful it's a capacitor problem. If it was, the unit would be sitting there and humming loudly.

Did you get 240vAC where the main power connects to the contactor?

Did you get 24vAC on the contactor coil?

Is the contactor closing?

“The Thermostat has built-in compressor protection (minimum off timer) that prevents the compressor from restarting too early after a shutdown. The minimum-off timer is activated after the compressor turns off. If there is a call during the minimum-off timer, the thermostat shows “Wait” in the display. When the minimum-off timer expires, “Cool On” appears solidly in the display and the compressor and fan turn on.”

This has me concerned. If your stat is staying in wait mode it cannot turn on the condenser or blower. Are you sure you are measuring the voltages that are needed?

Sobjw Thread Starter

Sorry for the delayed response. I've had three different visits from a local HVAC repair company.

First tech tested stuff for a while and said they needed to run a new wire from the furnace above the garage to the condenser unit outside.

Two guys came the next day and didn't even know what they were there to do (and forgot to bring their tools). I told them what the first tech told me and they proceeded to do the same troubleshooting steps he did. Then they told me I needed to run a new wire and left.

Third visit was the service manager, he did run the new wire but then he seemed to be getting flustered and said it wasn't the wiring, the contactor wasn't engaging and everything was wired wrong from when it was installed. He left and said he'd talk to the first tech. Waited a week, and then finally called them. The original tech said they recommend a whole new unit install because my system is so old it's not worth putting money into. $5,500.

I know there is a newer (three years) compressor out in the condenser unit. The house and unit are 20 years old, so not terribly old but also not that new. Definitely don't want to shell out that much money. Going to check YouTube and see if I can troubleshoot the contactor next.

PJmax Group Moderator

WOW. What a set of characters. I'm really disappointed in the current crop of service people. Not everyone can justify replacing a "should be working system" with a brand new system.

Do you have a meter? Do you know how to use it?

When checking on the contactor, the power to the condenser should be off.

Sobjw Thread Starter

Thank you for the help!

I do have a meter, not super great at using it but I can usually figure it out. I will check the contactor voltage later after I get home from work.

Sobjw Thread Starter

I am getting 237vAC where the main power is coming in, I assume that is close enough.

If I manually press in the contactor, the fan comes right on on the condenser.

I checked the low voltage connectors on the side of the contactor and am getting zero volts. I removed the wire nuts and checked the control wire coming from the furnace and still get nothing.

The original diagnosis was a bad control wire. The last set of guys did run a new wire (sloppily I might add) from the furnace up above the garage outside to the contactor. Seems like it's not hooked up correctly.

Sobjw Thread Starter

The contactor actually looks fairly new, I'm guessing they replaced it when the new compressor was installed three years ago.

PJmax Group Moderator

“When checking on the contactor...... the power to the condenser should be off.”

It's not going to be a problem with the high voltage. The contractor will close even if the high voltage is disconnected.

You are looking for 24vAC on the contactor coil. Probably missing.

Your thermostat demands cool and 24vAC comes out of the thermostat on the Y terminal. Usually that's a yellow wire. At the air handler, your condenser should connect to the C terminal or wire and the yellow wire from the stat. That's what you need to check with the meter.

Sobjw Thread Starter

So the yellow wire from the condenser connects to the yellow wire from the thermostat (Y terminal)

The blue wire from the condenser connects to the blue wire from the thermostat (C terminal) and a ground wire that is bolted to the body of the air handler. I've attached a photo of the wire nut connections and of the board itself if that is at all helpful.

Should I unscrew the wire nuts and put a probe on each wire and see if I'm getting voltage?

the colorful wires of an AC system

an AC circuit board with wires

wires plugged into an AC circuit board

Sobjw Thread Starter

Pulled the thermostat off the wall and am testing the terminals on that again and it isn't getting any voltage running to it.

Sobjw Thread Starter

Transformer has 120vAC going into it but nothing coming out, that would explain the dead board.

Sobjw Thread Starter

Removed the transformer, the 120v side is showing 1.0 resistance with the meter but OL on the low voltage side. Hoping to find a replacement tomorrow and install it.

Seems odd that the furnace and blower fan were working initially, only the condenser was originally failing to come on. Sounds like usually the wiring from the furnace to condenser is the problem but once that was replaced the whole transformer burned out. I'm a bit concerned there is something else going on here but maybe with the new wiring being run all will be ok.

Sobjw Thread Starter

Installed new transformer and the LED on the furnace board lit back up. Told the thermostat to call for cooling and nothing happened. LED not lit anymore after that.

Transformer is getting 120v in and outputting a sturdy 27v.

Fuse on the board was blown, tested the socket where the fuse goes and it was receiving the 27v just fine.