Outdoor ac compressor does not turn on?
Here's what's happening and what I've tried. Looking for Chief Many Crows response...:)
The indoor unit does turn on.
Replaced capacitor and contactor on outdoor unit (Bryant unit & does not have any circuit board)
Verified 220 power to unit is good. Also verified 24 volt is good to the contactor and capacitor.
I can manually push in plunger on contactor and the compressor and fan turn on.
Honeywell thermostat is only 1yr old so should be working fine.
Could there be an open ("short") in the line after the capacitor that is keeping the system from turning on?
Help:)
Comments
You've gotten some good answers, and there's nothing I can really add; except this: The first answer is on the right track. If the contactor can be manually pushed in AND the compressor starts you've verified that the compressor is not the problem.
You also stated that the 24 v to the contactor is good; I'll assume you checked it with a VOM or DVM (Volt Ohm Meter or Digital Volt Meter). Having clarified that you DO have 24 volts at the coil (contactor) but the contactor is not clamping, remove all power, disconnect the contactor control wires (low voltage line) and check for resistance between the two wires coming from the contactor. You should have some measurable resistance. If you are getting an open circuit then the coil has opened, and will likely need to be replaced.
Before you do any repairs you might want to surf the net and see if other people are having the same problem you are having. If so, it could be a bad design. You might want to think about modifying and upgrading to a more reliable contactor assembly.
Good luck.
")
ADDITIONAL: I see that seven months ago you were having issues with your AC. Well, I'm wondering if it might be just that, a badly designed system. It could be the cause of the manufacturer OR it could be the company that installed your uint.
I've been considering central air for my home in Utah. Currently we rely on an evaporative cooler because the climate is typically dry. EC's work well because of the evaporative cooling effect that occurs when water evaporates.
However, looking into the situation, I've had several contractors tell me I need a one ton unit, a two ton unit and a three ton unit. When I looked into it further, using an under rated unit will mean it has to work harder. Hence, burn out (or fail) more quickly. You might have a unit that is under rated for your purpose. Just for fun I would now recommend you get some quotes on a replacement unit. Pay attention to what size unit they say you need as compared to the size of the unit you now have. If they're saying you need a bigger unit then you might conclude that the current unit may continue to give you trouble. However, if they say your current unit is big enough - just be advised to keep an eye on how well it works. You may in the long run end up replacing it.
Bryant is not known for having a poor product, but I also know that they are manufactured on the same assembly line as Carrier, Day & Night, and Payne - as well as some more recent units they have purchased and incorporated into their lines. So I don't think your Bryant is the problem, I suspect it may be under rated for your house size.
Again, good luck.
")
First, I have to say, if you are not trained and comforatble working safely with electricity, DO NOTHING that I am about to mention. touch the wrong energized wire while you're grounded, and you'll be in a hospital bed or a pine box..... that said, I am a little put off by what you have verified so far, since there should not be 24V going to any capacitors. contactor? yes. Capacitor? no....start by removing the face of the thermostat, and writing down what wire color is attached to what terminal. (Usually red is on "R" White is on "W" Green is on "G" and Yellow or blue is on "Y") the point is, whatever wire is attached to "Y" is the wire that the thermostat uses to call the furnace and tell it to cool. once you have your wires Identified, put the thermostat back together, set it for cooling and go to the furnace. before you do anything else, READ the beginning of this answer again. Read it again..... one more time now......... okay. DO NOT TOUCH YOUR FURNACE unless you know how to keep yourself safe around electricity.... we good? good. I'm not saying this as a legal disclaimer, I'm saying it because I REALLY don't want anyone getting hurt because They saw my advice and thought they'd just "figure it out" it takes a SPLIT second to get into a situation you do not want to be in. IF you KNOW how to stay safe, then get into the furnace and find the thermostat wiring. with your meter, touch one lead to the wire that is coming from "Y" (use the chart you made when you looked at the thermostat) touch the other lead to the common side of the transformer, or if it's easier for you, any bare sheet metal on the furnace. If there's power coming to the furnace (press in the door switch) and the thermostat is calling for a/c, you should read around about 24V. If this is true, the next step is to find the wires coming in from the outside unit, trace them back to the furnace, and check to be sure that ONE of these is attached to the wire you were just fiddling with (The "Y" wire) the other should be attached to the common side of the control transformer. If there are more than 2 wires in the sheath, make sure that you have one on "Y" and one on common, and write down which colors are the 2 you have attached. go outside, go to the unit, and at the contactor, check to see that the 2 wires you have attached are the two attached to it. place one meter lead on the terminal of each wire. If you get 24V and the contactor isn't closing, the contactor is the problem. if you don't get 24V, you will need to trace the 2 wires from the a/c unit all the way back to the furnace. look at every inch, and figure out if it's chewed, frayed, or broken in any way. if so, fix it. if you still have problems, post it, and I will try to think of other options
If you can manually push the contactor in and the compressor starts then that determines that your compressor and power are good. If you also have verified that you actually have 24 volts going to the contactor coil and it is not pulling in, then it is obvious that the coil in your contactor has fried. You will have to replace the coil, if it is of the replaceable style, or the entire contactor.
Although I agree with the other first response, I would have a look at a couple other things.
First, the T-Stat itself. If it is a new digital one, swap it out with another older analog one known to work, or failing that, another model T-Stat from a different manufacturer. These electronic marvels are sometimes the fault.
The second is based on an experience. I recall mice chewing through a T-Stat wire from the furnace control board to the outside condenser unit right at the junction where the control wire exited the house.
While on the subject, be sure the wall T-Stat is wired correctly (most likely is but check anyway) and the terminals are tight.