How do I determine if a an AC's contactor is bad?
Does just the fan come on when you press in the contactor? Or does the fan and compressor start? And why are you manually pressing the contactor? Does it not pull in on its own when you initiate a call for cooling? If by pressing the contactor and the fan and compressor start, that tells us the compressor, fan, and capacitors are good. If the compressor does not start, then you may have a bad cap. or a bad compressor. Also check for burnt wires at the terminals. If the contactor will not pull in on a call for cooling, you need to check for 24 volts at the coil. Even though the contacts are pitted, current is still getting through because the fan is starting. Would not be a bad idea to replace it anyway. If you are getting 24 volts at the coil and the contact is not pulling in, replace the contactor. If you don't, check the low voltage wire to the condensing unit and make sure it is not broken. Make sure you have power at the furnace. Make sure the blower door is on securely. There could be a blown secondary fuse or a bad transformer on the furnace. Possibly even a bad thermostat. Some condensing units have low pressure cut outs which interrupt the low voltage circuit if refrigerant pressure is lost, so if it has one of these switches, it could be low on charge.
I have to depress the contactor manually to get the ac to run.?
You may have a couple things that could be causing you contactor to open. You may have a bad or intermittent signal to the contactor. If you have a High or Low-Pressure safety switch on this system, it will cause your contactor to dis-engage if you have a Low Vapor Pressure, or a High Head Pressure in the system. Clogged condenser coil on the unit (High Head) or low refrigerant charge / clogged air-filter on the indoor unit (Low Vapor). If you have had any varmints chewing on the thermostat wiring leading to the condensing unit, you may be getting an intermittent or bad connection to the contactor. Finally, there could even be a problem with the thermostat or the control board at your furnace or air-handler, or a connection issue with your low-voltage wiring to the outdoor unit, that comes from the furnace or air-handler.
Where is my ac contactor located?
It could be your contactor, but more than likely it is your capacitor. They are both in the outdoor unit. The contactor is usually black or brown and is right in front of you when you take the panel off the outdoor unit. Look for the big wires going into the unit. They lead to the bottom of the contactor. The capacitor is a silvery looking round piece found on the left side of the unit. You will usually have four wires coming out of the top. (1 for fan, 1 for compresser, 2 red for common). Turn on your AC. Go to the unit outside. Do you hear any humming noise at all? Good, then your contactor is working. Now check your capacitor.Does the top look like it is ready to explode? If so, that is your problem. Replace it with the proper MFD rated capacitor. If you do not hear a humming noise, even with the panel off, there are three things you can check: 1) Make sure the breaker is not flipped. 2) Make sure the disconnect is not pulled or went bad. The disconnect is the electrical cut off box located near the unit. 3) Check for any loose wires. If these check out OK, time to get a new contactor.
How do you test an AC contactor coil?
A magnetic contractor or starter is uniquely made to produce power to electric motors. It has an overload relay which is attached physically and electrically, and can detect motor overload which triggers it the supply voltage to open and start. It is a switch that’s run by electricity and is used to operate electric motors, lighting, heating and other items loaded with electricity. This are some tips which guide you in testing a magnetic contractor.Identify the L-side and T-side of the ContractorConnect the Wiring to the Volt OhmmeterObserve the TestElectricity travels in circuits, and in the heart of those circuits are magnetic contractors designed to keep everything running smoothly. But the system can jam from time to time. Although you should never try fixing problems that have something to do with electricity if you do not have the proper training and skills but troubleshooting a faulty contractor isn’t impossible. If you aren’t comfortable working with these components, hire a professional who can do the fixing for you. Ac Maintenance Clark Nj
My contact points on my outside unit are stuck open. What could be the problem?
I assume you are referring to the contactor for the outdoor unit. The contacts are closed when the contactor's coil is energized (normally with 24 volts) and it becomes an electromagnet. If your coil has an open winding or has a shorted winding it will not develop the magnetic field required to draw the contacts closed. If the control wiring to the contactor has been damaged, there will not be a pathway for the 24 volts to reach the coil. It is also possible your thermostat has a bad set of contacts in it. The 24 volts comes through a set of contacts in the thermostat. Coils can be replaced on contactors. Occasionally the contactor will fail mechanically, jamming so that it cannot close the contacts. It takes less time to replace the entire contactor than it does to replace the coil or the contacts. It is also usually a wise idea to replace the entire contactor rather than only parts of it. Most service technicians carry replacement contactors as part of their truck stock. They also often have replacement coils on the truck. The technician should be able to tell you exactly how much the replacement parts and labor will cost before any repairs are made. That way you can decide which way you want to go. I would recommend a new contactor altogether if its a bad contactor coil. Hope this helps.
What would cause a Contactor to burn in a 14 month old Goodman Air Conditioning unit?
The contactor coil is energized with 24V AC power. The 24V of control power is obtained from the transformer. Many transformers are designed for multiple primary voltages (120, 208, 230, and 460 are the most common). If the transformer is wired for 230V primary power but you only have 208V, the amperage being drawn will be more than the contactor coil can handle and the coil will burn out. If this condition lasts for some time, the coil's windings can be stressed from the excessive amperage and fail more quickly than normal. There are other things that could cause the problem, but I would think this to be the most likely cause. It will be necessary to check the primary power being supplied to the unit with a multimeter and make sure the transformer is in fact wired for the correct voltage. Unfortunately, transformers do sometimes burn out for no apparent reason and this may be the case with yours. Inserting a 3 amp fuse in the 24V circuit can help to prevent this from happening. The fuse will pop instead of the transformer windings burning out. The fuse will not prevent your having troubles, but the fuse will protect the more expensive parts from failing.
Why is there a capacitor connected in parallel with the coil of an AC contactor?
When the field collapses in an inductor/coil when power is cut-off suddenly, the change in field creates a voltage which opposes the current that created it and this is known as a kickback. This is usually very high(a spike) and is quite harmful to any circuitry that drives or controls it. The capacitor, usually connected in series with a resistor, (for time constant) provides an outlet for this spike to die down without harming the control circuit. It also acts as a spark quench circuit for the arching in the switching. For smaller voltages, a diode is also used across the coil.
My fan on my out side AC unit went out. Do you think my compressor burnt up?
It could be a burnt fan capacitor. $5 cheapest of many possibilities and common on hot days for this to fail. The fan will spin freely when power is off, and seize when powered on. The capacitor may look bulged from failure. The compressor would still run, and cycle on thermo overload. they are tough! I’ve seen units run days without a fan. A bad contactor $15 would prevent fan and compressor from running. Same for a burnt wire at the contactor.
Strange AC issue, contactor makes a clicking noise every minute but AC doesn't start.?
your thermostat tells the contactor when to pull the contactor in to start the compressor and fan. You need 25 v to do this. On the contactor it is the small wires tha attach to each side of the contactor where the winding is. Unplug the 240v at the disconnect outside and check for 25 v to the contactor windings. If you don't have a full 25 v I would look to see if there are breaks or loose connections between the wiring from the air handler to the outside unit. If that is fine test the transformer on the secondary side to see if you are putting out the 25 v needed. If you need more help contact me. Good luck
What are some reasons you AC might be running but not cooling?
Running can mean that the air circulation fan has started.Problems with the AC:Bad compressorLack of sufficient refrigerantUndersized design for the heat differential and flow load (not enough BTUs)Open windows, doors, lack of insulationFaulty thermostatBroken ductwork - clogged, leaking, fallen down or blockedClogged/dirty furnace filtersLow AC voltagetripped circuit breakerbad contactorbad starter motor for the fan or compressorthat's what I can think of in a 2 minute drill.