Without it, the AC system will not be able to circulate any heated or cooled air. The blower motor relay controls the current used to power the blower motor, and is subject to the constant on and off switching.

Over time, it can eventually wear out. When the blower motor relay does begin to fail, the vehicle will usually display a few symptoms that alert the driver of a potential problem that should be serviced. One of the first symptoms of a problem with the blower motor relay is a blower motor that does not function at all. As the relay is the switch that supplies current to the blower motor, if it fails internally, then power will be cut off from the blower motor circuit, causing the motor to no longer function or blow any air from the vents.

One of the first symptoms of a bad or failing AC blower motor relay is a blown AC blower motor relay circuit fuse. If the blower motor relay develops any sort of problem that hinders its ability to properly limit and distribute power, it may cause the blower motor fuse to blow.

Any sort of electrical spikes or excessive current from a bad relay will blow the fuse and cut power in order to protect the system. Another more serious symptom of a problem with the blower motor relay is a burned or melted relay.

Relays are exposed to high current loads and can sometimes get hot when they develop problems. In serious cases, the relays may heat up to the point where the interior components and plastic housing of the relay will begin to melt and burn - sometimes even causing damage to the fuse box or panel as well.

Since the blower motor relay is essentially the switch that directly controls power to the blower motor, the entire AC system will be left unable to distribute its cooled or heated air if the relay fails. They will be able to determine if the car will need a blower motor relay replacementor a different repairto bring full functionality back to your AC system. The most popular service booked by readers of this article is Heating AC Inspection.

Our certified mobile mechanics make house calls in over 2, U. Fast, free online quotes for your car repair. Schedule Heating AC Inspection. Service Area. Average rating from 54 customers who received a Heating AC Inspection. Blower motor does not function One of the first symptoms of a problem with the blower motor relay is a blower motor that does not function at all.The temperature in my house is 79F. Thermostat is set to 74F. The outdoor AC compressor unit is constantly running but the indoor blower fan keeps stopping.

It's running for 2 minutes, turns off for another 2, then turns on again. Could the motor be overworked and overheating? Any way I could check for this? This could be a thermostat issue or a fan motor issue. That fan motor is controlled by a fan relay on a fan control board.

If that winding is overheating, you can tell easy enough. Find the fan control board. Now see if the fan stops and starts. If it doesn't its the fan motor. The poster above is confused. Air conditioning fan blowers are v. This is a question not an answer. Today the indoor temp was I set the t-stat to I shut the unit off. If I leave it off for a time and restart it it starts up and as long as it is cycling to 2 degrees of the set point it is fine.

Other than that anything that will cause a long run results in the blower motor stopping and the compressor still running. It is some sort of cut-off either related to temperature, a bad motor or a bad relay on the control circuit board that overheats and opens. If you have experience with high voltage circuit analysis and testing, you can follow the diagnosis thread below, else, please stop and call an experienced, honest tech to fix this issue.

Assuming experience with V, you can diagnose this a bit further by checking for the presence of V on the blower motor terminals at the circuit board when the motor is in its OFF state. Look for the terminal marked "Cool" and it should have the Black wire from the blower high speed or the Yellow wire medium high connected to the Cool terminal. If there is V present at the terminal and the fan is OFF, then your problem is not the circuit board.

Now you have to determine if it is the motor or a temperature cut-off at the motor or the capacitor somehow shutting off the motor. To diagnose further, you will need to remove the motor along with the blower wheel as a single unit two screws hold it in the furnace cage and test further and repair accordingly. If V is not present when the fan is OFF, then you have a circuit board issue.

blower motor runs then stops

To diagnose further, disconnect the blower fan connections and trace back on the board till you find the fault, often repaired by a relay replacement. But that requires testing with a live circuit. Use extreme caution - you are working with V. If motor was getting hot it would take more than two minutes to cool off.

Jump out green and red on control low voltage wires by furnace. If it persist then if would rule out the stat. If in furnace you can hard wire the blower to get you through till you get it fixed but you have to know what you are doing or you may burn up the motor. Better to just turn everything off and wait for tech as not to damage any thing else.

Your blower motor is overheating and the bearings may be ceized if this keeps occuring, the way to tell would be to check the motor inside the furnace and see if its hot to touch, if so the blower motor will have to be replaced.User Name Remember Me? It blows strong and warm. After sometimes just a few seconds it will slow down and eventually not blow at all.

I am leaning toward Resistor issue, but figured i would post to get everyones opinion. A search only found many poeple that had an issue with no speed on anything but 4, but this is not the same. I have the correct fan speed and whichever I select, but it only work for however long it wants to, usually under 3min.

If I switch it back to zero for a few minutes and then back to any speed it will work again for a few seconds to a minute. Thanks -Justin. Williamsville, NY Sounds like you may need a new blower motor. Either the brushes are worn down or the bearings need to be lubricated.

Thanks Steve. TDI s : Jetta 5spd. I agree with Steve. I just had to replace my blower motor last summer and was doing just what you described. I chose "A" Typical failure mode.

Not that unusual for that many miles. Thanks, guys. I'm gonna go grab one today. Wish it wasn't 20 degrees out though. Oddly, similar problem.

blower motor runs then stops

Two days ago, sunny, 15 degrees Celsius, hot in the car, tried the AC in my Jetta withkm for a few minutes. I shut off the AC then put the blower on max and noticed it slow to a complete stop. I put the switch to off. After waiting a minute, the fan would blow hard, then slow to a stop again. I removed the fan assy and ran it for an hour on a battery charger with no problems. It is a bit stiff to turn but I would hate to buy another one only to find it was something else.

Why would it do this in the car and not in my basement? Last edited by Looney2uner; May 9th, at Reason: spelling. In the car it is near active heat sources. It may also be due to the power source. In the car you are running it through wires that you are not using when it is out of the car.

There may be a high resistance connection somewhere. However my guess is still the a resistor or the resistor pack.

blower motor runs then stops

If it were my car I would have replaced the resistor pack long ago and have been done with it. A resistor pack is an assembly with several resistors to control various speeds. One speed may go out and, depending on the car, you will need to replace one or more resistors or you may need to replace the pack as the individual resistors may not be serviceable. Engine heat, high resistance between battery and the motor somewhere. The problems you are experiencing are common.A gas-powered leaf blower uses a combustion engine to generate power.

Normally, when this engine burns gas, the vapors and heated gases are vented away, so the engine can stay cool enough to keep running. If the engine dies after warming up, it is likely the engine is overheating and automatically shutting down to prevent more serious damage.

Vapor lock occurs when the fuel already inside the carburetor overheats and the vapors cause the fuel pump to lock up. A vent on the gas cap allows those heated gases to escape, which prevents the fuel inside the tank and in the fuel system from overheating. To check for vapor lock, after the engine shuts down again, unscrew the gas cap slightly and try starting the engine again. If it runs without shutting off again, vapor lock is causing the problem.

Replace the gas cap, or clean it thoroughly with a brush dipped in fresh gasoline. As the engine starts moving, the internal temperatures also start rising. To keep the engine running, cooler air needs to be brought in, and the heated gases need to escape. If the air filter or muffler are blocked, the engine will overheat and shut off again. Take out the air filter and wash it in soapy water. Clean the spark arrestor screen inside the muffler, and scrub out the muffler and exhaust port with a brush.

Brush off the fins around the cylinder. The carburetor inside a leaf blower uses several plastic diaphragms to bring fuel into the carburetor, mix and measure the fuel and send it off to the cylinder.

These diaphragms can warp after several seasons of use. This warping will cause the fuel to stop moving through the entire circuit, and the engine will shut off. Usually this happens when the engine starts heating up, as the diaphragms aren't completely shot yet, but are starting to go. Remove, disassemble and clean the carburetor. Check for any perforations in the diaphragm and gaskets. If the engine is dying in rough fits and shakes, and the starter rope is hard to pull out after the engine dies, the likely cause of the problem is inside the cylinder.

If air is entering the cylinder from a leak around the seals, the result is a loss of compression. This compression is required to keep the piston and crankcase moving, and, without it, the engine can't start. Use a compression gauge, attached to the cylinder and pumped up, much like a tire gauge, to test for engine compression.

If the compression reading drops off rapidly, take the leaf blower to a mechanic. Currently based in Minneapolis, Minn.

$25 Echo PB500T Backpack Blower that Dies Under Load HOW TO FIX IN LESS THAN 2 MINS

He holds a Bachelor of Arts in creative writing from the University of Montana. Hunker may earn compensation through affiliate links in this story.By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service.

It only takes a minute to sign up. I have been having issues with the AC portion the furnace heat seems to work fine. The AC will start out the day working great! Cold air blows out it will run for an hour or two and before it gets to temp the blower motor shuts off while the compressor continues to run.

Then at this point the evaporator coils tend to freeze sometimes. Then, the blower motor seems to try to run every 10 minutes or so. The blower spins up, runs at a low speed for a few seconds, and turn off again. Eventually, after many attempts the blower fan will kick on and the AC will begin to cool again then rinse and repeat all day.

Also a strange and likely connected issue is that I cannot turn the blower fan on from the thermostat I turn it on from the thermostat and nothing happens. Cooling is adequate on most days with this issue when the outside temperatures are F but when it's hotter outside above 85F the AC can't keep up and it never gets colder than 80F inside. Sign up to join this community.

The best answers are voted up and rise to the top. Home Questions Tags Users Unanswered. Furnace blower motor runs briefly then turns off Ask Question. Asked 2 years, 9 months ago.

Active 2 years, 2 months ago. Viewed 12k times. I can power cycle the whole unit but doesn't seem to fix anything. Troubleshooting steps I've taken: Multiple google searches. The issue seems to be unique to my case.

Cleaned my evaporator coils and compressor coils.

blower motor runs then stops

They were pretty dirty and neglected but issue continues even though now they are squeaky clean. Full wires check. Checked AC sender wires, thermostat and thermostat on the furnace side. Removal of 'saver switch' my electric utility company added a saver switch that turns off the compressor during peak times of the day. I have bypassed this. Hardwired the blower fan. Tried to direct wire the blower by crossing the green and red thermostat wires.If the engine on your blower runs then dies, you might need to check the tank vent, ignition coil, or gas cap.

Our repair guide can help you identify your problem and show you how to fix it with the right part. Shopping Cart. Submit Search.

How to Repair an Electric Motor That Turns Slow

Sign in Sign in with Password. Cart Shopping Cart 0 item s in your cart. Restore a saved shopping cart. We're open and continuing to ship packages. Blower: Runs For A While Then Dies If the engine on your blower runs then dies, you might need to check the tank vent, ignition coil, or gas cap. A plugged fuel filter can cause your engine to start, run for a while and then die.

The fuel filter on your leaf blower connects to the fuel line, and filters out any debris that may be in the fuel tank. Over time, this debris can build up in the filter and make it more difficult for fuel to enter the lines and ultimately get to the engine. If the obstruction is minor, the engine will run for a little while before dying, rather than almost immediately after the engine starts.

To fix the issue, you may be able to clean your fuel filter, but if it is faulty or damaged it will need to be replaced. Find your Fuel Filters here.

A bad spark plug can cause the engine to die at any time. When your leaf blower is running properly, the spark plug will ignite compressed fuel and air with every rotation of the piston within the cylinder. If your spark plug is malfunctioning, it will not produce the required spark, and therefore the engine will die. As mentioned, if your spark plug is faulty, this can happen to your engine at any time. Find your Spark Plugs here.

A vented gas cap can cause this problem. If the vent is plugged, a vacuum will form as the fuel level drops. To solve this problem, you can allow the engine to sit for a short period of time, or you can remove and replace the gas cap.

After you apply one of these solutions, the engine should start again. Find your Caps here. The fuel lines on your blower carry fuel from the tank to the engine. You may be able to clean out the fuel lines and solve this problem.InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website. Some conditions that cause unexpected furnace fan operation may be dangerous, risking overheating of the furnace heat exchanger which in turn risks cracks and even carbon monoxide leaks.

So it is worth checking out this problem promptly. The burners fired up, went through the cycle and cut off just as it should. I reattached the fan, the system kicked in and the fan came on. The furnace ran for about 20 minutes, burners cycled on and off normally, but then the system shut down before satisfying the desired temperature.

The burner will stay on and the blower will continue to run on most forced warm air heating systems until the room thermostat is satisfied. At that point the burner turns off; the blower continues to run for a brief time to cool down the heat exchanger and supply plenum. Watch out : locating a return air inlet close to a heating furnace, particularly a gas or oil fired heater may be unsafe - as shown in our photo above.

Why Does My Furnace Blower Turn On and Off Constantly?

Watch out : If your heating system is shutting down before the room thermostat has been satisfied, the system may be unsafe. We don't want to overheat the heat exchanger or supply plenum - doing so can crack the steel, resulting in potentially fatal carbon monoxide poisoning of building occupants.

Howard make sure you are considering the right "temperatures" and fan connections? The set temperature at the room thermostat is the desired room temperature. As long as the room temp is below the set temperature, with a slight technical exception around the heat anticipator circuit the thermostat will continue to call for heat.

On a call for heat on most warm air heating systems, the furnace heater turns on, the supply air plenum air heats up, the then the blower assembly runs and will often continue to run until the call for heat is satisfied.

But in some cases, such as blocked airflow due to a dirty air filter, the supply plenum could reach an abnormally high temperature and the fan limit switch will then shut off the burner for safety. Watch out : overheating the heat exchanger is dangerous. If this is going on your furnace should be checked by a professional. My furnace turns off at 20C even thermostat is set to max 35C. New thermostat was installed I have looked and monitor the fan limit switch.

Just wondering if there is something wrong with Fan Limit Switch and how do I reset the Fan limit switch. So in normal operation the furnace plenum temperature will reach the OFF limit and turn off the burner. The blower assembly will continue normally until the plenum has cooled down. It sounds as if your furnace is working normally. We have a Clare Hecla forced-air gas furnace with air conditioner.