Ruud ubha-21j00nuaa It is 87* outside and my house stopped cooling. I checked the condenser unit outside and the fan was running ok so I went up in attic and checked air handler and found all the coils frozen. I last changed air handler filter and all return filters 3 weeks ago. what could be problem?

SOURCE: Air Conditioning

Open the access panel on the air handler in the attic and take a look at the evaporator coil. If you have no airflow, and you just changed the air filter, then you probably have a buildup of airborne crud on the coil that's blocking airflow. If you do have a layer of buildup blocking airflow through the coil in the air handler, just take a $5 fin comb and scrape all the crud off the coil fins. This can make a dramatic difference. Hope this helps! ;)

SOURCE: I have a Ruud air-conditioner/heat pump and it blows 5 amp fuse.

It sounds like the thermostat wire going to the condenser is ground, It either got pulled loose and is touching the housing or as in most cases the wire got cut or was chewed by an animal. You need to turn electric off to both devices and physically inspect the thermostat wire going from the air handler to the outside unit, also inspect where they connect inside the unit. When you find the break, cut and strip each individual wire and securely wire nut each conducter red to red white to white and so on. There you go all fixed. That's when I give you the bill for $75...except this time you write that check to yourself. Good Luck

SOURCE: RUUD UBHA-14 J11SFJA air handler. The fan (blower) doesn?t runs

Absolutely, however, you want to properly diagnose the reason why the fan is not running. It could be a less expensive part than the fan motor itself.
First, check to see if you have the proper voltage going to the motor. I believe your motor requires 240volts ac. If you do not have 240 volts, you have a control problem.......either the thermostat is failing to close R & G or your blower relay may have failed to close the contacts necessary for your fan to operate.
If you have the voltage, then you want try spinning the blower wheel with your hand. Does it spin freely? Is the motor warm/hot? If so, turn everything off for an hour or so. As soon as your energize it, try spinning the motor with your hand again.....if it spins freely with no resistance and then starts running by itself, the problem is the run capacitor (approx $20.00 depending on where you purchase it from). If there is resistance when you try to spin it, the problem is most likely with the bearings and you will need to replace the motor.......if you have to replace the motor, go ahead and replace the capacitor also, making sure it is properly "matched" with your new motor.

I hope you find this to be very helpful to you, moving forward. :-)

SOURCE: RUUD uaka-036jaz not cooling, outside fan does not

Check your disconnect or breaker that is located close to the outside unit. Next you need to check the contactor in the outside unit. Set the thermostat to make the air come on then check the contactor. It should be pulled in closing the contacts. If it isn't the problem could be the contactor or thermostat. Next check the voltage on the load side with it pulled in. If that's good then check the capacitor. If it looks swollen, it's bad. You can also use a multimeter with the capacitor check function to do this. Let me know what you find.