My ruud blinks three times - Ruud UAKA037 Air Conditioner

Pull the hose out from pressure switch and check for any restriction ,also clean where hose is connected to from furnace because that will get clogged

62-24084-02 LED CODES
POWER LED - GREEN
ON - Normal
OFF - No power to board
OK LED - GREEN
One Blink - One hour retry delay
Two Blinks - Pressure switch failure (remains open)
Three Blinks - Limit switch fault
Four Blinks - Pressure switch failure (remains closed)
Five Blinks - Twinning fault
FLAME LED - YELLOW
ON - Good flame
Rapid Blink - Flame present with gas valve de-energizing
Slow Blink - Marginal flame

on the board itself or on the schematic there is a legend that will tell you what the blinks mean. start there. its just a diagram that gives you the fault according to the number of blinks

There is a limit switch that is likely opening. Be sure your filters are clean and all registers and grilles are open and not obstructed. If the problem continues, you may have a dirty indoor coil or undersized duct work. Some models have a window where you can observe the LED lights. If when the furnace shuts down you see any blinking, you need to count the flashes and we can figure out what the problem is from there.

4 Blinks is an error code of a sticking pressure switch. A pressure switch is a safety, which in this case is being used to verify that your furnace is drafting properly. Yours in particular is sticking in the closed position even after the call for heat is satisfied. The control board checks to make sure the switch is open the next time there is a call for heat, and when it sees that the pressure switch is already closed even before the draft inducer motor comes on, it knows there is a problem....hence the error code. If you tap on the pressure switch, it may cause the contacts to open. Usually you will see a rubber hose attached to the pressure switch and 2 or three wires depending on what type of switch it is. You will probably have to replace the switch, but maybe this will get you thru the night. Hope this helps!

sounds like you have a heat pump heat pumps dont work below 30* temps you should have some type of backup heat

Check the data information on the unit there should be a troubleshooting guide that tells you what the two lights blinking once means. hope this helps.good luck. normally found with schematic

the fuse that your refering to is on the control board indie of the furnace. shjould be a 3 amp. good luck.

Te flame symbol on the T-stat is just telling you that the T-stat is calling for heat.

What you need to do is go to the furnace and see if there is a blinking light. If there is count the blinks and look for a blink code list on the wiring diagram.(Usually found on the main panel.)

After you have done that, disconnect power to the unit, and then reconnect after a few minutes. This will reset any auto switches if they are tripped.

Chances are the problem will occur again even if the furnace does fire back up, but it "may" get you through the night until you can either diagnose the problem or get a service tech in.

Ideally, have someone else turn the power back on, and the thermostat, while you are watching the furnace to see exactly what is happening.

If it does not operate properly at that time, let me know exactly what it is/is not doing and we can go from there.

4 blinks is "pressure switch closed" there are 2 in the system according to the wiring diagram one for the vent system  and one for the drain system ... I just wiggled them and heard one "click" the fault light quit blinking and when I pushed the safety switch back in the furnace fired right up.  That being said is there a good website for learning how to maintain your own furnace?  I'll call a pro if I have to, but shoot I can fix a jet engine... this shouldn't be much worse.
Thanks  dan