Radio Shack 63-1090 indoor/outdoor temperature unit. Won't give outdoor readings. Temps are cold, -5F but it always worked before. Put in new batteries in the inside and outside units, wiped outdoor sensor clean, reset both units, no outdoor readings show up on indoor unit. Just started acting up 4-5 days ago during this latest cold spell (when we want the outside temperatures the most!). Does outside sensor need to be replaced or the whole unit, or do I have to be patient and wait for it to warm. Still, it registered and listed below zero readings in the past.

SOURCE: York Mini-Split Not Cooling? : (

This can only be a gas problem.
the split units goes on on and off if a shortage of gas is involved, the chances that you would here it wont be that big for the fans would make too much noise.
get a repair man for a re gas and all is well.

Good luck.

Wouter.

SOURCE: outdoor unit will not run

Some air conditioners have a thermostat that will not allow the compressor to run below a certain out side tempature as it will cause liquit to come back into the compressor(called slugging) and damage or destroy it.  

http://www.hitachi.com.au/productsearch.aspx?pId=62&

Felizardo Erilla

• 241 Answers
• Posted on Jan 26, 2009

SOURCE: blinking indicate at indoor unit

reset your unit by disconnecting the power supply for 10sec. and "on " the unit for testing. if error persist you need to replace your thermistor.

SOURCE: AC not cooling during the day

Your AC cooling efficiency is low when he ambient temperature is high and naturally it cools well when the outside temperature drops.

Please remove the filter on the grill and try to clean it under the tap water and after removing all the dust fix it back to the unit. This would increase the cooling efficiency of the unit.

Your AC is also five years old. Please avoid frequent opening of doors or windows.

Ensure that the exhaust fan and the blower of your unit are functioning normal.

The technician might not have done a proper job in fixing the area where the refrigerant would have leaked out. Please check the refrigerant pressure to ensure that no further refrigerant leak has taken place. Or even servicing your unit he would have punchered the tubes resulting in very slow leak of refrigerant resulting in no cooling or less cooling. It takes around a month to feel the pinch of it and the refrigerant. One fine morning after sometime the unit will run and it would start throwing hot air instead of cool breeze!

SOURCE: One of the indoor units blows air which is not

Sounds like the metering device in the one that's not working is clogged and not letting the refrigerant flow through the coil.