Rooftop Carrier AC blowing warm air

Thank you all for your quick responses. I will take all of your suggestions into consideration and will check them one-by-one until I find the cause of the issue.

Ralph

I have a few spare parts for a Carrier Air-V, none that I think can help you.

If you have lost ALL our coolant the unit will false out with an "AC PROBLEM" code (five flashes of the Green LED)... One problem on the Air V

Just off the compressor two lines drop down like a plumbing "P" or J trap (This is a vibration trap near as I can tell, actually a good idea)

The problem comes when the two lines actually TOUCH, as they "Trap" the vibrations of teh compressor they rub together and after long enough they get religion (Become holey) and woosh goes all your coolant.. IF this is the problem repalcement may be in order.

Carrier no longer makes 'em.

Advent Air makes both a 13.5KBTU and a 15KBTU (K means 1000) that fit the carrier base and rooftop. use carrier controls and actually work well.

And there is at least one other that fits as well.. Name begains with C,(IF I'm not mistaken) big name in RV A/C and dang if I can recall it just now.

Also, my new ADVENT AIR 15,000 BTU draws the same 13.5 Amps that my old Carrier 13,500 BTU unit drew.


Other possible issues: .... .When was the last time you cleaned the condenser coils up on the roof (you need to remove the outer shroude and a metal cover near the rear of the AC to do this)

If it's plugged up and they do plug up, no cooling will happen.

NOTE: this is the first thing to check cause the cost of repair is $0.00 if you fix it yourself, no parts needed.

Do you have a Wall Thermostat, or is your A/C controlled by knobs right on the unit itself? Wall thermostat usually goes with a Ducted system (several outlets in ceiling) and onboard knobs usually go with a non-ducted system (cold air outlets on the unit itself only).
How comfortable are you with..
...1. Getting/Being on a Roof? and...
...2. Involving minor Electrical Work?
Do you have/can you use...
...1. Clamp-On AC Ammeter?
...2. Digital Volt Ohm Meter (DVOM)?
...3. Perhaps a DVOM that measures Capacitance (MicroFarads/uF/MFD scale)?
What kind of power source were you plugged into when the A/C failed to deliver cold air? What can you plug into now? If you're using long or small gauge extension cords and adapters, you can't expect good performance from a rooftop A/C.

Don't put too much in to repair- most parts are not available, and those that are are expensive.

Old-Biscuit wrote:
Does the compressor come on?

Fan running in auto?

Bad compressor, bad start capacitor.

thats what I was thinking. If the compressor doesn't kick in theres a good chance of it being a capacitor.

Does the compressor come on?

Fan running in auto?

Bad compressor, bad start capacitor.

Take it to a HVAC repair company (not RV shop) and they will sometimes install ports and recharge it.
You have a good unit there and it would be a shame to replace it.

Sounds like it is out of coolant. Bad news is, most of them are "sealed" systems and do not have a provision for refilling, only replacing. Even if the coolant can be replaced by modification of the unit, there is still a leak somewhere. Long term advice, replace the unit.