Anyone have a clue why my A/C will not cool?

[JDgreen227]

Nine year old Lennox furnace and A/C unit, and no matter how much we turn down the thermostat the air coming from the registers never gets below 76 degrees. Filter on the furnace is almost new, condensate drain from the coil is clear, compressor seems to run fine but the temperature never really gets cooler than that 76 degrees. It's 88 degrees outside as I type this and the house seems to be really humid despite the A/C running full time. I checked and the humidity indoors is 73% while outside it is 47%. Did a search online and most of the information I found said if the A/C doesn't seem to cool and the indoor humidity level seems high, the drain from the coil is likely plugged. Not here, as I know for a fact the drain line is clear because I can see the condensation pouring out and I also disconnected it from the primary outlet at the bottom of the coil to be sure it was flowing easily. Oh, yes...thermostat has new batteries and it runs on 115 volts anyway. I cannot figure this one out.

Any ideas? Thanks for the input.

 

[rekees4300]

Re: Anyone have a clue my my A/C will not cool?

Maybe the compressor needs to be recharged? Suggest calling a HVAC service guy.

 

[murphy1244]

Re: Anyone have a clue my my A/C will not cool?

on the condensor there will be two lines going in one 3/4 and one 3/8. the big one should feel cold and have sweat on it. how long does the unit take to cycle?

 

[Bob77064]

Re: Anyone have a clue my my A/C will not cool?

How hot was it outside? The A/C is designed for a certain temperature range and most places have been much hotter lately.

 

[JDgreen227]

Re: Anyone have a clue my my A/C will not cool?

Maybe the compressor needs to be recharged? Suggest calling a HVAC service guy.

I was wondering if somebody had a clue as to what it might be before I called for service. Was thinking my unit may need to be recharged but the other one we have (AC) is a 1993 vintage Lennox and has never needed recharging. Probably because that one uses Freon and the newer one uses R410A.

Thanks !!

 

[TCJatko]

Re: Anyone have a clue my my A/C will not cool?

Maybe cleaning the evaporator will help (dust buildup).

 

[JDgreen227]

Re: Anyone have a clue my my A/C will not cool?

on the condensor there will be two lines going in one 3/4 and one 3/8. the big one should feel cold and have sweat on it. how long does the unit take to cycle?

Large line is barely cool and not sweating. Thanks for the information !!!

 

[murphy1244]

Re: Anyone have a clue my my A/C will not cool?

You have a leak that needs to be found and a recharge
Do what Depmandog said and see if things get colder.You should be able to do a 20% drop from outside temp..

 

[Depmandog]

How long has it been since you have cleaned the outside unit?

It's easy to do, and if the coil fins are plugged with dirt and debris you will get little or no cooling.

Turn the AC off, remove the top which will have the fan and motor attached, set it aside. (
It will have a electrical connector to unhook the two wires from the motor). Slip the top cover off. Take a garden hose and spray from the inside out - forcing the dirt out. Take your time and do a thorough job. After I clean it going left to right side to side, I start over and work am up down pattern.

Replace the covers and fire it up. If your Freon is ok - this should fix your problem.

I did mine about three weeks ago - and it made a major difference. Taking the unit apart consists of a dozen screws max. Real easy!!

 

[Bob77064]

Re: Anyone have a clue my my A/C will not cool?

How long has it been since you have cleaned the outside unit?

It's easy to do, and if the coil fins are plugged with dirt and debris you will get little or no cooling.

Turn the AC off, remove the top which will have the fan and motor attached, set it aside. (
It will have a electrical connector to unhook the two wires from the motor). Slip the top cover off. Take a garden hose and spray from the inside out - forcing the dirt out. Take your time and do a thorough job. After I clean it going left to right side to side, I start over and work am up down pattern.

Replace the covers and fire it up. If your Freon is ok - this should fix your problem.

I did mine about three weeks ago - and it made a major difference. Taking the unit apart consists of a dozen screws max. Real easy!!

Good idea, I probably need to do mine.