Heating, Air Conditioning, Fridge, HVAC/AC condensate


Hi Joe,

If I understand correctly, avg AC condensate is 0.3 - 0.5 gal/hr/ton.  I'm on the low side at 0.3 and I'd like to know if and how I can get more toward the 0.5.

I have a 3-bedroom rambler on a slab stick-built in 1953. The 1997 Carrier AC/furnace unit is in the middle of the house and the air vents run under the slab.  The compressor is on the side of the house with a 45 foot run for the 3/8 HP and 3/4 LP tubing.  The compressor is 2.5 ton and the evap coil is 3.0 ton.

Ever since the AC was installed it has cooled very well set on 72 deg F, but the inside RH is almost always around 60 in the summer.

Yesterday and today I tried changing the blower speed but only with modest results.  Outside temp was 94 deg F with RH about 50.  Thermostat was set to 72 deg F but it didn't get much below 75 and inside RH hovered around 62 percent. The low and med hi speeds both resulted in about 0.3 gal/hr/ton and hi speed about 0.27 gal/hr/ton.  On all speeds the pre coil dry temp was about 75 deg F and the post coil temp was about 55 on low speed, 57.5 on med hi speed, and 58.5 on hi speed as read about 6 - 8 inches from the coil.  The air filter was clean and everything seemed to be functioning normally -- except for the low condensate.

I've read that units after the early 90's are more energy efficient and, by default, are less condensate-efficient, but, gee wiz, I'd like to think I could get more than 0.3.

I also thought of low Freon, but post coil temps seem to be in line and, besides, it's been no different since it was new.

Is there any hope other than a new unit?

Thank you so much for your help.  I really appreciate folks like you who take the time to help others!



Having a correctly sized tonnage  helps, your system may not be running long enough to remove the moisture. If your unit is indeed sized correctly , your refrigerant charge or your metering device may not be set correctly. Optimal performance is achieved if you have a matched indoor unit to outdoor unit, a correctly sized unit , a correctly charged system, a metering device that is set correctly, correctly sized and balanced ductwork. No surrounding air leaking into your return ducts. Google superheat and subcooling to see the importance of having the metering device and refrigerant charge correct.Also your indoor coil needs to be extremely clean for proper heat transfer and moisture removal.Also your outdoor unit coil needs to be clean.  

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40+ years diversified experience.An HVAC/Refrigeration Self Employed Contractor since 1986. NATE Certifield. Answer questions pertaining to Residential and Commercial Air Conditioning , Warm Air Heating, Heat Pump systems.Mechanical and Electrical troubleshooting of these systems.Be as detailed as possible when describing problem.Packaged unit or split systems.No appliance questions.


Installation and Troubleshooting, Mechanical and Electrical, in following areas, Refrigeration ( Walk In and Reach In Coolers and Freezers ) Commercial Roof Top and Packaged Heating/Cooling ( Natural Gas,Propane, Electric, and Heat Pumps ) Computer Room Air Conditoning Systems,Commercial Residential Packaged and Split Systems Air Conditoning and Heat Pumps.Warm Air Oil , Natural and Propane Gas Heating systems.

Graduated from Private Technical School in 1975. An HVAC/Refrigeration Contractor . Have Unlimited Heating/Piping and Cooling Contractor License.Limited Sheetmetal Contractors License.NATE Certifield. York Certifield Master Heat Pump Technician 1986. Served 33 years combination Active Duty Air Force , Air Force Reserves and Air National Guard in the HVAC/Refrigeration Shop/Mechanical Shop. Troubleshooting/Installing HVAC/Refrigeration Equiptment Worldwide. Retiring in 2003 as a Senior NCO ,and a Mechanical Superintendent.

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