New A/C unit icing up
#1
10-01-21, 12:38 PM
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New A/C unit icing up
I've lived in my house for 6 years; in the past 6 months, both the compressor/air handler unit (in the attic) and the condenser (on a concrete pad outside) have been replaced. The copper tubing and inlet valve on the new condenser will ice up pretty heavily, but only if the return air filters are in place. If I take the return air filters out, there's some condensation (but I live in McAllen TX, in a very humid climate). As I said, I've lived in my house for 6 years, but this is a new problem. I've always previously been able to have the return air filters in place. Any ideas on what the underlying issue could be?
#2
10-01-21, 12:58 PM
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#3
10-01-21, 01:22 PM
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Freon has leaked out.
Refrigerant lines can kink, fans can stop moving, filters can become clogged, and things can leak. Any of these things causes a drop in pressure, allowing the refrigerant to expand too much and become too cold. ... A too-low level of refrigerant is also known to cause freezing up.
Refrigerant lines can kink, fans can stop moving, filters can become clogged, and things can leak. Any of these things causes a drop in pressure, allowing the refrigerant to expand too much and become too cold. ... A too-low level of refrigerant is also known to cause freezing up.
#5
10-01-21, 11:50 PM
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Welcome to the forums.
Wouldn't be a condensate drain issue.
Typically low on refrigerant would cause the evaporator to ice over.
Sounds like the system is very responsive to air flow. That's determined by filter/type, something put in front of the returns or registers closed down.
As roughneck mentioned.... what filters are you using ?
Wouldn't be a condensate drain issue.
Typically low on refrigerant would cause the evaporator to ice over.
Sounds like the system is very responsive to air flow. That's determined by filter/type, something put in front of the returns or registers closed down.
As roughneck mentioned.... what filters are you using ?
#6
10-02-21, 06:43 AM
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The new unit was installed three days ago, so I can rule out low refrigerant. I threw out the old return air filters and replaced them with the cheapest, thinnest ones I could find. Problem solved - no more ice.
#7
10-02-21, 07:58 AM
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Just because the system was recently installed, I don't think you can assume that the correct amount of refrigerant was added. Years ago my son had central air (split system) installed. It wasn't cooling well at all. I told him to call the contractor and come back to determine why. It turns out they hadn't added the correct amount of refrigerant. After putting more in, the air coming out of the ducts was ice cold.
