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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 8768
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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Installed 2010 a Rheem 3 ton whole house air cond. system.

Customer Question

installed 2010 a Rheem 3 ton whole house air cond. system.
new ductwork 2 yrs old, and dual U/V lites one yr old.
and new liquid line set 10 months old.
last test on condenser read 22.10 amps
before in May 13.01 and in Dec 2014 was 8.1
I am now being told we should install an in line dehumidifier
to protect coils ,,, but in the house humidity reads 38% dry.
What do you think???
Submitted: 2 years ago.
Category: HVAC
Expert:  Phil replied 2 years ago.


Compressor amperage increases as the outside air temperature increases.. it is not a good metric by itself. of the largest copper tube that attaches to the outside unit runs cool or sweating then the system is largely OK.

Those remarks about an inline dehumidifier to protect the coils is hogwash... makes no sense at all. it sounds so far like the company you are working with is good at selling a lot of extra's, needed or not.

38% is in the ideal humidity range, a well functioning AC system provides dehumidification by itself, the only thing need to protect the coils is regular air filter changes.


Please remember to rate my service before you leave today. It is how I earn a living, and does not increase your charges.

If you need anything else, just let me know. You can continue asking follow-up questions at no additional cost.

Customer: replied 2 years ago.
Thank you
Largely what I suspected but wanted a second opinion.
Expert:  Phil replied 2 years ago.

You are welcome Shaun,

Please rate my service, lacking that I loose money, the company only pays me part of your deposit if you rate positively. That does not affect your charges, but is how I earn a living.