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Defrost Cycle

See Heat Pump. Also called "defrosting" and "going into a defrost."

When it gets below about 45 degrees, a heat pump running in HEAT mode may develop ice or frost on the coils. There are exceptions to the rule, however, as I have seen heat pumps defrost when it is abve 45 degrees and even in the 50s! If it gets frozen enough, it may have to defrost. A defrost cycle is initiated by the the reversing valve switching the flow of Freon and putting the unit in COOL mode. However, unlike when the unit is running in COOL mode on a hot day, the fan blades in outdoor unit are not spinning, and the system typically has its electric, gas, or oil backup heat running to prevent the heat pump from effectively air-conditioning the house while it is defrosting. Sometimes, depending on a number of factors, a steam or fog may appear above the heat pump (see Steam Show). A defrost cycle can last anywhere from less than a minute to ten minutes or more depending on a number of factors, including outdoor temperature, ice/frost buildup on the outdoor coils, whether or not it is raining or snowing, and what temperature the thermostat is set at.
The first time I saw a defrost cycle at my new house, I thought my heat pump wa broken and about to explode!

My heat pump is located right outside the master bedroom window, and it woke me up this morning when it went into defrost.

I was playing with my dog in the backyard on a chilly winter day, when my heat pump went into defrost and scared her so much that she started barking at it.
Defrost Cycle by AutoHVACNut March 15, 2012
Related Words
Bored backwards, emphasizes the idea of being bored. Intense boredom, bored beyond limits, extremely bored. Mostly used on forums, and in chat rooms, or in video games, commonly referred to as part of "1337speak"
Kyle was super derob today, when his computer was broken.

I am so derob, there is nothing to do.

Aaron is derob because he has to use a 333mhz laptop.
derob by squizzi December 14, 2008

defrocked 

What happens to a priest when he is accused and found guilty of touching young children.
Father Julian was defrocked after I accused him of fondling my genitals. He had abused me for 8 years, I didn't know any better. Shame on you Father Julian.
defrocked by J-Ru September 15, 2003
When you revisit people who used to like you and decide to give them a chance to date you.
Becky: "Wow, Is Jocelyn dating Andrew? I thought they were just friends."
Karen: "Because of Covid, Jocelyn decided to defrost Andrew"
Defrost by ibeyuranh January 13, 2022
a setting on most cars and vehicles which removes frogs from the windshield
the window is all froggy better turn on the defrog
defrog by Matt Huff November 11, 2009

defrontalized

When substance abuse, poor nutrition or aging has taken its toll on the frontal lobe, leaving a person with impaired judgment.
His behavior was indicative of a fully defrontalized individual and the damage made it pronounced and embarrassing.
defrontalized by Dr Bunnygirl December 24, 2018