Why would someone buy a heating (gas fuel) and cooling package unit?
wlarsen
| Posted in Mechanicals on
Hi!
I recently moved to CA and have started seeing a lot of homeowners installing heating and cooling package units, usually installed on the roof. These systems are gas-fueled, with a max AFUE of 81 or so. Why would someone buy one of these units instead of a full Air Source Heat Pump to do heating and cooling?
For example: http://www.lennox.com/products/packaged-units/LRP14GE/
Thanks for your help!
Whitney
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Replies
Installed price is one reason, capacity at low outdoor temps is another, very high electricity prices relative to local gas prices is another. But I agree, it makes no sense in most CA locations. The crummy gas-burner would typically be ridiculously oversized for the actual heat loads, and less comfortable than even a 1-speed heat pump that was right-sized.
I was under the impression that a Manual-J load calculation and oversizing factor of no more than 15% was required under CA Title 24, which must lead to some truly marvelously fudged numbers to make an oversized package unit fill the requirements. They are very popular in the southeastern US, where state codes don't (yet) have anything remotely like the stringent requirements for HVAC sizing & system commissioning found in California.
Thanks, thats extremely helpful!