Heat pump for Boston home
ketzelkat
| Posted in GBA Pro Help on
Do you know of a cold-climate or all-climate heat pump for the 1400 sq. ft. second floor (4 bedrooms) of my all-electric Boston home (to replace my old Carrier heat pump, located in the attic)?
I am looking for a unit that will operate with an outside air temperature in the teens. If no system is available, what conventional system would you prefer (eg, Carrier, Trane , Lennox)?
Thank you,
Bob
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Replies
Robert,
Your first step is to perform a heat-loss calculation.
Among your options:
1. Mitsubishi Mr. Slim Hyper-heat, model number PUZHA36NHA. This unit is rated for performance down to an outdoor temperature of -13 degrees F. Heating capacity is 18,000 Btuh at -13 F. According to the manufacturer, "These models exhibit 100% of rated heating capacity at 5°F and 87% at -4°F outdoor ambient." For more information, see Mr. Slim P-Series.
2. The Lennox XP14 is an air-source heat pump rated for performance at outdoor temperatures down to -15 degrees F. Its heating capacity is 11,000 Btuh at 5 degrees F and 5,800 Btuh at -15 degrees F.
Thank you so much Mr. Holladay. Can the Mr Slim system be connected to my existing attic ductwork? Do you know of an experienced installer in the Boston area?
Thank you,
Bob
Robert,
Q. "Can the Mr Slim system be connected to my existing attic ductwork?"
A. No.
Q. "Do you know of an experienced installer in the Boston area?"
A. Sorry -- no, I don't.
Thank You
Bob
Mr Holladay,
A final question, if I may: Is the Carrier Greenspeed inverter a satisfactory solution for the Boston winter? Carrier claims it works down to 5 degrees air temperature, and is very efficient.
Thank you again,
Bob
Robert,
"Greenspeed Intelligence" is a marketing phrase developed by Carrier to describe a type of control system used on some of Carrier's air-source heat pumps. Unfortunately, Carrier's marketing materials are rather vague on details. From what I can gather, "Greenspeed Intelligence" refers to a package of features that allow these heat pumps to modulate their output.
I'm not familiar enough with Carrier's products to have an opinion on their heat pumps. You might want to ask your supplier about the equipment's COP at 5 degrees F.