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Which heat pumps are the BEopt models based on?

asked 2018-04-17 21:02:45 -0500

bwilbur gravatar image

Does anyone know which heat pumps (manufacturer & model) the BEopt default models are based on? I'm looking for the air source heat pump: SEER 22, and Mini-split heat pumps: E) & F)(ducted). The mini-split models are apparently derived from the NEEP ccASHP database [http://www.neep.org/initiatives/high-...] and I'm trying to figure out how the BEopt inputs were derived so I can do the same for other models.

(I apologize because I've asked this question before in the BEopt forum, but the forum has just been migrated to Unmet hours and apparently all previous threads have disappeared forever)

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answered 2018-04-18 10:46:22 -0500

updated 2018-04-18 10:47:11 -0500

Here is the information about mini-splits from @Eric Wilson:

I don't have the exact calculation procedure, but BEopt's variable tooltips provide some hints about which columns to use from the NEEP spreadsheet:

Minimum Heating Capacity [frac]: Minimum heating capacity as a fraction of nominal heating capacity at rated conditions. Can be derived from NEEP's Cold Climate Air-Source Heat Pump Specification Listing spreadsheet.

Maximum Heating Capacity [frac]: Maximum heating capacity as a fraction of nominal heating capacity at rated conditions. Can be derived from NEEP's Cold Climate Air-Source Heat Pump Specification Listing spreadsheet.

Heating Capacity Retention Fraction [frac]: The maximum heating capacity at X degrees F divided by the maximum heating capacity at 47 degrees F. The value for X is input in the "Heating Capacity Retention Temperature [F]" field. Can be derived from NEEP's Cold Climate Air-Source Heat Pump Specification Listing spreadsheet. BEopt uses a linear relationship between this point and the rating point to determine maximum heating capacity as a function of outdoor temperature.

Heating Capacity Retention Temperature [F]: The outdoor drybulb temperature at which the heating capacity retention fraction is defined.

Pan Heater [W/unit]: MSHPs designed for use in cold climates often include a pan heater in the outdoor unit as an optional or integrated accessory, to prevent ice build up from damaging the coil. This field specifies the power of the pan heater included in each outdoor unit. Pan heaters are assumed to operate when the compressor is running and the outdoor drybulb is less than 32 degrees F. Note that the pan heater typically reduces the Rated HSPF by 0.1-1.0 points; units with integrated pan heaters should use the Rated HSPF input of an equivalent unit without a pan heater. This input is available in NEEP's Cold Climate Air-Source Heat Pump Specification Listing spreadsheet. It is assumed that a new outdoor unit is needed every 1.5 tons (nominal cooling capacity).

In case it helps:

  • the "C" options are roughly equivalent to the Mitsubishi FE series
  • the "D" options are roughly equivalent to the Mitsubishi FH series
  • the "E" options are roughly equivalent to the Fujitsu AOU*RLS3H series

Information on air-source heat pumps can be found here: Improved Modeling of Residential Air Conditioners and Heat Pumps for Energy Calculations

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Asked: 2018-04-17 21:02:45 -0500

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Last updated: Apr 18