Cold Climate Heat Pump Capacity
Gree FLEXX (ducted, R-32): Heating Capacity at 5F and Below
The MAX heating capacity the Gree FLEXX (ducted, R-32) holds as it gets cold, from the AHRI-certified NEEP record (AHRI 215213329), with the maintained-% and a balance-point readout.
MAX Capacity by Temperature
| Outdoor temperature | Type | Heating capacity |
|---|---|---|
| 47F | RATED | 25,000 BTU/hr |
| 47F | MAX | 25,400 BTU/hr |
| 17F | MAX | 21,600 BTU/hr |
| 5F | MAX | 25,000 BTU/hr |
| -22F (cold floor) | MAX | 18,000 BTU/hr |
The “will it heat my house at 5F” answer is the MAX at 5F (25,000 BTU/hr), shown next to the rated 47F capacity so you see both. Capacity below -22F is not published for this line, so it is not extrapolated here.
Maintained Capacity at 5F
At 5F the Gree FLEXX (ducted, R-32) holds 25,000 BTU/hr. That is 100% of its rated 47F capacity (25,000 / 25,000), and 98.4% of its MAX 47F capacity (25,000 / 25,400). Both are true; the denominator is always stated. NEEP floors its stored percentage to a whole number (100% and 98% respectively); the computed ratio is shown above.
Balance Point & Backup Heat
The balance point is where this model's declining capacity curve crosses the load line, which runs from zero at 65F to your full design load at the design temperature. Enter your own design heat load in the calculator below for your numbers. This is a readout, not a substitute for a Manual-J load calculation.
Run It for Your Temperature and Load
Source
Capacity and COP transcribed from the AHRI-certified NEEP cold-climate air-source heat pump database, pinned to AHRI certificate 215213329 for outdoor unit FXU24HP230V1R32AO: NEEP ccASHP record, accessed 2026-07-11. The manufacturer engineering data or a Manual-J by an HVAC pro has the final say.
An R-32 ducted unit rated to the coldest floor in this roster, -22F (18,000 BTU/hr). It delivers its full rated 25,000 at 5F, and its capacity curve is non-monotonic at MAX, dipping at 17F and recovering at 5F, which is real and printed by NEEP.
Frequently Asked Questions
What is the Gree FLEXX (ducted, R-32) heating capacity at 5F?
The Gree FLEXX (ducted, R-32) puts out 25,000 BTU/hr MAX at 5F, which is 100% of its 25,000 BTU/hr rated capacity at 47F (and 98.4% of its 25,400 MAX at 47F). This is the number that answers whether it can heat your house on a cold day. Pinned to AHRI certificate 215213329.
How low can the Gree FLEXX (ducted, R-32) operate?
The lowest rated row on the AHRI-certified NEEP record is -22F, where it still delivers 18,000 BTU/hr MAX. Below that temperature the capacity is held at the -22F row rather than extrapolated to an unpublished colder number.
What is the Gree FLEXX (ducted, R-32) COP at 5F?
The COP at MAX capacity at 5F is 2. That is the coefficient of performance at the maximum output the unit reaches at 5F. Only the MAX-capacity COP is published here; the minimum-output COP at extreme lows is artifactual and is not a useful cold-weather figure.
What is the balance point for the Gree FLEXX (ducted, R-32)?
It depends on your home's heat loss. Against a 45,000 BTU/hr design load at 5F, the Gree FLEXX (ducted, R-32) balances at 33.4F and needs 20,000 BTU/hr (5.86 kW) of backup heat at the 5F design temperature. Enter your own load in the calculator for your balance point. A Manual-J load calculation has the final say.
Other Cold-Climate Heat Pumps
Mitsubishi P-Series Hyper-Heat (ducted)
38,000 BTU/hr at 5F (95% of rated).
Bosch IDS (ducted)
21,800 BTU/hr at 5F (63.7% of rated).
Fujitsu AIRSTAGE XLTH (wall ductless)
23,200 BTU/hr at 5F (96.7% of rated).
Carrier Performance (ducted)
26,200 BTU/hr at 5F (82.4% of rated).
Daikin Aurora (wall ductless)
21,600 BTU/hr at 5F (100% of rated).
LG Ceiling / ducted (R-32)
36,000 BTU/hr at 5F (90% of rated).
MRCOOL Universal (ducted DIY)
22,000 BTU/hr at 5F (91.7% of rated).
Capacity at 5F Chart (All Models)
Every line on one table: rated 47F, MAX at 17F and 5F, the cold floor, and COP.
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