Rheem Heat Pump 40-Gallon (PROPH40 T0 RH120-M) is a heat pump (hybrid electric) water heater from Rheem with a 36 gallon rated tank and a 45 gallon first-hour rating at a 2.8 UEF — 780 kWh/yr certified use, 62.3 in tall.
Efficiency
Uniform Energy Factor (UEF)
2.8
Annual electricity use
780 kWh/yr
Recovery efficiency
387 %
General
Fuel
Electric
Capacity
First-hour rating
45 gal
Rated storage volume
36 gal
Draw pattern
Low
Heat pump
Heat pump type
120 Volt Integrated HPWH
Refrigerant (GWP)
R-134a (GWP:1430)
Compressor low-temp cutoff
210 °F
Installation
Input voltage
120
Max current draw
4.5 A
Smart features
Smart / connected capable
No
Dimensions
Height
62.3 in
Diameter
20.3 in
Certification
ENERGY STAR certified
Yes
Who is the Rheem Heat Pump 40-Gallon (PROPH40 T0 RH120-M) for?
Its 45 gallon first-hour rating suits a
household of 1–2 people under DOE sizing guidance.
Estimated running cost: about $133/year at the national
average electricity rate (780 kWh/yr certified use).
Runs on a 120 V circuit (up to 4.5 A) — often no new wiring needed.
The heat pump compressor operates down to 210 °F ambient — below that, backup
elements take over.
Also sold as
The Rheem Heat Pump 40-Gallon (PROPH40 T0 RH120-M) is certified hardware that Rheem and its partner brands
publish under 8 names. The same specifications apply to every
variant:
Is the Rheem Heat Pump 40-Gallon (PROPH40 T0 RH120-M) ENERGY STAR certified?
Yes, the Rheem Heat Pump 40-Gallon (PROPH40 T0 RH120-M) holds a current ENERGY STAR certification for water heating efficiency (UEF 2.8).
How much does the Rheem Heat Pump 40-Gallon (PROPH40 T0 RH120-M) cost to run per year?
About $133 per year at national average energy rates, based on its certified annual energy use under the DOE test draw pattern. Your rate and usage change this figure.
What electrical circuit does the Rheem Heat Pump 40-Gallon (PROPH40 T0 RH120-M) need?
The Rheem Heat Pump 40-Gallon (PROPH40 T0 RH120-M) runs on a 120 V circuit drawing up to 4.5 A — many installations use an existing outlet with no new wiring.
Is the Rheem Heat Pump 40-Gallon (PROPH40 T0 RH120-M) a smart water heater?
No, the Rheem Heat Pump 40-Gallon (PROPH40 T0 RH120-M) is not connected-capable — it has no app connectivity or demand-response support.
