Cala Systems, Inc RDH6524M1 65-Gallon is a heat pump (hybrid electric) water heater from Cala Systems, Inc with a 65 gallon rated tank and a 79 gallon first-hour rating at a 3.61 UEF.
Our take
Cala's certification is unusually sparse: a 3.61 UEF (a whisker under the 3.64 class median), a 79-gallon first-hour rating on the median, R-513A refrigerant, and a 30 A maximum draw implying a 40 A breaker — the heaviest circuit requirement in the class — but no published annual-energy figure, dimensions, or compressor cutoff in the ENERGY STAR record. That makes running-cost and siting comparisons against fully documented rivals impossible from certified data alone. The capacity and efficiency that are published read as squarely mid-class. Single badge, no connectivity listed.
Trade-off: Missing certified data (cost, dimensions, cutoff) plus the class's heaviest circuit.
Efficiency
Uniform Energy Factor (UEF)
3.61
Recovery efficiency
4.2 %
General
Fuel
Electric
Capacity
First-hour rating
79 gal
Rated storage volume
65 gal
Draw pattern
High
Heat pump
Heat pump type
240 Volt Integrated HPWH
Refrigerant (GWP)
R-513A (GWP:630)
Installation
Input voltage
240
Max current draw
30 A
Smart features
Smart / connected capable
No
Certification
ENERGY STAR certified
Yes
Who is the Cala Systems, Inc RDH6524M1 65-Gallon for?
Its 79 gallon first-hour rating suits a
household of 5+ people under DOE sizing guidance.
Needs a 240 V circuit; at 30 A max draw plan for a 40 A breaker (NEC 125% continuous-load rule).
Is the Cala Systems, Inc RDH6524M1 65-Gallon ENERGY STAR certified?
Yes, the Cala Systems, Inc RDH6524M1 65-Gallon holds a current ENERGY STAR certification for water heating efficiency (UEF 3.61).
What electrical circuit does the Cala Systems, Inc RDH6524M1 65-Gallon need?
The Cala Systems, Inc RDH6524M1 65-Gallon runs on a 240 V circuit drawing up to 30 A; per the NEC 125% continuous-load rule plan for at least a 40 A breaker (check the installation manual for the required circuit).
Is the Cala Systems, Inc RDH6524M1 65-Gallon a smart water heater?
No, the Cala Systems, Inc RDH6524M1 65-Gallon is not connected-capable — it has no app connectivity or demand-response support.
