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Source-backed model record
Cala Systems, Inc RDH6524M1
This page separates current ENERGY STAR certification fields from independently reviewed manufacturer fields. It is not a purchase recommendation or an installation approval.
Product details
Decision briefing from current source records
Use these source-backed facts to identify what can be compared and where current data is unavailable. They do not establish household fit, installation approval, operating cost, price, availability, or a preferred model.
Hot-water delivery and tank
Compare these listed values with a hot-water requirement you determined independently. No listed value establishes household fit by itself.
| Source layer and field | Current source-backed status |
|---|---|
| ENERGY STARENERGY STAR storage volume | 65 gal Verified valueSource: ENERGY STAR certified-product dataset Verified 2026-09-01; revalidation due before 2026-09-04. |
| ENERGY STARENERGY STAR first-hour rating | 79 gal Verified valueSource: ENERGY STAR certified-product dataset Verified 2026-09-01; revalidation due before 2026-09-04. |
| ManufacturerManufacturer nominal tank capacity | 65 gal Verified valueSource: Cala RDH6524M1 specifications, Page 1 > Tank capacity Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerManufacturer storage volume | Official sources conflictSource: Cala RDH6524M1 specifications, Page 1 > Tank capacity Verified 2026-08-26; revalidation due before 2026-09-25.ENERGY STAR certified HPWH record 4478534, record 4478534 > specifications.storage_volume_gallons Verified 2026-09-01; revalidation due before 2026-09-04. |
| ManufacturerManufacturer first-hour rating | Official sources conflictSource: Cala RDH6524M1 specifications, Page 1 > First Hour Rating Verified 2026-08-26; revalidation due before 2026-09-25.Cala RDH6524M1 EnergyGuide label, Page 1 > Capacity (first hour rating) Verified 2026-08-26; revalidation due before 2026-09-25.ENERGY STAR certified HPWH record 4478534, record 4478534 > specifications.first_hour_rating_gallons Verified 2026-09-01; revalidation due before 2026-09-04. |
| ManufacturerManufacturer recovery rate | Not found in reviewed sourcesSource: Cala RDH6524M1 specifications Verified 2026-08-26; revalidation due before 2026-09-25.Cala RDH6524M1 installation and operation manual Verified 2026-08-26; revalidation due before 2026-09-25. |
Physical fit and service access
Compare product dimensions with measured space. Product dimensions are not installation clearances; verify every clearance and service-access requirement separately.
| Source layer and field | Current source-backed status |
|---|---|
| ManufacturerProduct height | 67 in Verified valueSource: Cala RDH6524M1 specifications, Page 1 > Product dimensions Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerProduct width | Not found in reviewed sourcesSource: Cala RDH6524M1 specifications Verified 2026-08-26; revalidation due before 2026-09-25.Cala RDH6524M1 installation and operation manual Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerProduct depth | Not found in reviewed sourcesSource: Cala RDH6524M1 specifications Verified 2026-08-26; revalidation due before 2026-09-25.Cala RDH6524M1 installation and operation manual Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerProduct diameter | 24 in Verified valueSource: Cala RDH6524M1 specifications, Page 1 > Product dimensions Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerEmpty weight | Not found in reviewed sourcesSource: Cala RDH6524M1 specifications Verified 2026-08-26; revalidation due before 2026-09-25.Cala RDH6524M1 installation and operation manual Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerMinimum room volume | Not found in reviewed sourcesSource: Cala RDH6524M1 installation and operation manual Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerSide clearance | Not found in reviewed sourcesSource: Cala RDH6524M1 installation and operation manual Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerFront service clearance | Not found in reviewed sourcesSource: Cala RDH6524M1 installation and operation manual Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerTop clearance | 10 in Verified valueSource: Cala RDH6524M1 installation and operation manual, Page 14 > Height clearance Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerRear clearance | Not found in reviewed sourcesSource: Cala RDH6524M1 installation and operation manual Verified 2026-08-26; revalidation due before 2026-09-25. |
Electrical requirements
Compare only with circuit information confirmed for the installation. Verify the current instructions and required work with a qualified professional.
| Source layer and field | Current source-backed status |
|---|---|
| ENERGY STARENERGY STAR input voltage | 240 V Verified valueSource: ENERGY STAR certified-product dataset Verified 2026-09-01; revalidation due before 2026-09-04. |
| ManufacturerManufacturer input voltage | 240 V Verified valueSource: Cala RDH6524M1 specifications, Page 1 > Power Verified 2026-08-26; revalidation due before 2026-09-25.Cala RDH6524M1 installation and operation manual, Page 24 > Electrical Verified 2026-08-26; revalidation due before 2026-09-25.ENERGY STAR certified HPWH record 4478534, record 4478534 > specifications.input_voltage Verified 2026-09-01; revalidation due before 2026-09-04. |
| ManufacturerMinimum circuit ampacity | Not found in reviewed sourcesSource: Cala RDH6524M1 specifications Verified 2026-08-26; revalidation due before 2026-09-25.Cala RDH6524M1 installation and operation manual Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerMaximum overcurrent protection | Not found in reviewed sourcesSource: Cala RDH6524M1 specifications Verified 2026-08-26; revalidation due before 2026-09-25.Cala RDH6524M1 installation and operation manual Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerRecommended breaker size | 30 A Verified valueSource: Cala RDH6524M1 specifications, Page 1 > Circuit Verified 2026-08-26; revalidation due before 2026-09-25.Cala RDH6524M1 installation and operation manual, Page 24 > Circuit breaker Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerCircuit requirement | 240 V single-phase AC power with a 30 A double-pole breaker Verified valueSource: Cala RDH6524M1 installation and operation manual, Page 24 > Circuit requirement Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerConnection type | Hardwired through the unit junction box Verified valueSource: Cala RDH6524M1 installation and operation manual, Page 27 > Electrical connection Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerResistance element power | 4500 W Verified valueSource: Cala RDH6524M1 specifications, Page 1 > Resistance elements Verified 2026-08-26; revalidation due before 2026-09-25. |
Location, air, ducting, and condensate
Confirm each published location, airflow, temperature, ducting, and drain requirement. An unavailable value is an unresolved check, not permission.
| Source layer and field | Current source-backed status |
|---|---|
| ManufacturerAllowed location types | basement, garage, crawlspace, ventilated utility closet Verified valueSource: Cala RDH6524M1 installation and operation manual, Page 14 > Installation location Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerMinimum operating air temperature | 37 °F Verified valueSource: Cala RDH6524M1 specifications, Page 1 > Ambient operating range Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerMaximum operating air temperature | 120 °F Verified valueSource: Cala RDH6524M1 specifications, Page 1 > Ambient operating range Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerOperating temperature context | Surrounding-air operating range published for the exact RDH6524M1 Verified valueSource: Cala RDH6524M1 specifications, Page 1 > Ambient operating range Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerDucting supported | Yes — verifiedSource: Cala RDH6524M1 installation and operation manual, Page 29 > Ducting Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerInlet duct diameter | 8 in Verified valueSource: Cala RDH6524M1 installation and operation manual, Page 29 > Air inlet Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerOutlet duct diameter | 8 in Verified valueSource: Cala RDH6524M1 installation and operation manual, Page 29 > Air outlet Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerMaximum equivalent duct length | 40 ft Verified valueSource: Cala RDH6524M1 installation and operation manual, Page 31 > Maximum equivalent duct length Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerDuct configuration notes | No ducting is needed when any listed room/opening condition is met; otherwise the system may need ducting and the installer should determine the configuration. Verified valueSource: Cala RDH6524M1 installation and operation manual, Page 15 > Room and ducting rules Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerCondensate drain required | Yes — verifiedSource: Cala RDH6524M1 installation and operation manual, Page 16 > Condensate drain Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerDrain connection size | 0.75 in Verified valueSource: Cala RDH6524M1 specifications, Page 1 > Condensate connection Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerCondensate pump included | Not found in reviewed sourcesSource: Cala RDH6524M1 installation and operation manual Verified 2026-08-26; revalidation due before 2026-09-25.Cala RDH6524M1 specifications Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerDrain notes | Route condensate to a nearby drain; if no suitable drain is available, a condensate pump may be necessary. Verified valueSource: Cala RDH6524M1 installation and operation manual, Page 16 > Condensate routing Verified 2026-08-26; revalidation due before 2026-09-25. |
Efficiency and operating information
These are listed product metrics, not a prediction of household energy use, utility cost, or savings.
| Source layer and field | Current source-backed status |
|---|---|
| ENERGY STARENERGY STAR heat-pump type | 240 Volt Integrated HPWH Verified valueSource: ENERGY STAR certified-product dataset Verified 2026-09-01; revalidation due before 2026-09-04. |
| ENERGY STARENERGY STAR fuel | Electric Verified valueSource: ENERGY STAR certified-product dataset Verified 2026-09-01; revalidation due before 2026-09-04. |
| ENERGY STARENERGY STAR Uniform Energy Factor | 3.61 Verified valueSource: ENERGY STAR certified-product dataset Verified 2026-09-01; revalidation due before 2026-09-04. |
| ENERGY STARENERGY STAR listed annual electric usage | N/ASource: ENERGY STAR certified-product dataset Verified 2026-09-01; revalidation due before 2026-09-04. |
| ManufacturerManufacturer Uniform Energy Factor | Official sources conflictSource: Cala RDH6524M1 specifications, Page 1 > Uniform Energy Factor Verified 2026-08-26; revalidation due before 2026-09-25.Cala RDH6524M1 EnergyGuide label, Page 1 > Uniform Energy Factor Verified 2026-08-26; revalidation due before 2026-09-25.ENERGY STAR certified HPWH record 4478534, record 4478534 > specifications.uniform_energy_factor Verified 2026-09-01; revalidation due before 2026-09-04. |
| ManufacturerManufacturer listed annual electric usage | Verification blocked |
| ManufacturerHeat-pump capacity | Not found in reviewed sourcesSource: Cala RDH6524M1 specifications Verified 2026-08-26; revalidation due before 2026-09-25.Cala RDH6524M1 installation and operation manual Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerMaximum setpoint | Verification blocked |
| ManufacturerOperating modes | Boost Mode Verified valueSource: Cala RDH6524M1 installation and operation manual, Page 48 > Boost Mode Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerMode descriptions | Boost Mode: Temporarily increases hot-water capacity for expected heavier-than-normal usage; energy usage will be higher. Verified valueSource: Cala RDH6524M1 installation and operation manual, Page 48 > Boost Mode Verified 2026-08-26; revalidation due before 2026-09-25. |
Sound and documented features
These rows report only currently verified exact-model facts. A missing feature value does not mean the feature is absent.
| Source layer and field | Current source-backed status |
|---|---|
| ManufacturerRated sound level | Verification expired |
| ManufacturerSound test context | Internal Cala test based on NEEA v6.0 Appendix D at 55 Hz Verified valueSource: Cala RDH6524M1 specifications, Page 1 > Sound test note Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerConnectivity supported | Yes — verifiedSource: Cala RDH6524M1 specifications, Page 1 > Connectivity Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerLeak detection supported | Yes — verifiedSource: Cala RDH6524M1 specifications, Page 1 > Leak detection Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerDemand response capable | Yes — verifiedSource: Cala RDH6524M1 installation and operation manual, Page 47 > Demand response Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerIntegrated mixing valve | Yes — verifiedSource: Cala RDH6524M1 specifications, Page 1 > Mixing valve Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerBackup resistance elements | Yes — verifiedSource: Cala RDH6524M1 specifications, Page 1 > Resistance elements Verified 2026-08-26; revalidation due before 2026-09-25. |
| ManufacturerRecirculation supported | Not found in reviewed sourcesSource: Cala RDH6524M1 specifications Verified 2026-08-26; revalidation due before 2026-09-25.Cala RDH6524M1 installation and operation manual Verified 2026-08-26; revalidation due before 2026-09-25.Cala Heat Pump Water Heater – RDH6524M1 Verified 2026-08-26; revalidation due before 2026-09-25. |
Certification and source record
Use the source links and dates to validate the exact model and current evidence before choosing.
| Source layer and field | Current source-backed status |
|---|---|
| ENERGY STARENERGY STAR source record ID | 4478534 Verified valueSource: ENERGY STAR certified-product dataset Verified 2026-09-01; revalidation due before 2026-09-04. |
| ENERGY STARENERGY STAR certification date | 2025-07-15 Verified valueSource: ENERGY STAR certified-product dataset Verified 2026-09-01; revalidation due before 2026-09-04. |
| ManufacturerManufacturer-listed certifications | ENERGY STAR, UL 60335-1, UL 60335-2-40, UL 174 Verified valueSource: Cala RDH6524M1 specifications, Page 1 > Certifications Verified 2026-08-26; revalidation due before 2026-09-25. |
Full technical facts and field-level evidence
ENERGY STAR certification fields
- ENERGY STAR ID
- 4478534
- Heat-pump type
- 240 Volt Integrated HPWH
- Fuel
- Electric
- Uniform Energy Factor
- 3.61
- Storage volume
- 65 gal
- First-hour rating
- 79 gal
- Listed annual electric usage
- N/A
- Input voltage
- 240 V
- Date certified
- 2025-07-15
Open the authoritative ENERGY STAR record (opens in a new tab)
Verified manufacturer fields
Each value below is tied to the exact model, retained source bytes, a field locator, and a current review interval. Dimensions do not include required clearances unless a clearance field is shown separately.
Identity
- Manufacturer Name
- Cala Systems, Inc Source: Cala technical specifications, Company footer; ENERGY STAR certified HPWH record 4478534, record 4478534 > specifications.brand_name
Physical
- Nominal Tank Capacity Gallons
- 65 gal Source: Cala RDH6524M1 specifications, Page 1 > Tank capacity
- Height Inches
- 67 in Source: Cala RDH6524M1 specifications, Page 1 > Product dimensions
- Diameter Inches
- 24 in Source: Cala RDH6524M1 specifications, Page 1 > Product dimensions
- Shipping Weight Pounds
- 287 lb Source: Cala RDH6524M1 specifications, Page 1 > Dry (Shipping) Weight
Electrical
- Input voltage
- 240 V Source: Cala RDH6524M1 specifications, Page 1 > Power; Cala RDH6524M1 installation and operation manual, Page 24 > Electrical; ENERGY STAR certified HPWH record 4478534, record 4478534 > specifications.input_voltage
- Phases
- 1 phase Source: Cala RDH6524M1 specifications, Page 1 > Power; Cala RDH6524M1 installation and operation manual, Page 24 > Electrical
- Recommended Breaker Amps
- 30 A Source: Cala RDH6524M1 specifications, Page 1 > Circuit; Cala RDH6524M1 installation and operation manual, Page 24 > Circuit breaker
- Circuit Requirement
- 240 V single-phase AC power with a 30 A double-pole breaker Source: Cala RDH6524M1 installation and operation manual, Page 24 > Circuit requirement
- Connection Type
- Hardwired through the unit junction box Source: Cala RDH6524M1 installation and operation manual, Page 27 > Electrical connection
Installation
- Allowed Location Types
- basement, garage, crawlspace, ventilated utility closet Source: Cala RDH6524M1 installation and operation manual, Page 14 > Installation location
- Top Clearance Inches
- 10 in Source: Cala RDH6524M1 installation and operation manual, Page 14 > Height clearance
- Floor Support Requirement
- Floor capable of supporting approximately 800 lb with the tank filled Source: Cala RDH6524M1 installation and operation manual, Page 13 > Floor support
- Orientation Requirement
- Install upright, vertical, and level Source: Cala RDH6524M1 installation and operation manual, Page 13 > Orientation
Performance
- Resistance Element Watts
- 4500 W Source: Cala RDH6524M1 specifications, Page 1 > Resistance elements
- Certifications
- ENERGY STAR, UL 60335-1, UL 60335-2-40, UL 174 Source: Cala RDH6524M1 specifications, Page 1 > Certifications
Modes
- Operating Modes
- Boost Mode Source: Cala RDH6524M1 installation and operation manual, Page 48 > Boost Mode
- Mode Descriptions
- Boost Mode: Temporarily increases hot-water capacity for expected heavier-than-normal usage; energy usage will be higher. Source: Cala RDH6524M1 installation and operation manual, Page 48 > Boost Mode
Sound
- Sound Test Context
- Internal Cala test based on NEEA v6.0 Appendix D at 55 Hz Source: Cala RDH6524M1 specifications, Page 1 > Sound test note
Ambient
- Minimum Operating Air Temperature Fahrenheit
- 37 °F Source: Cala RDH6524M1 specifications, Page 1 > Ambient operating range
- Maximum Operating Air Temperature Fahrenheit
- 120 °F Source: Cala RDH6524M1 specifications, Page 1 > Ambient operating range
- Operating Temperature Context
- Surrounding-air operating range published for the exact RDH6524M1 Source: Cala RDH6524M1 specifications, Page 1 > Ambient operating range
Ducting
- Ducting Supported
- Yes Source: Cala RDH6524M1 installation and operation manual, Page 29 > Ducting
- Inlet Duct Diameter Inches
- 8 in Source: Cala RDH6524M1 installation and operation manual, Page 29 > Air inlet
- Outlet Duct Diameter Inches
- 8 in Source: Cala RDH6524M1 installation and operation manual, Page 29 > Air outlet
- Maximum Equivalent Duct Length Feet
- 40 ft Source: Cala RDH6524M1 installation and operation manual, Page 31 > Maximum equivalent duct length
- Duct Configuration Notes
- No ducting is needed when any listed room/opening condition is met; otherwise the system may need ducting and the installer should determine the configuration. Source: Cala RDH6524M1 installation and operation manual, Page 15 > Room and ducting rules
Condensate
- Condensate Drain Required
- Yes Source: Cala RDH6524M1 installation and operation manual, Page 16 > Condensate drain
- Drain Connection Size Inches
- 0.75 in Source: Cala RDH6524M1 specifications, Page 1 > Condensate connection
- Drain Notes
- Route condensate to a nearby drain; if no suitable drain is available, a condensate pump may be necessary. Source: Cala RDH6524M1 installation and operation manual, Page 16 > Condensate routing
Features
- Documented Features
- variable-speed compressor, integrated flow sensor, integrated mixing valve, automatic leak detection, Wi-Fi connectivity, LPWAN connectivity, Bluetooth connectivity, Cala mobile app, upper and lower resistance elements Source: Cala RDH6524M1 specifications, Page 1 > Features
- Connectivity Supported
- Yes Source: Cala RDH6524M1 specifications, Page 1 > Connectivity
- Leak Detection Supported
- Yes Source: Cala RDH6524M1 specifications, Page 1 > Leak detection
- Demand Response Capable
- Yes Source: Cala RDH6524M1 installation and operation manual, Page 47 > Demand response
- Integrated Mixing Valve
- Yes Source: Cala RDH6524M1 specifications, Page 1 > Mixing valve
- Backup Resistance Elements
- Yes Source: Cala RDH6524M1 specifications, Page 1 > Resistance elements
Fields that cannot support a decision yet
- Physical Storage Volume Gallons: current official sources conflict.
- Electrical Frequency Hz: current official sources conflict.
- Performance Uniform Energy Factor: current official sources conflict.
- Performance First Hour Rating Gallons: current official sources conflict.
- Performance Annual Electric Usage Kwh: current verification is unavailable.
- Performance Maximum Setpoint Fahrenheit: current verification is unavailable.
- Sound Rated Sound Level Dba: current verification is unavailable.
Show 16 fields without a verified exact-model value
The reviewed sources did not provide an eligible value for these fields. Missing does not mean zero, false, not required, or compatible.
- Identity Model Family Name: N/A.
- Identity Model Aliases: N/A.
- Physical Width Inches: N/A.
- Physical Depth Inches: N/A.
- Physical Empty Weight Pounds: N/A.
- Electrical Minimum Circuit Ampacity Amps: N/A.
- Electrical Maximum Overcurrent Protection Amps: N/A.
- Installation Minimum Room Volume Cubic Feet: N/A.
- Installation Side Clearance Inches: N/A.
- Installation Front Service Clearance Inches: N/A.
- Installation Rear Clearance Inches: N/A.
- Installation Seismic Anchoring Requirement: N/A.
- Performance Recovery Rate Gallons Per Hour: N/A.
- Performance Heat Pump Capacity Btu Per Hour: N/A.
- Condensate Condensate Pump Included: N/A.
- Features Recirculation Supported: N/A.
Reviewed sources
- Cala Heat Pump Water Heater – RDH6524M1 Verified 2026-08-26; revalidation due before 2026-09-25.
- Cala RDH6524M1 installation and operation manual Verified 2026-08-26; revalidation due before 2026-09-25.
- Cala RDH6524M1 specifications Verified 2026-08-26; revalidation due before 2026-09-25.
- Cala technical specifications Verified 2026-08-26; revalidation due before 2026-09-25.
- ENERGY STAR certified HPWH record 4478534 Verified 2026-09-01; revalidation due before 2026-09-04.