Commercial Water Heater Key Product Criteria
| Type | ENERGY STAR Requirements |
|---|---|
| Gas-fired Storage | > 75,000 BTU/hr input < 4,000 Btu/hr per gallon of stored water |
| Gas-fired Instantaneous | > 200,000 Btu/hr input ≥ 4,000 BTU/hr per gallon of stored water |
| Gas-fired Storage-type Instantaneous | Gas-fired Instantaneous with storage volume ≥ 10 gallons |
| Electric Heat Pump | > 12 kW rated electric power input |
| Criteria | Type | ENERGY STAR Requirements |
|---|---|---|
| Thermal Efficiency (TE) | Storage; Instantaneous |
TE >= 0.94 |
| Maximum Standby Loss [Btu/hr] | Storage | <= 0.84 * [(Input Rate / 800) +110(Volumer)1/2] |
| Storage-type Instantaneous |
| Criteria | Type | ENERGY STAR Requirements |
|---|---|---|
| Coefficient of Performance (COPh) | Commercial Heat Pump | COPh≥ 3.0 |
Optional Status and Messaging Features
While not required, the reporting of any system status and messaging features outlined below is encouraged for ENERGY STAR certification.
- Fault Detection and Display
- Performance Reporting
- Energy Savings Reporting
- Predictive Maintenance Alerts
Glossary
Thermal Efficiency (TE): The ratio of the heat energy (Btu/hr) transferred to the water flowing through the water heater to the amount of energy (Btu/hr) consumed by the water heater during full-firing rate, steady-state operation.
Coefficient of Performance (COPh): The dimensionless ratio of the rate of useful heat transfer gained by the water, expressed in Btu/h, to the rate of electrical power consumed during full input rate operation, expressed in Btu/h.
Standby Loss (SL): The average hourly energy, expressed in Btu per hour, required to maintain the stored water temperature based on a 70°F temperature differential between stored water and ambient room temperature.
Fault Detection and Display: System is capable of detecting and reporting, in plain text, system faults to the owner and/or technical professional. This includes, but is not limited to, the ability to detect leaks which may lead to catastrophic failure.
Performance Reporting: System is capable of reporting at least three system performance metrics. Examples of performance metrics include, but are not limited to, fuel usage, hot water usage, and run time.
Energy Savings Reporting: System is capable of analyzing performance in order to report energy saving opportunities capable of being addressed via maintenance, firmware updates, or operational changes.
Predictive Maintenance Alerts: System is capable of tracking water heater use and wear rates to predict and alert the owner/technical professional when maintenance may be required.
