Condenser heat recovery shall be installed for heating or reheating of service hot water provided the facility operates 24 hours a day, the total installed heat capacity of water-cooled systems exceeds 6,000,000 Btu/hr (1 758 600 W) of heat rejection, and the design service water heating load exceeds 1,000,000 Btu/h (293 100 W).
The required heat recovery system shall have the capacity to provide the smaller of:
- Sixty percent of the peak heat rejection load at design conditions; or
- The preheating required to raise the peak service hot water draw to 85°F (29°C).
Exceptions:
- Facilities that employ condenser heat recovery for space heating or reheat purposes with a heat recovery design exceeding 30 percent of the peak water-cooled condenser load at design conditions.
- Facilities that provide 60 percent of their service water heating from site solar or site recovered energy or from other sources.