Retrotec USACE - Manual (Page 170)

D40 ENERGY & PROCESS ASSESSMENT PROTOCOL
Control systems that need repair and calibration can be identifi ed by their
actions—for example,
Dampers that are open more than required during extreme outdoor ■
weather conditions
Systems that do not shut down or start in a timely manner
■
The presence of heat to the system when not necessary ■
System alarms that go unchecked. ■
D.2.5.2 Simultaneous Heating and Cooling (Waste)
Figure D65. Heating and cooling the space at
the same time.
Simultaneous heating and cooling (Figure D65) defeats the purpose of either
heating or cooling an occupied space. The energy used to heat a space is offset
by the energy used to cool it. Controls should be used to lock out the ability to
heat when cooling is being used, and vice versa.
D.2.5.3 Heating or Cooling Unused Spaces (Waste)
Heating or cooling is typically done to provide occupant comfort. Sometimes
equipment or processes require heating or cooling for specifi c needs, and
buildings may require heating to prevent freezing of liquids stored in pipes
or containers. However, when spaces are unoccupied and equipment or pro-
cesses requirements are not involved, heating or cooling can be eliminated.
Eliminating heating or cooling will reduce or eliminate the energy associated
with comfort conditioning during unoccupied time.
D.2.5.4 Not Using Free Cooling (Waste)
Cooling during winter months can use outdoor air to replace traditional air
conditioning resources and refrigeration to condition the occupied space. This
can be done by using the ventilation outdoor air intake. Outdoor air is brought
directly into the spaces to be cooled, such as an interior space, and mixed with
return air to satisfy a supply air temperature. Care should be taken that the
temperature of the ventilation outside air is above 0 °C (32 °F) so that existing
water coils will not be frozen.