Trane OABE OADE OAKE OANE (Water Source Heat Pump) Katalog

OAU-PRC003A-EN

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the outdoor air, use the optional total-energy wheel to recover energy from building exhaust.

One way to control an energy recovery device is to turn it on and off with the OAU system 
exhaust fan. In this case, the total energy wheel enables when the unit is in occupied mode and 
the exhaust fan is running. While this control method is certainly simple and effective in some 
applications, it may not provide the expected energy saving benefit, particularly when cold air 
(vs. neutral air) is supplied to the building.

Another more effective approach is to use the outdoor air dry-bulb to determine when to ener-
gize or de-energize the energy recovery device. See 

 for an example of this simpli-

fied control. In addition to being more effective from a control standpoint, it’s also a very simple 
control method because the wheel is enabled when all of the following are true:

•

unit is in occupied mode, 

•

exhaust fan is enabled, 

•

Unit Main Control Module (MCM) calls for unit to operate in dehumidification, cooling, or 
heating modes, and 

•

outside air temperature is above the frost protection setpoint (default setpoint 12°F). 

If using the OAU to deliver cold, dry conditioned air to the building (outdoor air is cooled to a low 
dew point but not reheated), use the cooling setpoint control strategy (see