Manufacturer of Quality Air Conditioning and Heating Products • www.islandaire.com • sales@islandaire.com • (800)-886-2759
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Dr.PTAC information
The Dr. PTAC system is an add on system to our standard PTAC unit to provide conditioned makeup air into a space thru
the PTAC unit by providing up to 55 CFM of outdoor air 24/7 by forced fan and cycling dehumidifier compressor based on
outdoor relative humidity levels.
Dr. PTAC was created to solve issues with dehumidification in rooms and to introduce fresh air due to deficiencies of
oxygen levels. Dr. PTAC is not only a PTAC but a Conditioned Make Up Air unit. New ASHRAE studies show that many
illnesses in hotel rooms can be attributed to oxygen deficient atmospheres. Dr. PTAC solves that issue by introducing tem-
pered conditioned make up air that satisfies both humidity level introduction and supplied oxygen.
Dr. PTAC is a two-stage system. The primary unit is responsible for control of Sensible Heat that is introduced into the
room via make up air temperature and thermal load of the occupants. The secondary unit is primarily a dehumidifica-
tion unit that provides up to 55 CFM of outside fresh air into the room. The correction of the Sensible Temperature comes
from the main PTAC unit, which provides additional dehumidification with temperature correction. Overall unit effi-
ciency over standard PTAC’s is approximately 3% improvement. The compressor/dehumidification process is controlled by
a humidistat (factory set at 50% RH), which is monitoring the outdoor relative humidity level and is adjustable by a quali-
fied servicer. When the outdoor humidity level raises above 50% RH, the compressor and dehumidification process starts.
Below 50% RH, compressor operation and dehumidification is stopped, however, fan operation continues to provide up to
55 CFM of outdoor air into the space.
The dehumidification system has a temperature switch which is monitoring both the refrigeration and the outdoor air
temperatures. If the outdoor air goes below 38 °F, the compressor is disabled with fan operation continuing to provide
outdoor air into the space. All dehumidifier controls and safeties are automatically reset. An optional air tempering heater
is available for the fresh air system for applications where operation in cold winter climates is required. Condensate from
the dehumidifier drains into the PTAC drain pan, where it is also slung onto the condenser coil for re-evaporation outside
when the A/C runs. Excess condensate is drained into the wall case, which can then either drain to the outside through the
louver OR is piped to a drainage system via an optional drain kit.
ADVANTAGES OF ThE DR. pTAC SYSTEm:
1. Lower installation/renovation costs than typical DOAS*
2. Decreased inconvenience to customer due to construction/installation of a DOAS* system
3. More humidity control in a room over use of a simple PTAC vent or Power vent system
4. Allows fresh make up air to travel entirely across sleeping and living areas of a room, exiting through a duct or under
the door
*DOAS = Dedicated Outdoor Air System
