Unit 45
What is radon?
A naturally occurring radioactive gas sometimes found in basements and crawl spaces.
What type of unit is a PTAC?
Single phase and AC power unit.
What is the range of unitary equipment size?
Small fractional tonnage room coolers to large packages rooftop units in the 100ton category.
How is the energy efficiency ratio, EER calculated?
Taking the output in BTU/hr and dividing it by the input in watts.
Unitary air conditioning equipment consists of one or more factory made assemblies, which normally include an evaporator or cooling coil, a compressor and condenser combination and possibly a heating unit. True or False?
True
What is a console through the wall conditioner?
Type of room cooler that is designed for permanent installation.
What are residential air conditioning system often made up of?
Unitary air conditioning components.
What is a front desk control interface on a PTAC?
Units may be individually started and stopped with an energy management panel from a central location.
A stand alone air conditioner unit is mainly for what use?
Residential use
What type of compressor is in most PTAC units?
Rotary compressors
The PTAC EER is equal to the cooling output in BTU/hr divided by the power input in watts under standard rating conditions. True or False?
True
What is the standard rating conditions set up by AHRI for PTAC?
80 degree F db, 67 degree F wb for the indoor entering air, and 95 degree F db for the outdoor air.
What is the PTAC range at standard rating conditions?
6,800 BTU/hr to 14,900 BTU/hr
What available voltage is for PTAC units?
1. 115 V 2. 208/230 V
What applications are required for a stand alone air conditioning unit?
1. Air handler outfitted with an evaporator coil. 2. Metering device 3. Drain pan 4. Transformer 5. Blower assembly 6. Housing
What are the kit of parts for installation for room air conditioners?
1. Sill brackets 2. Window mounting strips 3. Sealing strips
What are major disadvantages of a stand alone air conditioning unit?
1. Type of condenser 2. Location of condenser
What are the 3 configurations of the air handler for stand alone air conditioning units?
1. Vertical up flow 2. Vertical down flow 3. Horizontal
What voltage do smaller window units operate on?
115V
What voltage do larger window units operate on?
230/208 V
What is the quantity of outside air that the PTAC unit can admit?
40 CFM to 55 CFM
What is the typical size range for window air conditioning units?
5,000 BTU/hr to 20,000 BTU/hr
What is a disadvantage for room air conditioners?
Block part of the window area and prevent the window from being opened or require a special hole through the wall.
What type of metering device is in most PTAC units?
Capillary tubes metering device
What is the outside air damper for PTAC?
Control lever can be positioned to permit zero for fully open supply of outside air.
What are unitary air conditioning systems?
Factory built and tested systems, complete as much as possible, with piping, controls, wiring, and refrigerant.
The higher the EER rating, the worse the efficiency. True or False?
False, the higher the EER rating, the better the efficiency.
What's a disadvantage of a room air conditioner?
May either block part of the window area and prevent the window from being opened or require a special hole through the wall.
What are console through the wall conditioners also know as?
Packaged terminal air conditioners, PTAC
What does the the motor shaft extend through?
The separating partition and drives both fans.
An electric heat capacity from 1.5 kW to 5.0 kW can be installed in any console through the wall units. True or False?
True
Condensate from the evaporator coil flows into the drain pan, which extends below the condenser fan. The condenser fan tip dips into condensate, splashing it onto the hot condenser; where it evaporates and is blown into the outside air. True or False?
True
One of the motors of the room air conditioner operates both the indoor blower and outdoor fan. True or False?
True
What happens on the inside section of room air conditioner?
the evaporator fan draws in room air through the filter and cooling coil, delivering conditioned air back inside. Where the condenser fan forces outside air through the condenser.
