Carrier 48MA - Manual

Number One
AirConditbning
Maker
Carrier Parkway • Syracuse, N Y 13201
Packaged Rooftop Multizone Units
DX Cooling/Natural or LP Gas, Electric or Hot Water/Glycol Heat
....
i - x
mm
CONTENTS
Page
INTRODUCTION I
PHYSICAL DATA 2
CONSTRUCTION 3
General 3
Electrical - 3
Refrigeration System 3
Heating 5
SYSTEM SELECTION AND OPERATION 7
APPLICATION 10
Diversity 10
Limitations 10
Reheat Applications 11
Economizer 11
Economizer and Exhaust Performance 14
Economizer Economics 15
Night Setback 16
MISCELLANEOUS 19
Sound and Vibration 19 ■;
Thermostat Usage and Control 20
Return Air Systems 20
RATING TABLES 30-41
FAN PERFORMANCE 42
Pulley Selection 42
Balancing Dampers 42
Performance Table 43
HEATING PERFORMANCE 46
Electric 46
Gas 46
Hot Water/Glycol 47
ELECTRICAL DATA 48-52
Power Wiring 52
INTRODUCTION
The Carrier 48MA/50ME modular multizone
differs markedly from the traditional hot deck/
cold deck reheat multizone. Carrier’s packaged
rooftop units do not employ the hot deck/cold
deck principle or the zoning dampers associated
with conventional units.
Carrier’s distinctive design — individual modules
for heating and/or cooling with constant module
airflow, is a true innovation to the multizone
market. The modular units heat, cool or de-
humidify in each module simultaneously and
independently of all other modules. Modules can
serve individual zones or be grouped together to
serve larger zones.
The modular multizones are available in 6 sizes
based on cooling capacity.
Capacity No. of Unit
(tons) Modules Designation
15 8 48MA/50ME016
20 8 48MA/50ME024
25 10 48MA/50ME028
28 5 10 48MA/50ME030
30 12 48MA/50ME034
37 12 48MA/50ME040
LP or natural gas, electric resistance or hot
water/glycol heating options are available to maxi­
mize efficient use of local energy resources. Econo-
mizers,
power exhaust, roll filters and
high-efficiency filters are also available as factory
installed
options - all providing a greater
flexibility in applying the modular multizone to
specific job requirements.
A recent multizone energy study compared the
energy usage of the Carrier modular units with 3
competitive designs. The study simulated (by
computer) the operation of the units for one year
in a typical building in each of 14 major U.S. cities.
The cities represented complete coverage of the
climatic conditions experienced throughout the
country. Study results showed the Carrier multi­
zone consumed less energy than the others in each
case considered under all climatic conditions.
Details of the energy study are contained in the
Carrier brochure, The Modular Multizone Versus
the Others.
© Carrier Corporation 1976 Form 50ME-1XA