Carrier 38AK - Manual

38AK,38AKS,38AQS008-012
48/50H J,48/50TJ,50LJQ008-014
Accessory Low Ambient Operation
Motormaster® III Control Package
50/60 Hz
Installation Instructions
Part Numbers: CAMOTOR3001AOO, CAMOTOR3002A00
CONTENTS
Page
SAFETY CONSIDERATIONS................................... 1
GENERAL .............................................................. 1,2
INSTALLATION......................................................2-16
Step 1 — Install Motor .............................................2
Step 2 — Install Motormaster III
Controller .............................................................. 3
Step 3 — Install Sensor ........................................... 3
Step 4 — Make Electrical Connections ................. 6
Step 5 — Install Field-Fabricated
Wind Baffies and Brackets.................................. 6
Step 6 — Restore Power to Unit.............................. 6
TROUBLESHOOTING .......................................... 17
SAFETY CONSIDERATIONS
Installation, start-up, and servicing of this equipment
can be hazardous due to system pressures, electrical com­
ponents, and equipment location (roofs, elevated struc­
tures, etc.)-
Only trained, qualified installers and service technicians
should install, start up, and service this equipment.
When working on this equipment, observe precautions in
the literature and on tags, stickers, and labels attached to
the equipment and any other safety precautions that may
apply.
A WARNING
Open all remote disconnects before servicing this equip­
ment. Electrical shock could result in personal injury.
GENERAL
This book contains instructions for the installation,
start-up, and service of the Motormaster III control on
38AKS008-012, 38AQS008, 38AK008-012, 48/50TJ008-
014, 48/50HJ008-014, and 50LJQ008,012 units. The
Motormaster III control is not used on 50-Hz versions of
the 50HJ008-014 and 50LJQ008,012 units.
NOTE: The Motormaster III control is not used on 48/50HJ
and 48/50TJ units with 2 condenser fans. The control is
used on single condensing fan units only.
The Motormaster III accessory is UL (Underwriters’ Lab­
oratories) and CSA (Canadian Standards Association)
approved on all split system and small rooftop electric cool­
ing and gas heating/electric cooling units.
The Motormaster III device is a motor speed control de­
vice which adjusts condenser fan motor speed in response
to declining liquid temperatures. A properly applied Motor-
master III control extends the operating range of air condi­
tioning systems and permits operation at lower outdoor am­
bient temperatures.
Table 1 shows the ambient temperature in cooling at which
each unit will operate without modification.
Table 1 — Unit Ambient Temperature Operation
UNIT
COMPRESSOR
CAPACITY
CONDENSER
TEMP
F(C)
MINIMUM
OUTDOOR
TEMP
F(C)
Small Rooftop Units
All 100% 90 (32) 25 (--1)
Split System Units
38AQS008 (60 Hz)
100% 90 (32) 55 (13)
38AK/AKS008
(50/60 Hz)
100% 90 (32) 60 (15)
38AKS009 (60 Hz) 100% 90 (32) 53 (12)
38AKS009 (50 Hz) 100% 90 (32) 57 (14)
38AKS012* 100% 90 (32) 48 (9)
(50/60 Hz) 67% 80 (27) 52 (11)
38AK012
(50/60 Hz)
100% 90 (32) 52 (11)
* Unit has one step of unloading.
To operate the units below the ambient temperatures in
Table 1, wind baffles and the Motormaster III control pack­
age must be added. The Motormaster III control permits
operation of the unit to an ambient temperature of -20 F
(-29 C) for small rooftop units, and 0 F (-18 C) for split
system units.
The Motormaster III regulates the speed of 3-phase fan
motors which are compatible with the control. These
motors are included in the package. See Tables 2 and 3 for
the contents of the Motormaster III accessory packages.
The CAMOTOR3001A00 package contains a motor for
208/230 volt, 60 Hz and 220 volt, 50 Hz applications. The
CAMOTOR3002A00 package contains a motor for 460
and 575 volt, 60 Hz and 400 volt, 50 Hz applications. See
Fig. 1.
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obiigations.
Book|1 |1 |1 |1 |4 |4 |4 |4 PC 111 Catalog No 533-803 Printed in U S A. Form 38/48/50-4SI Pg 1 1-95 Replaces: New
Tab la 1b 3a 5a 2a 5a 6a 6b