Carrier 48JZ Operating And Maintaining Manual

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A Guide to Operating and Maintaining Your
Single-Packaged Gas Heat/Electric Heat Pump Unit
NOTE: Read the entire instruction manual before starting the
installation.
SAFETY CONSIDERATIONS
Note to Installer: This manual should be left with the equipment
user.
Do not store or use gasoline or other flammable vapors and
liquids in the vicinity of this or any other appliance. Failure to
follow this warning could result in fire, serious injury, or
death.
Do not use this unit if any part has been under water.
Immediately call a qualified service technician to inspect the
unit and to replace any part of the control system which has
been under water. Failure to follow this warning could result
in electrical shock, fire, serious injury, or death.
Before performing recommended maintenance, be sure the
main power switch to unit is turned off and lock-out tag
installed. Electric shock could cause serious injury or death.
UNIT INTRODUCTION
This 48JZ unit is a small packaged gas heat/electric heat pump
system that can utilize both the efficiency of heat pump heating
and the comfort of gas heating. The system will optimize for ideal
heating, depending on several factors. This unit uses Puron®, the
ozone friendly refrigerant for cooling and heat pump heating.
Starting or Shutting Unit Off
1. To start the unit:
a. Turn on the electrical and gas power supply to unit.
b. Select temperature and set SYSTEM switch or MODE
control to desired mode.
2. To shut unit off:
NOTE: If the unit is being shut down because of a malfunction,
call your dealer as soon as possible.
a. Set system SWITCH or MODE control to OFF.
b. Turn off the electrical power, install lock-out tag and shut
off gas supply to unit.
OPERATING YOUR UNIT
The operation of your system is controlled by the indoor tempera-
ture control (for 48JZ, either a Thermidistat™ or dual fuel
thermostat is required). You simply adjust the thermostat and it
maintains the indoor temperature at the level you select. Most
thermostats of heating and cooling systems have 3 controls: a
temperature control selector, a FAN control, and a SYSTEM or
MODE control. Refer to your thermostat owner's manual for more
information.
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
PC 101 Catalog No. 534–80084
Single-Packaged Gas Heat/Electric Heat Pump
Unit with Puron (R-410A) Refrigerant
Printed in U.S.A. Form OM48–15
Fig. 1—Unit 48JZ
To better protect your investment and to eliminate unnecessary
service calls, familiarize yourself with the following facts:
1. During heat pump heating, increasing the thermostat setting
more than 2°F may cause the supplemental gas heat to be
turned on for a short period of time to satisfy the thermostat.
Needless use of the supplementary heat reduces potential
energy savings.
2. Ice or frost tends to form on the coil during winter heating
operation. Your heat pump is designed to automatically melt
the ice. When in this defrost cycle, it is normal for steam or
fog to rise from the outdoor unit. Do not be alarmed!
Step 1—Cooling Mode
With the SYSTEM or MODE control set to COOL, your unit will
run in cooling mode until the indoor temperature is lowered to the
level you have selected. On extremely hot days, your unit will run
for longer periods at a time and have shorter "off" periods than on
moderate days.
Step 2—Heat Pump Heating Mode
With the SYSTEM or MODE control of your indoor thermostat set
to HEAT, your unit will run in heat pump heating mode until room
temperature is raised to the level you have selected. Of course,
your system will run for longer periods to maintain a comfortable
environment on cooler days and nights than on moderate ones.
Step 3—Gas Heat Mode
Your heat pump is your primary heating source. Your system is
also be equipped with a supplemental gas heating source. On cold
days and nights, your system will automatically turn on the
supplemental heat in order to maintain the level of comfort you
have selected.
Pg 1
48JZ
C99088
10–01 Replaces: New