6
ACCESSORY USAGE GUIDELINE
ACCESSORY
REQUIRED FOR LOW---AMBIENT
COOLING APPLICATIONS
(Below 55
°
F/12.8
_
C)
REQUIRED FOR
LONG LINE
APPLICATIONS*
(Over 80 ft. / 24.4 m)
REQUIRED FOR
SEA COAST APPLICATIONS
(Within 2 miles / 3.2 km)
Compressor Start Assist Capacitor and Relay
Yes
Yes
No
Crankcase Heater
Yes
Yes
No
Evaporator Freeze Thermostat
Yes
No
No
Hard Shutoff TXV
Yes
Yes
Yes
Liquid Line Solenoid Valve
No
See Longline
Application Guideline
No
Low---ambient Control
Yes
No
No
Winter Start Control
Yes
No
No
* For tubing line sets between 80 and 200 ft. (24.38 and 60.96 m) and/or 35 ft. (10.7 m) vertical differential, refer to Residential Piping and Longline Guideline.
Accessory Description and Usage (Listed Alphabetically)
1. Crankcase Heater
An electric resistance heater which mounts to the base of the
compressor to keep the lubricant warm during off cycles.
Improves compressor lubrication on restart and minimizes the
chance of liquid slugging.
Usage Guideline:
Required in low ambient cooling applications.
Required in long line applications.
Suggested in all commercial applications.
2. Evaporator Freeze Thermostat
An SPST temperature--actuated switch that stops unit operation
when evaporator reaches freeze--up conditions.
Usage Guideline:
Required when low ambient kit has been added.
3. Low--Ambient Control
A fan--speed control device activated by a temperature sensor,
designed to control condenser fan motor speed in response to the
saturated, condensing temperature during operation in cooling
mode only. For outdoor temperatures down to --20
_
F (--28.9
_
C),
it maintains condensing temperature at 100
_
F
±
10
_
F (37.8
_
C
±
5.5
_
C).
Usage Guideline:
A Low Ambient Controller must be used when
cooling operation is used at outdoor temperatures
below 55
_
F (12.8
_
C).
Suggested for all commercial applications.
4. Outdoor Air Temperature Sensor
Designed for use with Payne Thermostats listed in this
publication. This device enables the thermostat to display the
outdoor temperature. This device also
is required to enable special thermostat features such as auxiliary
heat lock out.
Usage Guideline:
Suggested for all Payne thermostats listed in this
publication.
5. Thermostatic Expansion Valve (TXV)
A modulating flow--control valve which meters refrigerant liquid
flow rate into the evaporator in response to the superheat of the
refrigerant gas leaving the evaporator.
Kit includes valve, adapter tubes, and external equalizer tube.
Hard shut off types are available.
NOTE
: When using a hard shut off TXV with single phase
reciprocating compressors, a Compressor Start Assist Capacitor
and Relay is required.
Usage Guideline:
Accessory required to meet ARI rating and system
reliability, where indoor not equipped.
Hard shut off TXV or LLS required in air conditioner
long line applications.
Required for use on all zoning systems.
6. Time--Delay Relay
An SPST delay relay which briefly continues operation of indoor
blower motor to provide additional cooling after the compressor
cycles off.
NOTE
: Most indoor unit controls include this feature. For those
that do not, use the guideline below.
Usage Guideline:
Accessory required to meet ARI rating, where indoor
not equipped.
7. Winter Start Control
This control is designed to alleviate nuisance opening of the
low--pressure switch by bypassing it for the first 3 minutes of
operation.
PA
13N
AZ