Airxcel Marvair LL357D4, Manual

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P/N 01661
Lead/Lag Controller
Model LL357D4
Operational Specifications
• Thermostat Range: 45ºF to 90ºF (7ºC
to 32ºC)
• Accuracy: ±1ºF (± ½ºC)
• Changeover Temperature Differential
(separation between the heat set
point and the cool set point): 2ºF to
9ºF (1.0ºC to 4.5ºC)
• First Stage Temperature Differential
(number of degrees between the set
point temperature and the “turn on”
temperature): 1ºF to 3ºF (.5ºC to
1.5ºC)
• Second Stage Temperature Differential
(number of degrees between when
stage 1 turns on and when stage 2
turns on): 1ºF to 6ºF (.5ºC to 3.0ºC).
• Minimum Cool Temperature Set Point:
Adjustable from 45ºF to 75ºF (7ºC to
24.0ºC).
• Maximum Heat Temperature Set
Point: Adjustable from 55ºF to 90ºF
(13ºC to 32.0ºC)
• Staged OFF Outputs: Air conditioners
will turn off independently.
Electrical Specifications
• Compatible with standard 24-volt AC,
2 stage heating/cooling systems.
• 24 Volt control (18 to 30 VAC).
• 1 amp maximum per terminal.
• 4 amp maximum total load.
Ease of Use
• Back lighting of the large display
makes the Liquid Crystal Display
(LCD) easy to read.
• Most frequently used keys are located
by the LCD for quick & easy access to
information.
• Easy installation, setup and system
tests saves time.
• Setpoints are permanently held in
memory and retained during power
outages - no batteries required.
• Programming not required.
• Digital display shows temperature in
°F or °C.
• Room Temperature Offset: Used to
calibrate displayed room temperature
with actual room temperature
• Status Indicator Light: Indicates which
stage is running. Green light means
cooling & red light means heating.
Model LL357D4 Lead/Lag Controller
The Marvair
®
LL357D4 is a complete control package
designed to operate a fully or partially redundant air
conditioning system. It consists of a two-stage heat and
cool electronic thermostat and a solid state timer. It
can be used with either the Marvair ComPac
®
I vertical
packaged wall mount air conditioner, our unique ComPac
®
II air conditioner with built-in economizer and many of the
Marvair Environmental Control Units (ECU). The LL357D4
provides environmental control and the security demanded
by the communication shelter industry for a back-up
unit. The lead/lag controller insures equal wear on both
air conditioners while allowing the lag unit to assist upon
demand. Phasing of air conditioners is not required for
proper operation. The environmentally safe, mercury-free LL357D4 is factory wired,
tested and mounted in an enclosure for quick installation. The LL357D4 when used
with the heat pump adapter, Model LL357H, provides control of redundant heat pump
systems. Refer to the Heat Pump Adapter Product Bulletin for details.
Specification/Features
LL357D4 PDS 4.2011 rev. 1