Johnson Controls MR4PMUHV User Manual

Product/Technical MR4PMUHV
Issue Date July 25, 2002
© 2002 Johnson Controls, Inc. 1
Part No. 24-8790-18, Rev. D www.johnsoncontrols.com
Code No. LIT-125190
MR4PMUHV Electronic
Temperature/Defrost Control with Relay Pack
The MR4PMUHV Temperature/Defrost Control with
Relay Pack controls the temperature and defrost
cycles on commercial refrigeration and freezer
applications. The control allows a hot gas or electric
heat defrost cycle and uses time or temperature to
control defrost termination.
The MR4PMUHV Temperature/Defrost Control
incorporates temperature management, defrost
management, evaporator fan management, and alarm
management control functions. One convenient
package consolidates the functions of a thermostat, a
digital display, a timer, and a defrost termination
switch.
Figure 1: MR4PMUHV Electronic
Temperature/Defrost Control with Relay Pack
Features and Benefits
 Single Package
Provides the functionality of multiple control
components at a cost-effective price.
 Easily Readable Display
Displays main sensor or auxiliary sensor
temperatures; helps troubleshoot system.
Provides alarm codes.
 Accurate, Interchangeable
Temperature Sensor
Provides accurate control performance with up to
300 feet (91 m) of sensor wiring. (A temperature
offset function may be set to accommodate
applications with longer sensor wire leads.)
 Heavy-Duty Relays
Allow direct control of compressors, fans, and
heaters. Reduce installation time.
 Nonvolatile Memory
Retains user-programmed settings in event of
power loss.
 Alarm Management
Functions
Provide alarm codes and a relay to either
operate a remote alarm or trigger a dial-out
modem.

Johnson Controls MR4PMUHV Specifications