INTRODUCTION……………………………………………………………………………………………..3
WARNING LABES AND SAFETY INSTRUCTIONS…………………………………………………….4
MRS SERIES CONDENSING UNIT FEATURES………………………………………………………...5
MRS POD SYSTEM NOMENCLATURE…………………………………………………………………..6
MRSW POD SYSTEM NOMENCLATURE………………………………………………….…………….7
PRE-INSTALLATION INSTRUCTIONS…………………………………………………………….……..8
General Information…………………………………………………………………………………….…………8
Delivery Inspection………………………………………………………………………………………….….…8
Handling and Placement of Multiple Rack System…………………………………………………………....8
Handling and Placement of Walk-In Evap(s)………………………………………………………………...…8
Electrical Specifications………………………………………………………………………………………. …9
Refrigerant Piping……………………………………………………………………………………………..…10
Suction and Liquid Line Sizes………………………………………………………………………..……..11-12
Leak Check…………………………………………………………………………………………………….…13
Evacuation, Dehydration, and Start-Up………………………………………………………………….....…13
MRS/MRSW START-UP DATA TABLE………………………………………………………..…...…40
2
Page 3
INTRODUCTION
Thank you for purchasing Master-Bilt refrigeration equipment. This manual contains important instructions for
installation, use and service. Read this entire manual carefully before installing or servicing your Master-Bilt equipment.
NOTICE
Installation and service of the refrigeration and electrical components must be preformed by a refrigeration
mechanic or licensed electrician.
DANGER
Equipment MUST be properly grounded.
Improper or faulty hook-up of electrical components of the refrigeration units can result in severe injury or
death. All electrical wiring hook-ups must be done in accordance with all applicable local, regional or national
standards.
NOTICE
Read this manual before installing your refrigeration equipment. Keep the manual and refer to it before doing
any service. Failure to do so could result in personal injury or equipment damage.
The portions of this manual covering refrigeration and electrical components contain technical instructions intended only
for persons qualified to perform refrigeration and electrical work.
This manual cannot cover every installation, use, or service situation. If you need additional information, call or write us:
Parts and Technical Service Department
Master-Bilt Products
908 Highway 15 North
New Albany, MS 38652
Phone (800) 684-8988
Email: service@master-bilt.com
3
Page 4
WARNING LABELS AND SAFETY INSTRUCTIONS
This is the safety-alert symbol. When you see this symbol, be alert to the potential forpersonal injury or
damage to your equipment.
Be sure you understand all safety messages and always follow recommended precautions and safe operating practices.
NOTICE TO EMPLOYERS
You must make sure that everyone who installs, uses, or services your refrigeration equipment is thoroughly
familiar with all safety information and procedures.
Important safety information is presented in this section and throughout the manual. The following signal words are
used in the warnings and safety messages:
DANGER: Severe injury or death WILL occur if you ignore the message.
WARNING: Severe injury or death CAN occur if you ignore the message.
CAUTION: Minor injury or damage to your refrigeration can occur if you ignorethe message.
NOTICE: This is important installation, operation or service information. If you ignore the message, you may
damage your refrigeration.
The warning and safety labels shown throughout this manual are placed on your Master-Bilt Products
refrigeration at the factory. Follow all warning label instructions. If any warning or safety labels become lost or
damaged, call your customer service department at (800) 684-8988 for replacements.
This Label is located on the condensing unit
4
Page 5
MRS SERIES CONDENSING UNIT FEATURES
•Generously sized individual copper aluminum condenser for each compre ssor sized for high efficiency. Sized to
operate efficiently in high Ambient
• Hermetic, semi-hermetic, and Scroll compressors in any combination the customer chooses
• Reliable Ball Bearing Fan Motors
• Spring Mounted Semi-Hermetic Compressors, Hermetic and Scroll Compre ssors use Vibration Absorbing
Grommet Mounts
• Generously sized receivers with isolation valves
• Compressor Suction Service Valves with Access Ports, and Discharge Line Service Valves with Access Ports
on Semi- Hermetic Compressors only
• Pre-wired and mounted Dual Pressure Controls with each Compressor
• Units leak and electrical tested
• U.L. listed
• Easy accessibility for service
• Pre-wired for easy installation with Single Point Electrical Connection with individual Circuit Breakers for each
Compressor and Through Door Main Disconnect Switch and Circuit Breaker Installed
• Suction and discharge line vibration eliminators pre-piped and mounted (semi-hermetic only)
• Crankcase Heater Installed for each Compressor
• Refrigeration line pre-piped to edge of unit
• Pre-piped and mounted refrigerant sight glass and filter drier
• Pre-installed inverted traps on all roof top MRS series Condensing units
• Flooded Head Pressure Controls on each System
• Stainless Steel Housing
• Engineered Refrigeration Drawing Available for Specified Projects, or with Purchase Order (Contact Factory for
Additional Details
•Master-Controller Electronic Refrigeration Controls for Maximum Energy Efficiency are Optional for most
Systems. Patented Reverse Cycle Defrost Technology that saves up to 27% on Operational Energy Cost of the
System it Controls Depending on Ambient Temperatures.
5
Page 6
A
MRS POD SYSTEM NOMENCLATURE
C C H X OO5 B
C = Master-Bilt Rack System
Compressor Type Voltage Code
C = Semi-Hermetic
D = Discuss B = 208-230/60/1 V
H = Hermetic C = 208-230/60/3
S = Scroll D = 460/60/1
Temperature Range
H = High/Medium
M = Medium
L = Low (-40 - -25 )ºF
Refrigerant TypeOO5 =1/2HP
X = R-22 OO7 =3/4 HP
Z = R404a O1O =1 HP
System Capacity (Horsepower)
OO3 =1/3 HP
O15 =1 1/2 HP
O2O =2 HP
O3O =3 HP
O4O =4 HP
O5O =5 HP
O6O =6 HP
O75 =7 1/2 HP
O9O =9 HP
1OO =10 HP
C = Semi-Hermetic B = 208-230/60/1
D = Discuss C = 208-230/60/3
H = Hermetic D = 460/60/1
S = Scroll E = 460/60/3
Temperature Range
H = High/Medium
M = Medium OO31/3 HP
L = Low (-40 - 25 )ºF OO5 =1/2 HP
Refrigerant Type
X = R-22 O15 =1 1/2 HP
Z = R404a O2O =2 HP
Voltage Code
= 115/60/1
System Capacity (Horsepower)
OO7 =3/4 HP
O1O =1 HP
O3O =3 HP
O4O =4 HP
O5O =5 HP
O6O =6 HP
O75 =7 1/2 HP
O9O =9 HP
1OO =10 HP
7
Page 8
PRE-INSTALLATION INSTRUCTIONS
I. GENERAL INFORMATION
Please read this manual prior to installing your Master-Bilt equipment. This information is based on good refrigeration
practice and should be used as a guide for installation and operation.
II.
DELIVERY INSPECTION
You are responsible for filling all freight claims with the delivering truck line. Inspect all cartons and crates for damage
as soon as they arrive. If damage is noted to shipping crates or cartons or a shortage is found, note this on the bill of
lading (all copies) prior to signing.
If damage is discovered when the cabinet is uncrated, immediately call the delivering truck line and follow up the call
with a written report indicating concealed damaged to your shipment. Ask for an immediate inspection of your
concealed item. Crating material MUST be retained to show the inspector representing the truck line.
INSTALLATION INSTRUCTIONS
I.
HANDLING AND PLACEMENT OF MULTIPLE RACK SYSTEM
To minimize damage to the unit housing, it is recommended that the crate not be removed until the rack system is
moved to its final location.
There should be a minimum of 3 feet around the perimeter of the Rack System that should be unobstructed.
This allows for proper air flow through the condenser. Likewise, this will also make servicing the equipment
much easier.
Holes are provided in the base supports for mounting bolts and for bridle lift rods.
For indoor mounting, motor rooms should be provided with fans designed to move 100 CFM of air per one ton of
refrigeration capacity.
II. HANDLING AND PLACEMENT OF WALK-IN EVAP(S)
To minimize damage to the evaporator coil, it is recommended that the carton (or crate) not be removed until the
evaporator coil is moved close to its final location. When the container is removed from the evaporator coil, extreme
care must be used when lifting and mounting to the ceiling, to prevent sheet metal damage
Evaporator coils will be mounted the appropriate distance from the cooler wall to allow proper air return to evaporato r
coils. Minimum distance shall be greater than or equal to the vertical height of the evaporator coil or as specified in
applicable Installation and Operation Manuals.
8
Page 9
III. ELECTRICALSPECIFICATIONS
Electrical power supply must match the condensing unit
power requirements indicated on the unit data plate. A
WIRING DIAGRAM IS LOCATED ON THE INSIDE ON
THE ELECTRICAL BOX COVER. For best results, it is
suggested that power supply for MRS Rack systems be
applied as illustrated below in Figure 1. All field wiring
should be done in a professional manner, in accordance
with all governing codes. All wiring (including factory
terminals) should be double checked before start-up
The refrigeration installer will be responsible for the interconnect wiring between Medium temperature timers and
solenoids and Low temperature evaporators and timers.
MASTER-BILT WILL GLADLY SHIP ANY TIMER LOOSE
WITH PROPER ENCLOSURE SO THAT THEY MAY BE
PLACED
IN A MORE SUITABLE LOCATION IF REQUESTED
AND APPROVED BY FEC OR CONSULTANT.
Figure 1: Suggested Field Wiring Location for MRS Units.
Evaporator drain line heaters will be installed on any application with a room temperature less than 34ºF. A 6 ft. drain
line heater (208-230V) will be provided with each low temperature coil.
NOTICE!
Systems with scroll compressors must be checked for proper power phasing. Improper power phasing will result in
improper compressor rotation causing compressor to pump incorrectly. An optional phase monitor may be purchased
for this purpose.
Three phase scroll compressors are directional dependent, i.e., they will only compress in one rotational direction and
will rotate in either direction depending on power phasing. Verification of proper rotational direction is made by
observing that suction pressure drops and discharge pressure rises when the compressor is energized. Reverse
rotation also results in an elevated
compared to data tag values.
NOTICE!
Check phase alignment on all incoming power.
sound level over correct rotation, as well as substantially reduced current draw
9
Page 10
IV. REFRIGERANT PIPING
Use only refrigeration grade copper tubing, (ACR), type “L”, bright annealed, dehydrated, and properly se aled against
contamination. Soft temper tubing may not be used for field interconnection of refrigeration components (condensing
unit to evaporator assembly). Take extreme care to keep refrigeration tubing clean and dry prior to installation. Use an
appropriate size tube cutter. Remove any burring that may occur when cutting the tubing. Use dry nitrogen to purge the
system of any foreign objects that may have come about during any pipe cutting.
All suction lines will be insulated with not less than ¾” Armaflex or acceptable substitute as determined by Master-Bilt
personnel. Armaflex insulation must be properly glued or taped as approved by insulation manufacturer to prevent
refrigeration lines from “sweating”.
Appropriate oil must be added to systems with refrigeration line exceeding 50 ft horizontal or 10 ft vertical as per
Compressor manufacturer specifications.
Suction lines should be sloped down ½” for each 10 feet of horizontal run towards the compressor. This will facilitate
good oil return to the compressor.
Refrigeration lines will be sized appropriately to facilitate
proper oil return to the compressor and reduce refrigerant
line pressure drop. Table 1 and Table 2 depict proper line
sizing options. Use this as a guideline for your selection.
Any fittings used may be accounted for in the Table to the
right.
Fitting
Size90º Ell
1/2"0.9
5/8"1
7/8"1.5
1-1/8"1.8
1-3/8"2.4
1-5/8"2.8
2-1/8"3.9
TeeTee
45º Ell(Line)(Branch)
0.40.82
0.512.5
0.71.53.5
0.91.54.5
1.21.86
1.427
1.83.810
Equivalent Length Allowances for Pipe Fittings (length in feet)
All vertical risers will have an appropriate “P” trap at the beginning of the riser and every 20 ft above this point. If the
total rise is less distance than can be evenly divided by 20, the P-traps will be located at the beginning and in the cente r
of the distance so that the total distance between any two traps does not exceed 20 ft.
Keep the refrigeration lines as short as possible and use as few fittings as practicable, being especially careful not to
“kink” the lines. Keep the layout as simple as possible and properly support the piping to absorb vibration and the
normal expansion and contraction caused by temperature changes.
Liquid line filter driers, TXV, and solenoids will be installed on all systems that are single compressor per single
evaporator coil and Master-Bilt has provided the evaporator coil.
The TXV sensing Bulb must be properly mounted on the horizontal portion of the refrigerant suction line and properly
insulated. For systems with a suction line 7/8” OD or larger, surface temperature may vary slightly around the
circumference of the tube. Because of this, Sporlan recommends that sensing bulbs be mounted at the 4 or 8 o’clock
position. For smaller lines, the bulb may be mounted at any point (other than the bottom) on the horizontal suction
line.
Add appropriate amount of oil per compressor manufacturer recommendatio ns to compensate for longer refrigeration
line runs.
When brazing, dry nitrogen
the tubing and fittings. All flux will be removed from the joints when brazing is complete.
MUST be passed through the lines at low pressure to prevent scaling and oxidation inside
MINIMIZE the amount of flux used to prevent internal contamination of the refrigeration system.
Silver brazing wire is to be utilized (high temperature alloy of minimum of 5% silver content on all copper connections,
and high temperature alloy of 45% silver content on all dissimilar metal connections.
The refrigeration contractor will be responsible for providing and installing the liqu i d line solenoid valve and coil for all
systems where multiple evaporator coils are used or for “multiplexed” systems.
V.LEAK CHECK
When all refrigeration line connections have been made, the complete system, including fact ory connections, should be
checked.
Add the proper refrigerant to 60 psig, and then boost the 175 psig with dry nitrogen. Leak checks should be done on all
joints with an electronic leak detector or halide torch. If leaks are found, relieve the pressure and make repairs as
necessary and recheck.
VI. EVACUATION, DEHYDRATION, AND START-UP
A vacuum of 500 microns or less must be pulled to properly dehydrate the refrigeration system. This requires a twostage vacuum pump with an electronic vacuum indicator
Do not use the system compressor as a vacuum pump.
Do not operate compressor while system is in a vacuum.
.
13
Page 14
Evacuation Procedure
A. Open all condensing unit service valves and relieve system pressure. Also, open any line valves installed in the system
and energize all solenoid valves to facilitate evacuation.
B. Connect the vacuum pump to the high and low sides of the system using ¼” or larger copper lines or ¼” ID hoses with
high vacuum design.
C. Leaks or moisture will be i ndicated if the system pressure rises when the vacuum line is closed off.
Pull a vacuum of 1500 microns, close vacuum line and “break” vacuum to 5 psig, maximum, with refrigerant to be used
in the system.
E. Repeat step D.
F. A final vacuum of 250 microns should be pulled before charging. When 250 microns is reached, close vacuum line and
charge system with the proper refrigerant through the high side. See Table 4 (pp.17-19) for proper pre-charge for
respective pod. More refrigerant will be required depending upon the lengths of refrigeration lines required. Refer to
Table 5 for additional charge requirements for a given length of refrigeration line. Gradually add refrigerant until
recommended superheat values are obtained. (See Table 3 below)
NOTE: Never add liquid refrigerant to the suction side of the compressor.
Table 3
Applicable Temperature Recommended Superheat
Medium 6ºF - 12ºF
Low
5ºF - 10ºF
Finishing Charging Procedures
A. Preliminary
1. Be sure all service valves are “open”.
2. Loosen the compressor hold-down bolts and remove shipping clips to allow compressor to float freely on the springs.
(Semi-hermetic only)
3. Check evaporator fan motors, after start-up. Medium temperature, air defrost fans run continuously, low temperature
fans and coolers provided with electric defrost will be delayed by the fan control.
4. Check phase alignment of incoming power on all refrigeration systems as noted in the Electrical Specifications section
of this manual.
5. Start by “flipping on” the circuit breaker or circuit breakers in the unit electrical box.
6. Preset all room thermostats to the proper temperature.
7. Check operating pressures while charging and on initial pull down, to prevent damage if a problem occu rs. If system
“floods” back to the compressor, adjust thermostatic expansion valve as required for proper operation. There should be
at least +30º F superheat entering the compressor. Master-Bilt recommendations for superheat values seen at the
evaporator are given in Table 3.
8. For scroll compressors, verify power phasing and rotational direction as noted in the Electrical Specifications section of
this manual.
9. Observe compressor amperage draw and compare to compressor nameplate to prevent dam age due to high
amperage. The oil sight glass, when equipped, should be between ½ and ¾ full during normal operation.
14
Page 15
B. Low Ambient Charging Procedure
All standard air cooled condensers on the MRS Rack System are
equipped with a head pressure control valve to maintain proper head
pressure during winter conditions. These valves function by reducing
the effective condenser area by flooding or “backing up” refrigerant in
the condenser to reduce the amount of surface available for
condensing. To operate properly, more charge is required during this
flooding condition. This valve is not necessary when applying systems
with the Master Controller and winter charges are negligible. Please
contact our Customer Service Department for more about MasterController Technology.
To use the chart, multiply the pounds of recommended pre-charge
obtained by adding the recommended pre-charge (Table 4) with the
additional refrigerant required for line set length (Table 5) by the
percent flooding required in Chart A to arrive at the additional charge
required.
Typical Head Pressure Control Valve
15
Page 16
Chart A:
16
Page 17
Example of Low Ambient Charging
Determine the additional charge to operate a CHHX035C at suction temp +20ºF and the unit
is charged at +50ºF. Assume a 100 ft. line set (horizontal).
1. Capacity for CHHX035C @ +20ºF = 24,800 BTUH
2. Choose the proper refrigeration lines base on capacity from Table 1, suction line = 1 1/8”, liquid line = ½”.
3. Look up the recommended pre-charge from Table 4 for CHHX035C (8.5 lbs of R-22).
4. From Table 5, find the additional refrigerant (R-22 in this case) required for a ½” liquid line of length 100 ft.
(7.6 lb of R-22)
5. Add these two values to get 16.1 lbs of R-22.
6. Look at Chart A to obtain multiplier. The horizontal axis of Chart A yields the ambient charging temperature
(50º). The vertical axis of Chart A yields the multiplier. Notice there are several graphs in this chart. Select
the graph corresponding to your desired suction temperature. In this case, 20ºF. One can now see that the
condenser should be flooded at 32% to operate correctly.
7. Multiply 16.1 lbs of R-22 by 32% to get 5.15 lbs of additional charge.
8. Again, finish charging until desire superheat settings are obtained.
Master-BiltCompressor At Room Temp. With a 10° TD, 90° AmbientTank ConnectionsRecommendedRequired GPM
ModelModel-20-10020303540HP 90%/90°F Liquid Suction RLALRA Pre-Charge (lb) R-404A For a 10ºF TD
Master-BiltCompressor At Room Temp. With a 10° TD, 90° AmbientTank ConnectionsRecommendedRequired GPM
ModelModel-20-10020303540HP 90%/90°F Liquid Suction RLA LRA Pre-Charg e (lb) R-404A For a 10ºF TD
If you sell or give away your refrigeration equipment system or components you must make sure that all safety labels
and I&O Manuals are included. If you need replacement labels or manuals, contact the parts and technical service
department at Master-Bilt at (800) 684-8988
The customer service department at Master-Bilt should be contacted at the time of sale or disposal of your equipment
so records may be kept of its new location.
If you sell or give away your Master-Bilt cabinet and you evacuate the refrigerant charge before shipping, you must
evacuate the refrigerant into an approved recovery and reclaim system in order to satisfy all applicable federal and state
regulations regarding release of refrigerant compounds into the atmosphere.
The release of refrigerant compounds into the atmosphere is a source of ozone depletion and regulated by
state and federal laws.
LABOR WARRANTY
A. A 90 day labor warranty will be provided on all installer provided labor and installation.
B. A 1 year optional Labor warranty will be quoted separate from the installation.
C. Master-Bilt will provide a one year parts warranty on all parts that fail under normal operation conditions.