Zero Zone Highlight MERCHANDISER RHZC30 User manual

66-0032 • MN-18-B • SEP 2019
ZERO ZONE
HIGHLIGHT MERCHANDISER®
With CoolView®Doors & ChillBrite®LED Lighting
INSTALLATION & OPERATION MANUAL

III
Table of Contents
ZERO ZONE WARRANTY.....................................................................1
Limited Warranty .............................................................................1
Extended Warranties .......................................................................1
Length of Extended Warranty .........................................................1
Product Not Manufactured By The Seller .......................................1
Limitation and Exclusion of Warranties ...........................................1
INTRODUCTION....................................................................................2
Important User Information..............................................................2
Manufacturer....................................................................................2
Intended Use....................................................................................2
Display Case Models.......................................................................2
INSTALLATION & OPERATION............................................................4
Delivery Inspection...........................................................................4
Packaging........................................................................................4
Location...........................................................................................4
Leveling............................................................................................4
Setting the Case..............................................................................5
Moving Cases..................................................................................5
LineupAssembly..............................................................................6
Drain Line.........................................................................................7
Bumper and Kickplate......................................................................7
Cleaning...........................................................................................8
Shelves............................................................................................9
Loading the Case.............................................................................9
Light Switch......................................................................................9
Case Thermometer..........................................................................9
Service...........................................................................................10
Fan Removal..................................................................................11
Refrigeration..................................................................................11
Electrical........................................................................................12
Defrosting - Low Temp...................................................................14
Anti-Sweat Heaters - Low Temp ....................................................18
Anti-Sweat Heaters - Medium Temp..............................................18
Doors.............................................................................................18
ILLUSTRATIONS.................................................................................19
Case Label Information..................................................................19
Leveling..........................................................................................20
Moving Cases................................................................................26
RHZC / RHCC Caulking Instructions.............................................27
Required Sealing for NSF-Approved Installations.........................28
Joining Insulated Dividers - RHZC / RHCC to RHZC / RHCC.......29
Joining Insulated Dividers - RHZC / RHCC to RVLC / RVMC .......30
Attaching Kickplate Splice - RHZC / RHCC to RVLC / RVMC.......31
Field Mounted Trap........................................................................32
Under Case ReturnAir Flow..........................................................34
Penetration Sealing........................................................................35
P-trap Installation...........................................................................36
General..........................................................................................37
Refrigeration Line Sizing - Low Temp............................................38
Refrigeration Line Sizing - Medium Temp......................................40
Electric Defrost - Low Temp...........................................................41
Hot Gas Defrost - Low Temp..........................................................42
Single Point Connection - Low Temp.............................................43
Master/Satellite Wiring - Low Temp ...............................................44
Off Cycle Defrost or Satellite Wiring - Medium Temp.....................45
Single Point Connection or Master Wiring - Medium Temp ...........46
Hot Gas Defrost - Low Temp..........................................................47
Electric Defrost - Low/Medium Temp.............................................48

Zero Zone Warranty • 1
ZERO ZONE WARRANTY
Limited Warranty
Zero Zone, Inc. (Seller) hereby warrants that any products manufactured by it and sold are warranted to be free from defects in material and
workmanship, under normal use and service for its intended purpose, for a period of one (1) year from the date of original installation (not to
exceed 15 months from the date of factory shipment). Zero Zone ChillBrite®LED Lighting carries a 5-year parts warranty. Zero Zone CoolView®
Doors carry a 10-year glass pack parts warranty. The obligation under this warranty shall be limited to repairing or exchanging any part, or parts,
FOB Factory, which is proven to the satisfaction of the Zero Zone Service Department to be defective. Zero Zone reserves the right to inspect
the job site, installation, and reason for failure. This limited warranty does not cover labor, freight, or loss of food or product, including refrigerant
loss. This warranty does not apply to motors, switches, controls, lamps, driers, fuses, or other parts manufactured by others and purchased by
the Seller unless the manufacturer of these items warrants the same to the Seller, and then only to the extent of those manufacturer’s warranty
to the Seller.Any products sold on an “AS IS” basis shall not be covered by this warranty.
Extended Warranties
In addition to the standard limited warranty, for further consideration, the Seller will extend to the original purchaser prior to shipment, a limited
extended warranty on the compressor only, following expiration of the standard warranty. The Seller agrees to repair or exchange, at its option,
or provide reimbursement for such exchange as directed, less any credit allowed for return of the original compressor, of a compressor of
like or similar design and capacity, if it is shown to the satisfaction of Zero Zone that the compressor is inoperative due to defects in factory
workmanship or material under normal use and services as outlined by Zero Zone in its Installation & Operation Manuals and other instructions.
Length of Extended Warranty
Any compressor warranty may be extended for an additional four (4) years, but such extension must be purchased prior to shipment to be
effective.This warranty is only for the compressor and not for any other associated parts of the refrigeration system.
Product Not Manufactured by the Seller
The written warranty, if any, provided by the manufacturer of any part of the refrigeration unit sold by Seller to Buyer, but not manufactured by
Seller, is hereby assigned to the Buyer. However, Seller makes no representation or warranty regarding the existence, validity, or enforceability
of any such written warranty.
Limitation and Exclusion of Warranties
THE WARRANTIES SET FORTH HEREINARE EXCLUSIVEAND IN LIEU OFALL OTHER WARRANTIESAND REMEDIES WHATSOEVER,
INCLUDING, BUT NOTLIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITYAND/OR FITNESS FORAPARTICULAR PURPOSE.

2 • Introduction - Important User Information
INTRODUCTION
Important User Information
Copyright © 2019 Zero Zone, Inc.
All rights reserved. No part of the contents of this manual may be reproduced, copied, or transmitted in any form or by any means including
graphic, electronic, or mechanical methods or photocopying, recording, or information storage and retrieval systems without the written
permission of the publisher, unless it is for the purchaser’s personal use.
The information in this manual is subject to change without notice and does not represent a commitment on the part of Zero Zone. Zero Zone
does not assume any responsibility for any errors that may appear in this manual. In no event will Zero Zone be liable for technical or editorial
omissions made herein, nor for direct, indirect, special, incidental, or consequential damages resulting from the use or defect of this manual.
The information in this document is not intended to cover all possible conditions and situations that might occur. The end user must exercise
caution and common sense when installing, using, or maintaining Zero Zone products. If any questions or problems arise, call Zero Zone at
800-247-4496.
Any change to a Zero Zone product made during the installation, start-up, or at any other time must be submitted in writing to Zero Zone for
approval and be approved by Zero Zone in writing prior to commission. The product warranty is voided when any unapproved change is made
to a Zero Zone product.
Manufacturer
Zero Zone, Inc.
Display Case Division
110 N Oakridge Dr • North Prairie, WI 53153 • 800-247-4496 • www.zero-zone.com
Intended Use
Zero Zone products are intended to be installed and used as described in this manual and other related Zero Zone literature, specications,
drawings, and data.Always install Zero Zone products on a level surface.
The information contained in this manual pertains to Zero Zone Display Cases, which include the following:
Display Case Models
LOW TEMPERATURE DISPLAY CASES MEDIUM TEMPERATURE DISPLAY CASES
RHZC30 RHZC30T RHCC30 RHCC30T
RHZC30BB RHZC30TBB RHCC30BB RHCC30TBB
RHCC24
Zero Zone produces high quality refrigerated display cases using state-of-the-art components. The cases are built with the thickest insulation in
the industry and a high efciency evaporator coil.
Potential case features include:
Brushless D.C. electronic fan motors
Zero Zone ChillBrite®LED lighting
Zero Zone CoolView®doors with heated glass and rails on low temp cases
Zero Zone CoolView®no-energy doors on medium temp cases

Introduction - Display Case Models • 3
INTRODUCTION
These display cases were designed and tested using the following industry standards:
ASHRAE Standard 72-2014 — Method of Testing Commercial Refrigerators and Freezers (ANSIApproved)
AHRI 1200 — Performance Rating of Commercial Refrigerated Display Merchandisers and Storage Cabinets (ANSIApproved)
UL 471- Commercial Refrigerators and Freezers (ANSI Approved) (equipment certied by ETL)
NSF 7- Commercial Refrigerators and Freezers (ANSI Approved) (equipment certied by NSF)
DOE Compliant (all U.S. sales)
ASHRAE 72-2014 species the test conditions for the equipment. It includes the ambient conditions of 75°F dry bulb and 55% RH. It also
species the door opening requirements for the performance test. Doors are opened 6 times in 1 hour for 6 seconds. The door opening test
period is for 8 hours during one 24-hour performance test.As an example, a 5-door case will have 240 door openings during one 24-hour test.
Consult the factory if your store exceeds these test conditions.

4 • Installation & Operation
INSTALLATION & OpERATIONINSTALLATION & OpERATION
Delivery Inspection
These display cases were carefully factory-tested, inspected, and properly packed to ensure delivery in the best possible condition. The
equipment should be uncrated and checked for damage immediately upon delivery. DAMAGE MUST BE NOTED AT TIME OF DELIVERYAND
ALL CLAIMS FOR DAMAGES MUST BE FILED WITH THE TRANSPORTATION COMPANY - NOT WITH Zero Zone. The carrier will supply
necessary report and claim forms.
Packaging
Each case in a lineup is labeled to identify the lineup and joint. The label uses a number and letter designation. The number indicates the lineup.
The letter indicates the case joint. Case joints begin with the letterAat the left most joint in the lineup when looking at the front of the lineup.
The joint for two cases has the same number-letter designation. Back-to-Back cases have a unique designation. The left most joint in the lineup
when looking at the front of the case is labeled 1-A. The joint on the back of the case is 1-A1. See Figure 1 on page 19.
Insulated dividers are factory-installed to separate low and medium temperature cases. They are also used to join different case models.
Factory-installed plexiglass dividers separate refrigeration circuits.
The rst case in the lineup (with the right side labeled “A”) has a packet attached to the door handle that contains the manual, special
instructions for installing ordered options, and touch-up paint if the cases are custom painted. Every case in the lineup has a packet attached to
the door that contains the specic information for that case. The packing slip is taped to the right-hand door of each case.
Bumpers and kickplates are shipped on top of the case. Shelves for the case are tie-wrapped and blocked into the individual cases. Other
accessories like drain traps, drain pans, condensate evaporation pans, and hat channel rails are shipped in the case that require the parts.
Materials for joining cases include caulk, joining bolts, splices, and Case Joint Vertical Trim.These parts are supplied in cases that have a left-
side insulated divider or no left end. The parts are bagged and taped to the coil covers. The Case Joint Vertical Trim is tied to the shelves.
Location
These cases must not be installed in the direct rays of the sun or near a source of radiant heat.
Be certain that the oor under the installation is of sufcient strength to prevent sagging. Unlevel conditions will result in reduced performance.
Wall cases (cases set with a back to a wall) and cases set back-to-back, should be positioned to allow a minimum 3-4" space behind the back
of the unit(s). This will allow necessary air to circulate behind the display case(s). Higher humidity stores with minimal air circulation require a 4"
gap.
Recommended minimum 2" gap between cases on end-to-end installations.
Leveling
Cases must be installed perfectly level to allow efcient operation of the refrigeration coils and complete drainage of defrost water. Since a level
area is seldom available, the following steps are recommended to ensure a level installation.
1. Measure off and mark on oor the exact dimensions of the case lineup. See Figure 2Aon page 20. (Check blueprints.)
2. Snap a chalk line at the locations for the front and back positions of the bases.
3. Mark locations of all joints (front and back).
4. Using a laser or transit, nd the highest point along both base rail position lines. Using the high point as a reference, mark the difference
directly on the oor to each base, front and back. See Figure 2B on page 20.

Installation & Operation • 5
INSTALLATION & OpERATION
5. If you plan on using optional hat channel rails to raise the case height, place them under each pair of bases. The 3 and 4-door hat channel
rails will be angled slightly to support the front and rear bases. See Figure 4 on page 22 and See Figure 6I on page 25.
6. Place the required number of shims under each base or optional hat channel rails at each joint (front and back) to equal the highest point.
7. The RHZC30 and RHCC30, 2 through 5-door cases, have segmented bases mounted at the ends and under the center section of the
case. The RHZC30 and RHCC30 1-door and RHZC30BB and RHCC30BB have full bases that run front to back and are located at the
ends and under the center sections of the case.
8. Tape all shims in place. See Figure 2C on page 20. Ensure the correct orientation of shims under the base or channel. See Figure 5
on page 22.
9. Place additional support shims under all other bases or hat channel rails. See Figure 6 on page 23.
10. Use a carpenter’s level to check installation as you go.The case should be level from front to back and side to side. Install the case
at the highest point rst, if part of a lineup. Check the level on the face of the glass doors and sides of the mullions. Do not use the ceiling
to check level.
11. If you’ve purchased seismic restraints, specic instructions for attaching those restraints are included in your document package. These
instructions should be read and followed before the lineup is assembled.
Setting the Case
Position hat channel rails with tape up.
For 3 and 4-door cases, the center hat channel rail needs to be angled to rest on front and back base. Do not locate under drain hub. For 5-door
cases, there are 4 hat channel rails. See Figure 3 on page 21.
In most instances, cases will require leveling by using shims. Refer to the Leveling Section.
Moving Cases
The Back-to-Back (BB) cases are shipped with wood planks that allow the use of pipe rollers. These wood planks should be removed after the
case is moved to its nal location. See Figure 7 on page 26.
The RHZC, RHCC, and BB cases have steel protective support plates under the ends (not under insulated dividers). These are designed to
protect the end from Johnson Bar damage.
Use the following methods to move the cases:
MODEL FORK LIFT FROM
ENDS JOHNSON BAR FURNITURE DOLLY PIPE ROLLERS SAFE (CASE) JACKS
RHZC30    
RHZC30BB 
1RHZC30 *   
RHCC30    
RHCC30BB 
1RHCC30 *
* Fork lift from rear
Care should be taken when moving the cases. The doors should be secured so they cannot open while the case is moved.

6 • Installation & Operation
INSTALLATION & OpERATION
Only experienced, certied fork truck drivers should use fork trucks to move the cases. The case should only be lifted off the oor as high as
necessary for transport. The fork truck should be driven slowly to avoid any abrupt motions or bumps.
The following forklift dimensions must be maintained to avoid damaging the case when it is lifted:
2-DOOR CASES
Forks must extend from 26" to no more than 28" under the case.
3-DOOR CASES
Use 48" long forks!
Forks must extend from 39" to no more than 43" under the case.
4 & 5-DOOR CASES
Use 48" long forks!
Fork blades wider than 4" will not t in the bases.
Spacer blocks are factory-installed in the end bases of 4 and 5-door cases that use 4 1/2" bases. See Figure 8 on page 26. These blocks
limit the case's forward tilt while it is being lifted and must be used when lifting 4 or 5-door cases with 4 1/2" bases.
For low shipping height applications, Zero Zone has optional, expandable bases.As shipped, the base is 1 3/4" tall. It is attached with spacers
that allow the base to slide away from the bottom of the case to create a gap that allows the use of a 1 1/2" thick fork truck blade. See Figure 9
on page 26.
LineupAssembly
Zero Zone display cases have been engineered for continuous display. This means that any number of cases can be joined together to create a
display of a desired length. The bottom of the end panel is protected with a removable steel plate.
The cases will be ready for assembly after removal of the packaging material.
Case caulking instructions are shipped with every case, explaining the proper procedure for joining cases. See Figure 10 on page 27.
Instructions on joining a Highlight™case to a Crystal Merchandiser™case are detailed as well. See Figure 14 on page 30 and See Figure 15
on page 31.
FIELD-INSTALLED CAULK SEALANT APPLICATION NOTES:
Butyl sealant is used to join cases and silicone or NSF approved sealant is used for NSF compliance. Sealants should not contact one another
as this may affect adhesion or color of each.
Remove all shipping blocks applied to inside of base ends before joining cases.
Remove end protection plate located below end on outside of case.
FAILURE TO FOLLOWTHE INTENT OF CASE JOINING INSTRUCTIONS WITH SEALANTS WILLCAUSE FROST INSIDE THE CASE.
For NSF case installation compliance, the interior case seams need to be sealed using NSF approved caulk (not supplied). See Figure 11 on
page 28.

Installation & Operation • 7
INSTALLATION & OpERATION
After setting the rst case, the next case is slid into position and bolted to the rst case using four 3/8" bolts that are provided. Begin tightening
the bolts at the top rear, working down the back of the case and up the front, making sure that the front seams are ush. Do not attempt to pull
cases together using the joining bolts.
Alignment holes are located in the lower steel end frames. These are located 7" in from the joining holes.
Once the cases have been caulked and slid together, start the joining bolts, but do not tighten them. Begin tightening the bolts at the top rear,
working down the back of the case and up the front, making sure that the front seams are ush. Cases are not designed to be pulled together
using the joining bolts. Please note that when bolting the cases together, there is a welded nut in the rear center of the left mullion of the right-
hand case. Therefore, it is not necessary to remove the rear ductwork of the right-hand case. Place the case joint vertical trim over the vertical
raceway and screw into place.
Two different model cases or two different temperature cases are connected using an insulated divider. Typically the divider is factory-
assembled to one of the cases. Two styles of divider are provided. The rst style has a panel on each side with nut inserts in the panels. Each
side is bolted to the end frame. The second style divider uses a thru-bolt design. The divider is attached to one of the cases using short bolts.
When the case is installed, the short bolts are removed and long bolts are reinstalled to bolt both cases together. See Figure 13 on page 29.
Do not attempt to pull cases together using the joining bolts.
Drain Line
The drain is located at the center of the case in the oor pan. The drain can be reached by removing the center coil covers and then removing a
fan motor. The 1" PVC drain outlet is located at the center front of the case behind the kickplate.
Install the tee to the outlet pipe and a drain trap to the tee. Plug the open end of the tee using the clean-out plug supplied with the drain trap
kit. The drain line must be pitched away from the case.The tee, drain trap, and plug are supplied with the case. We supply a trap support
that is eldmounted to the case. See Figure 16 on page 32. The drain trap must be level. The drain trap should be primed with water after
installation. The drain line must be pitched away from the case enough to ensure proper drainage. Consult your local codes for minimum
requirements.
Bumper and Kickplate
AZero Zone bumper is standard on all case models and should be installed at the bottom front of the case. Various bumper styles are available.
See Figure 17 on page 33. The kickplate assembly is adjustable to compensate for uneven oors. The bumper end cap is factory-installed
on bumpers for cases with end panels that do not include Euro trim.
STEP 1: INSTALLING END KICKPLATE
The end kickplate attaches to the small black bracket attached to each side of the case with an end. The kickplate can be adjusted vertically to
match the height of the oor below it. See Figure 18 on page 33.
1. Attach a Tinnerman clip to the side bumper support.
2. Place the side kickplate against the Tinnerman clip on the side bracket.
3. Install the black 3/4" screw through the side kickplate and into the Tinnerman clip.Ascratch-awl or similar tool can be used to line up the
holes.
4. The front of the side kickplate is located behind the front kickplate and attached with screws to the front kickplate.
STEP 2: INSTALLING BUMPER AND FRONT KICKPLATE
The front kickplate and bumper attaches using 1 1/2" screws attached to brackets located on the front of the case. The kickplate can be
adjusted up and down to t the height of the oor below it.

8 • Installation & Operation
INSTALLATION & OpERATION
1. Starting from the left end of the lineup, attach a Tinnerman clip to each bumper support bracket. Locate them over the hole for the bumper.
2. Attach the kickplate splice to the right side of the kickplate using the 3/4" screw in the lower hole.
3. Lean the kickplate against the bumper support bracket.
4. Hang the bumper on the case. The kickplate should be located behind the bumper assembly.
5. Install the black 1 1/2" screw through the bumper, kickplate, kickplate splice, and into the Tinnerman clip.Ascratch-awl or similar tool can
be used to line up the holes.
6. Follow these steps to install the next bumper in the lineup.Abumper splice (provided) should be installed between the two cases. Center
the splice and adjust the height so the decorative tape (if applicable) lines up. Using self-tapping screws (provided), attach the upper
portion of the splice using the predrilled holes in the splice. Then with two more screws, attach the lower half.
UNDER CASE RETURNAIR FLOW ASSEMBLY INSTRUCTIONS
To assemble the bumper for under case return air ow (if requested), a spacer (provided) must be inserted between the bumper and kickplate.
See Figure 19 on page 34. The spacer is held in place with the standard black assembly screw used to attach the bumper. One 3/8" spacer
is required at each screw location (2 spacers on a 2-door, 3 spacers on a 3-door, etc.).
1. To ease installation, hook the bumper to the case and position the kickplate. Then pull the bottom edge of the bumper forward, hold the
spacer in place, and then insert the assembly screw through the bumper, spacer, kickplate, bumper bracket, and into theTinnerman clip.
2. With the spacers in place, air will be allowed to ow between the bumper and kickplate and then underneath the case. The target airow
rate under the case design is 50 cfm/door.
Note:An optional louvered kickplate is available. (Provides 150 cfm/door.)
Cleaning
The case and doors are cleaned prior to shipping. However, the case should be thoroughly cleaned before start-up and routinely thereafter to
maintain a clean appearance. Use mild detergent and warm water (never an abrasive cleaner) to wipe out the inside of the case. Wash down all
glass doors with glass cleaner. Do not wash down the fan motors. Do not use any products containing silicon on anti-fog glass coatings. Clean
interior glass reduces fogging and increases visibility. The case will remain bright and sparkling with just a few minutes of cleaning each week.
Internal components can be cleaned after removal of access panels. The case drain should be regularly cleared of debris and price tags.
Coils may be cleaned with a garden hose or pails of water. Cases that use pump, drain pans and condensate evaporators should be cleaned
with a minimum amount of water. The drain should be blocked and the water removed with a shop vacuum.
Do not use high-pressure water or steam to clean the interior.
UNDER CASE FLOOR CLEANING (NSF)
The oor underneath your Zero Zone display case can be cleaned by following a few simple steps:
1. Remove the fasteners that hold the bottom kick plate to the display case. The fasteners are accessed from the front of the unit.
2. With the kick plates removed, remove paper and other debris (typically price tags or receipts) from the oor.
3. Vacuum under the case to remove any dust build-up that may be present.
4. Using an approved cleaner and warm water, mop underneath the unit.
5. When nished mopping, squeegee any remaining water underneath the unit to the oor drains to speed the drying process. Replace the
kick plates when the oor has dried.

Installation & Operation • 9
INSTALLATION & OpERATION
GLASS SURFACES
Cleaning interior glass reduces fogging and increases visibility. Wipe down glass or plexiglass mirrors or ends with a glass cleaner. Do not use
any products containing silicone.
Shelf Location
The shelves are adjustable in 1" increments on cantilever shelf cases and may be located in any position for best display advantage.
Be sure brackets are completely seated.
Wire shelf brackets are stamped with “R” for Right and “L” for left to aid installation.
Shelves
Zero Zone manufactures many different styles of shelves, baskets, and product stops. The fully assembled shelves are installed in cases prior
to shipping. The bottom wire racks and baskets are placed on the shelves for shipping. Solid shelves have three parts: a solid center section
and two snap-in brackets. Some of the baskets may be reversed and used as a typical shelf.
Solid shelves can be disassembled for cleaning.Ascrewdriver can be used to spread the snap open to remove the brackets from the center
section.
Loading the Case
The case may be loaded with product after it has been operated for at least 24 hours with correct case temperature and proper control
operation. While loading the shelves, leave a minimum of 1" air space between the top of the product and the shelf above it so the customer
can remove the product. The air space allows an air curtain on top of the product. Product should not extend beyond the front of the shelves or
block the return air grill. The shelf loads are as follows:
ITEM SHELF
DESCRIPTION MAXIMUM LOAD PER SHELF
1 22" and 24" deep 250 lbs.
2 4-Position Brackets
At 0° 250 lbs.
At 5° 250 lbs.
At 10° 150 lbs.
At 15° 100 lbs.
3 Heavy Duty 500 lbs.
Heavy duty shelves are available and are labeled as such.
Light Switch
The light switch is located on the ceiling on the right-hand side of the display case.
Case Thermometer
The cases are shipped with 2 thermometers. The rst thermometer is factory-mounted in the discharge air stream. The second thermometer,
required by NSF, is shipped loose and should be installed in the warmest product location. Specic instructions are included.

10 • Installation & Operation
INSTALLATION & OpERATION
Service
UNDER CASEACCESS
The bumper and kickplate must be removed to gain access to the drain clean out and electrical connections. Disassemble the bumper and
kickplate by removing the 2 or 3 metal screws located in the kick rail. The bumper assembly can be lifted up and removed from the case. The
kickplate can be removed, exposing the drain and electric enclosure cover. An optional top electrical box is available for easier installation and
accessibility.
EVAPORATOR
The evaporator coil, located at the rear bottom of the case, is factory-assembled with distributor, expansion valve, and other refrigeration
components. To inspect the coil, remove the center or left of center coil cover.A small inspection window is located at the rear of the case.To
inspect the entire coil, remove the remaining coil covers and raise the metal evaporator cover.
EXPANSION VALVE
Unless otherwise specied, a superheat, externally-adjustable, equalized thermostatic expansion valve with pressure limiting charge (low temp
only) is mounted to the evaporator coil. The valve is not preset.Adjust the superheat setting for maximum coil effectiveness. Typical superheat
settings are between 6°F and 10°F. Close coupled systems should use the higher superheat setting to minimize the chance of liquid ood back.
To adjust the expansion valve, remove the right end coil cover. Remove the cap from the bottom of the valve. When looking at the valve stem
end, turn the valve stem counterclockwise to decrease superheat. Turn the valve stem clockwise to increase superheat. Measure the suction
line temperature at the expansion valve sensing bulb and compare it to the suction temperature corresponding to the saturated pressure. Make
sure that line pressure drop is taken into account.
Turn the valve stem only 1/4 turn at a time and allow sufcient time (20 to 30 minutes) for the valve to settle before making any further
adjustments. Replace the valve stem cap after the valve superheat has been adjusted. BE CERTAIN THE VALVE STEM CAP IS WIPED DRY
FIRST.
! CAUTION! DISCONNECT POWERTOTHE CASE BEFORE SERVICING ELECTRICALCOMPONENTS TOAVOID PERSONAL
INJURYAND DAMAGE TO THE UNIT.
EVAPORATOR FANS
Air is circulated throughout the case with 115 volt low temperature fan motors. These motors must be operating at all times, except during
defrost in low temp cases. Fan motors should be replaced with motors having the same characteristics including type, physical size, lubricant
temperature range, wattage, and RPM. Fan blades should be replaced with factory original equipment part.
CONDENSATE EVAPORATION SYSTEM
Zero Zone remote cases can be equipped with an automatic condensate evaporation system. The system uses a pump and drain pan located
behind the kickplate and a condensate evaporator pan mounted on the top of the case.
Condensate water and any liquid spilled in the case drains out into the drain pan. The pump is equipped with a oat that turns the pump on
when there is a sufcient liquid level. Liquid is pumped through a plastic hose through a check valve and into the condensate evaporation
pan. The evaporation pan is equipped with a heater and a oat switch to turn on when the heater is submerged in liquid. When the heater is
energized, the pan will be extremely hot and should not be touched. The pump and condensate pan should be cleaned regularly.Any spilled
product should be cleaned to prevent odors.

Installation & Operation • 11
INSTALLATION & OpERATION
AIR CURTAIN VELOCITY
Air curtain velocity is affected by stocking levels, coil frost loads, temperature, and fan condition.Air velocity should be measured at the back
edge of the discharge air honeycomb, at the center of the middle door in the case (other doors have slightly lower velocity).Atypical low temp
velocity reading is 400 to 500 feet per minute in a fully-packed low temp case, after the case has defrosted and pulled down to operating
temperature. Air curtain velocity in a partially-packed display case is signicantly lower because more air exits the back wall duct holes. In fully
stocked medium temp cases, the velocity should be 300 to 400 feet per minute after the case has defrosted and pulled down to temperature.
Note: Indicated velocity can vary considerably from one velometer to another.
FAN REMOVAL
1. Turn off power to fans. Remove coil cover.
2. Unplug fan from fan power supply plug located on the front face of the fan housing.
3. Remove the fan blade nut and fan blade.
4. Remove the two mounting bolts and remove the fan assembly from the fan housing.
5. Remove the three fan motor mounting screws from the back of the fan motor.
6. Reverse steps 1 - 5 to install.
LED POWER SUPPLIESAND DRIVERS
LED Drivers for the Highlight™cases are located behind the kickplate in the electrical enclosure.
Refrigeration
Unless otherwise specied, the liquid and suction connections are made inside the case under the removeable evaporator fan/coil return air
grill bottom. Refrigerant piping may enter the case through the front left bottom, the left rear bottom, or the left rear top of case. The copper
pipe should not touch or rub on the edges of the sheet metal.After connections have been made, the refrigeration access hole in the case must
be sealed completely with an aerosol-dispensed urethane insulation or equivalent (e.g. GREAT STUFFf™). Penetrations made in sheet metal
bafes should also be sealed. See Figure 20 on page 35.
REFRIGERANT PIPING
Correct refrigeration line sizing and installation is essential for proper system operation. See Figure 24 on page 38, See Figure 25 on page
39,and See Figure 26 on page 40 for Highlight™cases. Contact the factory for line sizing for the Highlight™cases.AP-trap must be
installed at the bottom of all vertical suction risers. See Figure 21 on page 36. Various risers are available as a factory-installed option. The
compressor should be installed as close as possible to the cases to reduce pressure drop. Install a shallow trap at the bottom of the riser.
When two or more case sections are connected to one compressor, the main liquid and suction line for the group should be run through the
cases and be brought out through the refrigeration outlet of one case only. The factory recommends one riser per circuit/system for hot gas
defrost when using top back refrigeration exit. Circuit risers are available as a factory-installed option. On 30" wide door cases with suction lines
over 1 3/8" diameter, a P-trap made with 45° elbows is required. A piping chase in front of the fan shroud allows the refrigerant lines to be run
through the right or left end frame.
Piping should not be placed near the electric defrost heaters. The defrost heaters on the 30" door cases will grow one inch to the left of the coil
when they reach operating temperature.

12 • Installation & Operation
INSTALLATION & OpERATION
The best location for the liquid line drier is inside the case compartment. However, it may be installed near the compressor for easy
maintenance. Install moisture indicating sight glass at the outlet end of the drier.
Alow pressure or temperature control can be used to control case temperature. The control should be selected with adequate contact capacity
for the switching load. In rack systems, an evaporator pressure-regulating valve may be used to control the evaporating temperature.
The settings are approximate due to variations in gauge accuracy, differences in compressor efciency, line pressure drop, and superheat
settings. See Figure 22 on page 37. Before making adjustments for store or stocking conditions, make sure the superheat is set.
Close coupled systems typically run at the higher end of this range to avoid ood back.
TEMPERATURE CONTROL ADJUSTMENT
When factory-installed, the temperature control is located toward the right end of the case in the electrical enclosure. The sensing bulb is
located under the coil cover inside the fan shroud. It can be wired in series with the low-pressure (L.P.) control. It can also be used in a pump
down system by wiring it in series with the liquid line solenoid valve. See Figure 23 on page 37 for a thermostat.
Discharge air temperature probes for electronic case controllers may be installed in many different customer-specied locations including, but
not limited to, honeycomb, ceiling pocket cover, rear wall, and return air.
LEAK-CHECK/EVACUATION/CHARGING
After all of the refrigeration piping and system components have been assembled, the entire system must be pressurized and checked for leaks.
When the system is leak free, evacuate with a deep vacuum pump. Triple evacuation to a maximum of 500 microns and nitrogen sweep is
recommended.After the system has been thoroughly evacuated of all moisture and noncondensable gas, charge the system with the proper
refrigerant, using “hi-side/low-side” charging techniques.
Do not exceed ULlow side pressure rating when pressure testing Zero Zone cases.
Electrical
! CAUTION! DISCONNECT POWERTOTHE CASE BEFORE SERVICING ELECTRICALCOMPONENTS TOAVOID PERSONAL
INJURYAND DAMAGE TO THE UNIT.
For the typical wiring diagram for a low temperature case equipped with electric defrost See Figure 27 on page 41. For the typical wiring
diagram for a low temperature case equipped with hot gas defrost See Figure 28 on page 42. For the typical wiring diagram for a medium
temperature case See Figure 31 on page 45. Each case is provided with a wiring diagram located in the electrical enclosure that shows the
exact wiring of the case.
There are many control options available for multiple case defrost systems. Wiring diagrams and instructions can be obtained by contacting
Zero Zone’s Service Department.
External wiring should be sized according to the amperage rating indicated on the serial plate. The serial plate is located on the ceiling inside
the left-hand door. Typical electrical values for each of these cases are shown on specication sheets in the bag attached to the case or are
available at www.zero-zone.com.All internal wiring has been done at the factory. Cases with standard wiring have their control wires terminated
in the electrical enclosure located behind the kick rail at the right end of the case. A terminal block has been used to simplify eld connections.
An electrical box is mounted on the top of the unit for cases equipped with the optional top mount electrical connections.
All wiring must comply with the National Electrical Code and all local codes.After installation of the equipment, correct operation of the electrical
circuits and controls and defrost operation and termination should be veried. All operating voltages and amperages should be measured and
recorded.

Installation & Operation • 13
INSTALLATION & OpERATION
OPTIONAL ELECTRICAL WIRING
Single Point Connection (Low Temp)
The “single point” connection system is designed to reduce the time required to install and wire one display case with one condensing unit. See
Figure 29 on page 43.
All of the display case controls, including the disconnect switch and the electronic case controls are installed behind the kickplate in the
electrical enclosure and prewired. The liquid line solenoid valve is installed in the liquid line and wired.
The power to operate the display case is connected at the case disconnect switch. The power to operate the condensing unit is connected in
the condensing unit control panel. There are no interconnecting wires between the condensing unit and display case.
The controls operate the system as a pump down defrost. When the display case begins defrost, the liquid line solenoid valve, fans, and
anti-sweat heaters are de-energized. The defrost heaters are energized.The compressor continues to run and pumps down the coil. The
compressor cycles off on its low-pressure control. If there is any residual liquid left in the coil, the suction line pressure will rise and the
compressor may turn on and pump down the coil.
The liquid line solenoid is energized at the end of the defrost cycle and the defrost heaters are de-energized. The suction line pressure rises
and the compressor starts. When the low temperature evaporator reaches operating temperature, the fans and anti-condensate door heaters
are energized.
Single Point Connection (Medium Temp)
The “single point” connection system is designed to reduce the time required to install and wire one display case with one condensing unit. For
a typical diagram for this system See Figure 32 on page 46.
All of the display case controls, including the disconnect switch and electronic case controls, are installed behind the kickplate in the electrical
enclosure and prewired. The liquid line solenoid valve is installed in the liquid line and wired.
The power to operate the display case is connected at the case disconnect switch. The power to operate the condensing unit is connected in
the condensing unit control panel. There are no interconnecting wires between the condensing unit and display case.
The controls operate the system as a pump down defrost. When the display case begins defrost, the liquid line solenoid valve is de-energized.
The fans and anti-sweat heaters remain energized during defrost. The compressor continues to run and pumps down the coil. The compressor
cycles off on its low-pressure control. If there is any residual liquid left in the coil, the suction line pressure will rise and the compressor may turn
on and pump down the coil.
The liquid line solenoid is energized at the end of the defrost cycle. The suction line pressure rises and the compressor starts.
Master Satellite Connection (Low Temp)
The “master satellite” connection system allows one condensing unit to be connected to multiple cases. For a typical diagram for this system
See Figure 30 on page 44.
All of the display case controls, including the disconnect switch, time clock, temperature control, and defrost temperature control, are installed
behind the kickplate in the electrical enclosure and prewired. The liquid line solenoid is prewired but is not installed in the liquid line.
The power to operate each display case is connected at each case’s disconnect switch. The power to operate condensing unit is connected
at the condensing unit. There are no interconnecting wires between the condensing unit and display case. There are interconnecting wires
that need to be connected between the cases. The liquid line solenoid valve needs to be installed in the common liquid line before the liquid is
distributed to the cases.
The controls operate the system as a pump down defrost. When the display case begins defrost, the liquid line solenoid valve, fans, and anti-
sweat heaters are de-energized. The defrost heaters are energized.The compressor continues to run and pumps down the coil.

14 • Installation & Operation
INSTALLATION & OpERATION
The master case contains the time clock. Interconnecting case wiring allows the master case to control the satellite cases. When defrost is
initiated in the master case, it sends an electrical signal to each case to energize the defrost relay and initiate a defrost in all of the satellite
cases.Asecond set of interconnecting wires is connected in series between each of the cases. Each case defrost heater is de-energized when
the coil reaches the defrost termination temperature.An additional signal is relayed to the next case indicating that the termination temperature
has been reached. When all of the cases have reached termination temperature, the defrost termination circuit is complete and the defrost is
terminated.
The liquid line solenoid is energized at the end of the defrost cycle and the defrost heaters are de-energized. The suction line pressure rises
and the compressor starts. When the evaporator reaches operating temperature, the delay thermostat (Klixon) will close, energizing the fans
and anti-sweat door heaters.
Note: When using a Carel controller, the system will still function as a pump down system, but the Carel defrost function controls the defrost
termination of each case independently and requires a defrost sensor coming from each satellite case to the master case. Contact the Zero
Zone Service Department for specic operating characteristics.
Master Satellite Connection (Medium Temp)
The “master satellite” connection system allows one condensing unit to be connected to multiple cases. See Figure 30 on page 44 and See
Figure 31 on page 45.
All of the display case controls, including the disconnect switch, time clock, and temperature control, are installed behind the kickplate and
prewired. The liquid line solenoid is prewired but is not installed in the liquid line.
The power to operate each display case is connected at each case’s disconnect switch. The power to operate the condensing unit is connected
at the condensing unit. There are no interconnecting wires between the condensing unit and display case. There are interconnecting wires
that need to be connected between the cases. The liquid line solenoid valve needs to be installed in the common liquid line before the liquid is
distributed to the cases.
The controls operate the system as a pump down defrost. When the display case begins defrost, the liquid line solenoid valve is de-energized.
The compressor continues to run and pumps down the coil.
The master case contains the time clock. Interconnecting case wiring allows the master case to control the satellite cases. When defrost
is initiated in the master case, it sends an electrical signal to each case to initiate a defrost in all of the satellite cases.Asecond set of
interconnecting wires is connected in series between each of the cases.
The liquid line solenoid is energized at the end of the defrost cycle. The suction line pressure rises and the compressor starts.
Defrosting - Low Temp
GENERAL
Periodic defrosting to keep the coil free of frost is accomplished automatically by a time clock used in conjunction with an electric or hot gas
defrost method.
For best results, temperature termination of defrost is strongly recommended on Zero Zone cases.
DEFROST SETTINGSAND CONTROLS
Electric Defrost
Frequency: One electric defrost per day is recommended.
Time of day: Nighttime defrosting is preferred to avoid periods of shopping or stocking.

Installation & Operation • 15
INSTALLATION & OpERATION
Drip Time: Electric defrost does not require any drip time. Tha fans should not operate until the coil temperature is below freezing. The Zero
Zone standard case includes a fan delay thermostat that prevents the fans from operating until the coil is below freezing. Cases utilizing
electronic controls may utilize a coil temperature sensor to control fan operation instead of a fan delay thermostat.
Electric Defrost Fail-safe Times:
ICE CREAM FROZEN FOOD
RHZC30 1/day at 55 mins 1/day at 55 mins
RHZC30T 1/day at 55 mins 1/day at 55 mins
AtASHRAE test conditions and 208 volt defrost heater operation, the typical observed RHZC30 defrost durations are 55 minutes for ice cream
and 55 minutes for frozen food.At the same conditions, the typical observed RHZC30T defrost durations are 55 minutes for ice cream and 55
minutes for frozen food.
Preferred Termination: For optimal performance, Zero Zone recommends a temperature-terminated defrost, using a defrost termination
thermostat or probe sensing the coil temperature.
The RHZC30 and RHZC30T door case has the probe located in the center/bottom of the coil.
An adjustable defrost termination thermostat is an available option from Zero Zone. If the case is so equipped, the defrost termination
temperature is 50°F. Contractor should verify the 50°F setting.
Temperature termination based on coil temperature allows the length of defrost to vary depending on how much frost is on the coil and the
defrost heater voltage. Coil frost is a function of shopping patterns, stocking habits, general door maintenance, and ambient temperature and
humidity. More frost requires a longer defrost.Alower defrost heater voltage extends the defrost period.
Zero Zone electric defrost freezers are delivered with the defrost thermostat open-on-rise contacts wired in series with the defrost heaters.
Unless the installer rewires the defrost thermostat, the defrost heater is de-energized when defrosting is complete.
Zero Zone RHZC30 and RHZC30T door electric defrost freezers are also equipped with a high-limit, snap-disc thermostat that de-energizes the
defrost heater if the coil temperature exceeds 85°F to provide a secondary safety termination.
Hot Gas Defrost
Frequency: One hot gas defrost per day is recommended.
Time of day: Nighttime defrosting is preferred to avoid periods of shopping or stocking.
Drip time: Hot gas defrost requires a 5 minute drip time.
Hot Gas Defrost Fail-safe Times:
ICE CREAM FROZEN FOOD
RHZC30 / RHZC30T
Hot Gas
1/day at 30 mins
5 min drip
1/day at 30 mins
5 min drip
RHZC30 / RHZC30T
Reduced Temp Gas
1/day at 40 mins
5 min drip
1/day at 40 mins
5 min drip
Preferred Termination: For optimal performance, Zero Zone recommends a temperature-terminated defrost, using a defrost termination
thermostat or probe attached to the dump line.
At ASHRAE test conditions, termination ranges from 12-22 minutes. Measure dump line temperature, and time how long it takes to reach 65°F.
Add 5 minutes for time termination setting plus drip time.

16 • Installation & Operation
INSTALLATION & OpERATION
An adjustable defrost termination thermostat is an available option from Zero Zone. If the case is so equipped, the defrost termination
temperature is 65°F at the dump line. Contractor should verify the 65°F setting.
Electric Defrost Operation
The compressor stops when the defrost is initiated in a non-pump-down system. On pump-down systems, the liquid line solenoid will be de-
energized when the defrost is initiated. The clock will energize the 208/230 volt defrost heater, and energize the normally closed 208/230 volt
contactor or relay. This de-energizes the 115-volt fans, lights, and anti-sweat heaters. If you don’t have a light circuit limit thermostat, the lights
will not de-energize.
After the defrost period, the compressor will operate. When the coil temperature reaches +5°F, the fan thermostat (Klixon) will close, starting the
fans. See Figure 34 on page 48.
Gas Defrost Operation
Several types of gas defrost methods (using time-actuated, time-terminated, or temperature-terminated defrost timers) can be used to defrost
the evaporator.
The refrigeration system designer and installer are responsible for correct line sizing for effective gas defrost and liquid return from the freezers.
Sizing and component selection depend on the type of defrost, size, and location of high side refrigeration system.
Zero Zone freezers equipped for gas defrost consist of a side port distributor and a TXV check valve for coil defrost, and a suction line check
valve to bypass hot gas to the serpentine coil. The serpentine coil is attached to the bottom of the pan to ensure pan and drain defrost.
The timer starts the gas defrost cycle by energizing a solenoid, reversing valve, or directional valve. The gas is injected from the source into
the suction line of the evaporator to be defrosted. The gas ows into the serpentine coil attached to the oor of the case and then into the
evaporator. Condensed liquid leaves the evaporator through the side port distributor, through a check valve into the liquid line. See Figure 33
on page 47.
General Notes
The refrigeration technician should recheck coil condition after one week of retail operations to be certain that the frequency and duration
of defrost is adequate for the particular store and conditions. For example, if defrost voltage is below 200 volts, additional fail-safe time
may be required.
When using time-terminated defrost, defrost termination thermostat should be wired in series with the defrost heater.
Defrost termination thermostats may be wired in series for multiple evaporator installations.
Defrost termination thermostats may be used as a digital input for electronic controllers.
Limit Thermostat
The Zero Zone standard case includes a factory set limit thermostat (Klixon) attached to the return bend of the coil on the right end of the
freezer to regulate the operation of the evaporator fans. If selected by the customer, the lights may be controlled by a second limit thermostat.
Cases utilizing electronic controls may utilize a coil temperature sensor to control operation of the fans and lights instead of a limit thermostat.
IMPORTANT! OPERATION OF THE LIMIT THERMOSTATS CAUSES THE EVAPORATOR FANS TO REMAIN OFF UNTILTHE
COMPRESSOR IS OPERATING AND THE COIL TEMPERATURE IS BROUGHT BELOW THE THERMOSTAT CUT-IN SETTING (+5°F ).
SUPERHEAT MUSTBE SET CORRECTLY BY THE INSTALLING CONTRACTOR FOR PROPER THERMOSTAT OPERATION.
When the freezer rst operates, the fans and lights may cycle off and on a few times until coil temperature is below +5°F. The superheat must
be set for proper operation.
Electric defrost models have a high limit thermostat installed on the coil return bend, wired in series with the defrost heaters. This thermostat
opens when the temperature reaches 85°F.