Munters DRYCOOL RENTAL HCUb Series User manual

HCUB60304-HMXC
Rev 00
Reviewed __________
Date ______________
Contacts:
PT1
EC
Munters Service / Start-up Scheduling
888-349-4335
Munters Corporation
Commercial Dehumidification Division
16900 Jordan
Selma, TX 78154
[phone]
Desiccant Dehumidification Equipment
MANUAL
HCUb RENTAL
Model Number

Section 1 Operating and Maintenance
a) Operating and Maintenance Instructions OM0008-09
Section 2 Technical Data
a) Flow Diagram 2-1
b) Equipment Data 2-2
c) DX Coil Performance 2-3
d) Refrigeration Flow Diagram 7650-61 - 7650-62
e) General Arrangement Drawing HCUb6000 S71127-004
g) Operations Guide 2-4
h) Touch Screen Navigation 2-5
Section 3 Wiring
a) Wiring Diagram HCUb6000, 460V 5800-67
Section 4 Blowers
Section 5 Spares
a) Spare Parts List HCUb6000 5-1
OPERATING AND MAINTENANCE MANUAL
MODEL: DRYCOOL RENTAL HCUb SERIES
a) Supply Blower Curve – HCUb6000
b) Reactivation Blower Curve – HCUb6000

Section 1

INSTALLATION,
OPERATION &
MAINTENANCE
Warranty Safety Installation Operation Maintenance
DryCool HCUb
Rental Unit
Munters Technical Service Department [phone]
August 2013
Munters HCUb
Rental Plus
May 2017

Page 1 of 79
OM0008-09 HCUb Rental Plus
Table of Contents
1. Introduction ................................................................................................................................................2
1.1. Equipment Warranty.............................................................................................................................................2
1.2. Desiccant Dehumidifier Operating Principle..........................................................................................................5
1.3. Cooling Operating Principle..................................................................................................................................7
1.4. Filter Principle.......................................................................................................................................................7
2. Safety ..........................................................................................................................................................8
3. Installation..................................................................................................................................................9
3.1. Pre-Installation Requirements...............................................................................................................................9
3.2. Pre Checks and Inspection before Installation ......................................................................................................9
3.3. Positioning the Unit............................................................................................................................................. 10
3.4. Installation Requirement Checklist...................................................................................................................... 10
3.5. Connecting Air Supply Duct................................................................................................................................ 12
3.6. Connecting Condensation Drain.........................................................................................................................13
3.7. Connecting Electrical Service ............................................................................................................................. 13
4. Operating Instructions.............................................................................................................................14
4.1. Controls.............................................................................................................................................................. 14
4.2. Setting Up Control System..................................................................................................................................14
4.3. Starting the Unit..................................................................................................................................................14
4.4. Modes of Operation............................................................................................................................................ 14
4.5. Using Microprocessor.........................................................................................................................................17
5. Maintenance .............................................................................................................................................18
5.1. Overview ............................................................................................................................................................18
5.2. Quick Check....................................................................................................................................................... 18
5.3. Recommended Maintenance Schedule...............................................................................................................18
5.4. Inspecting Ductwork ........................................................................................................................................... 19
5.5. Replacing Air Filters and Cleaning Reactivation Coil...........................................................................................20
5.6. Inspecting Seals.................................................................................................................................................20
5.7. Inspecting Fans..................................................................................................................................................20
5.8. Inspecting Wheel Drive Motor and Belt............................................................................................................... 23
5.9. Inspecting Roller Wheels....................................................................................................................................23
5.10. Removing and Replacing Desiccant Wheel, Drive Belt and Seals....................................................................... 23
5.11. Inspecting Desiccant Wheel................................................................................................................................ 24
5.12. Cleaning Desiccant Wheel.................................................................................................................................. 24
5.13. Electronic Controls..............................................................................................................................................25
5.14. Inspecting Drain Pan and Drain..........................................................................................................................27
6. Troubleshooting.......................................................................................................................................28
6.1. Troubleshooting.................................................................................................................................................. 28
7. Appendix A: VFD Parameter Settings ....................................................................................................30
7.1. To Program J1000 and V1000 drives.................................................................................................................. 30
8. Appendix B: Sequence of Operation......................................................................................................33
8.1. Inputs ................................................................................................................................................................. 33
8.2. Outputs...............................................................................................................................................................33
8.3. Alarms................................................................................................................................................................34
9. Appendix C: Using VFD...........................................................................................................................36

1.Introduction
This manual includes installation, operation, and troubleshooting instructions for the DryCool HCUb-Plus Air
Cooled model. The goal of the manual is to provide the necessary information for the user to understand the
unit’s construction and function, and to serve as a guide during installation, operation, maintenance and basic
fault finding that generally can be carried out before contacting Munters Technical Support. The contents of this
manual include suggested best working practices and procedures.
The HCUb-Plus is designed to provide an economical way to bring makeup or recirculated air into the space
and control space temperature and humidity. The HCUb-Plus uses a cooling coil to cool and dehumidify the air.
The air is saturated with moisture as it leaves the cooling coil. The air then passes through a desiccant wheel
converting the latent heat (moisture) into sensible heat. This raises the air temperature to a room-neutral
temperature condition and at the same time lowers the dew point. This prevents overcooling the space at off-
design conditions. The desiccant wheel is reactivated by recycling waste heat from the condenser coil.
The HCUb-Plus has two compressors. They are two independently circuited refrigeration systems. The
condenser rejected heat is used for reactivation. Air is drawn through coils and then through desiccant wheel by
the reactivation fan. The reactivation fan is modulated by a VFD to maintain a constant discharge pressure
during dehumidification. The remaining rejected heat is handled by the conventional condenser fans also
controlled by VFD.
The HCUb-Plus can be controlled directly by a thermostat/de-humidistat or manual switches. These can be used
to give signals to turn on the supply fan, dehumidification and stages of cooling. The microprocessor monitors
and protects the HCUb-Plus internal functions and protections.
The HCUb-Plus can provide years of trouble-free service if you follow the recommendations listed in this
manual. We strongly recommended that you read this entire manual. The manual describes how to get the best
performance and service from your unit.
For questions concerning this manual, or concerning the dehumidifier, call the Munters Technical Service
Department at [phone] to speak with one of the Service Operation Technicians.
1.1. Equipment Warranty
WARRANTY FOR MUNTERS DEHUMIDIFICATION EQUIPMENT, SYSTEMS AND PARTS
Munters warrants that the Products (other than services and labor) shall be free from defects in workmanship
and materials for the lesser of (i) fifteen (15) months from the date of shipment of the Product by Munters; or

(ii) twelve (12) months from the date such Product become operational (collectively, the “Warranty”). For
purposes of standard terms and conditions of sale, including for the purpose of defining and describing
Purchaser’s remedy as provided below in this section, the term “Products” shall not include related services or
labor. Any extended warranties or warranties for services or labor shall be subject to Munters’ “Additional
Terms and Conditions – Service Plans,” which shall be provided by Munters to Purchaser if applicable.
The Warranty applies only to Products that are properly installed, maintained and operated under normal
conditions with competent supervision in accordance with the instruction manual, good maintenance practice
and Munters recommendations, if any, made by Munters in writing. Without limiting the foregoing, the
Warranty shall be void, and Munters shall have no liability for, in the case of any Products that: (a) have been
disassembled, repaired or tampered with in any way, except when such work has been done with Munters’ prior
written approval, (b) have been damaged by use or operation in excess of any maximum pressures, temperatures
or rated capacities as specified by Munters in writing, (c) have been damaged by corrosion, or have degradation
in performance as a result of dirt, dust, or other foreign material, or (d) are considered consumable.
Munters’ obligation, and Purchaser’s sole and exclusive remedy, under the Warranty is limited to repair or
replacement at Munters’ facility, at Munters’ option, of any Products (or parts thereof) determined to be
defective in workmanship or material during the applicable warranty period. The Warranty is a parts only
warranty, and except as may be provided in “Additional Terms and Conditions – Service Plans,” if these
Additional Terms are applicable, the Purchaser’s remedy under the Warranty does not include services or labor.
The warranty period shall not be extended by the performance of warranty repairs or replacements.
The Warranty shall be voided if payment is not made in accordance with the terms as set forth by Munters and
conditions of sale.
THIS WARRANTY IS EXPRESSLY IN LIEU OF ALL OTHER WARRANTIES EXPRESSED OR
IMPLIED, AT LAW OR IN EQUITY, WITH RESPECT TO THE PRODUCTS, ANY RELATED SERVICES
OR LABOR OR THEIR CHARACTERISTICS, QUALITY OR PERFORMANCE, INCLUDING WITHOUT
LIMITATION ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR
PURPOSE, OR NON-INFRINGEMENT OF ANY INTELLECTUAL PROPERTY RIGHTS OF THIRD
PARTIES, AND ANY AND ALL SUCH WARRANTIES AND REPRESENTATIONS ARE HEREBY
DISCLAIMED. No agent, representative, or dealer, or any other person or entity, is authorized to give on
Munters’ behalf any representation or warranty as to Product(s) or to assume for Munters any liability pertinent
to Product(s) under any circumstances .
DISCLAIMER OF DAMAGES AND LIMITATION OF LIABILITY
IN NO EVENT SHALL MUNTERS BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL OR
CONSEQUENTIAL DAMAGES OF ANY KIND ARISING FROM THE USE OF OR FAILURE TO USE
THE PRODUCT(S), WHETHER IN CONTRACT, WARRANTY, TORT, NEGLIGENCE, STRICT
LIABILITY OR OTHERWISE, INCLUDING BUT NOT LIMITED TO LOSS OF PROFITS OR REVENUE,
LOSS OF USE OF PRODUCTS, DELAYS, OR CLAIMS OF CUSTOMERS OF PURCHASER OR OTHER
THIRD PARTIES FOR SUCH OR OTHER DAMAGES. MUNTERS’ LIABILITY ON ALL CLAIMS,
WHETHER IN CONTRACT, NEGLIGENCE, TORT, STRICT LIABILITY, OR OTHERWISE FOR ANY
LOSS OR DAMAGE ARISING OUT OF, OR CONNECTED WITH AN ORDER, OR FROM THE DESIGN
OR MANUFACTURE OF PRODUCTS, SHALL IN NO CASE EXCEED THE PURCHASE PRICE.
This warranty covers replacement and repairs or adjustments made at the Munters’ factory only. If the services
of a Munters Service Technician are required at the site where the equipment or part is installed, or at any other
location other than Munters’ factory, buyer will be responsible for the cost thereof and a purchase order shall be
issued to Munters. The warranty period will not be extended by the performance of warranty repairs or
replacements.
WARRANTY FOR MUNTERS Desiccant WHEELS
Munters warrants its HoneyCombe® desiccant wheels to be free from structural defects in workmanship and
materials for a period of five years commencing thirty* (30) days from the date of shipment by Munters. (*For
specified customers the original startup report date establishes the date which will be used to calculate a
prorated replacement cost.)
The foregoing warranty does not apply to any equipment or part:
•Damage caused by misuse or any improper maintenance or contamination of the Desiccant wheel
media, or

•Damage cause by other component malfunction or operation of the equipment beyond the specified
conditions, or
•Damage caused by use or operation of such product in excess of any maximum pressures,
temperatures, or rated capacities as specified in Munters’ quotation, schedules or drawings, or
•Units that have not been installed, maintained or operated under normal conditions with competent
supervision in accordance with the equipment instruction manual, good maintenance practice, and
Munters’ recommendations; or
•Units that have been disassembled, repaired or tampered with in any way, except when such work has
been done (by an authorized service representative) in accordance with Munters’ service guidelines.
This warranty covers replacements and repairs or adjustments made at the Munters’ factory only. If the services
of a Munters Service Technician are required at the site where the equipment or part is installed, or at any other
location other than Munters’ factory, buyer will be responsible for the cost thereof and a purchase order shall be
issued to Munters. The warranty period will not be extended by the performance of warranty repairs or
replacements.
CLAIM PROCEDURES
If any defect appears in the equipment during the applicable warranty period:
•Buyer shall notify Munters of the defect in writing, including in such written notice the model, serial
number and part number of such equipment or defective part thereof, and a description of the nature of
the defect.
•After receipt of such information and a purchase order, Munters will ship a replacement, F.O.B.
Munters factory, and will invoice the buyer therefore, and for shipping charges, if applicable.
•Upon receipt of written Returned Materials Authorization from Munters, buyer shall return the
defective equipment or part to Munters with shipping charges prepaid.
•Upon receipt of the equipment or part by Munters, the cause of the failure will be analyzed. If
equipment or part is found to be defective in workmanship or material, a credit will be issued for the
cost of the replacement or repair of said equipment or part plus ground freight costs. Any special
shipping requests such as “Next Day Air” will be the customer’s responsibility and will be sent
“freight collect”.
Munters assumes no responsibility for any incidental or consequential damage to structures (including, but not
limited to, any ductwork, roofing materials, outbuilding or piping) or any other equipment caused by any
defective equipment or part or the removal or replacement thereof.
This warranty does not include delivery of materials to the job site or rigging, scaffolding, lifts or labors
necessary to install replacement equipment or parts. Buyer is responsible for removal of previously supplied or
installed materials. The warranty period will not be extended by the performance of warranty repairs or
replacements.
EXCLUSIVE REMEDY
Munters’ obligation, and buyer’s sole and exclusive remedy under this warranty, is limited to parts repair,
exchange or replacement, at Munters’ option, of any equipment determined to be defective in workmanship or
material during the applicable warranty period.
This warranty is exclusive and in lieu of all other warranties, expressed or implied, including, without
limitation, any warranty of merchantability or fitness for a particular purpose. Without limiting the generality of
the foregoing, Munters disclaims and buyer hereby waives any other claim against Munters.
This includes (whether arising by operation of law or otherwise), including any claim or liability for special,
indirect or consequential damages of any kind relating to or arising out of the equipment or any part thereof, or
the buyer’s use thereof.
Munters neither assumes nor authorizes any person to assume for it any other liability in connection with the
manufacture, sale, delivery, installation and operation of the equipment or any part thereof except as aforesaid.

This warranty is not transferable and does not cover normal wear and tear or damage caused by improper use.
Warranty is also voided if purchaser modifies desiccant wheel or original equipment in any way.
NONCONFORMITY AND DEFECTS
Munters shall not be responsible for any nonconformity or defect in or failure of a Product that: (a) is created
after such Product is delivered by Munters, including any nonconformity, defect or damage resulting from
shipment or handling by the common carrier or from Purchaser’s handling, maintenance or storage of such
Product; (b) results from materials, specifications or designs provided by Purchaser; or (c) results from
modifications to such Product by Purchaser or others.
1.2. Desiccant Dehumidifier Operating Principle
• Figure 1 shows how HCUb-Plus removes moisture from the air. The “Heart” of this system is the
Desiccant wheel. The wheel has a series of air passages or channels arranged in a honeycomb pattern.
Air can be forced through these channels in either direction.
• Passages inside wheel are impregnated or synthesized with a desiccant material. When desiccant contacts
damp air, it soaks up moisture. When desiccant is heated, it releases moisture. HCU operates with two
separate air streams. Supply air stream is air supplied to space being conditioned. Reactivation air
stream is part of condenser air stream and is used to remove heat from condenser coil and reactivate
(dry out) desiccant wheel. Supply air is pulled from outdoors into HCUb-Plus unit. This air is first
drawn through DX cooling coil that cools and removes moisture from air through condensation. Air is
then drawn through desiccant wheel. Desiccant picks up additional moisture in air. At this point,
moisture has been removed from outdoor air and stored in Desiccant wheel. Once it has been dried,
supply air is ducted into the conditioned space.
• Next is removing this moisture from wheel. Desiccant will release moisture when heated. Hot air can hold
a large amount of moisture. When hot air reaches desiccant, and moisture is released, we say desiccant
is “reactivated”.

Figure 1: Dehumidifier Operating Principle
• In the HCUb-Plus, a stream of ambient air is taken from outdoors through reactivation/condenser coil.
This heated condenser air is recycled for reactivation heat. It is then pulled through desiccant wheel.
Desiccant releases moisture into heated air stream, where it is vented outside again. This is the
reactivation process which is a continuous process as desiccant wheel rotates.
• The honeycomb material is nonmetallic and does not react to bacteria. Desiccant material is made of silica
gel, and depends on “adsorption” principle. As moisture collects, each particle of gel can bond with a
large number of water molecules. This process can be reversed by adding heat. As desiccant is heated,
it releases water to air.
• Several other parts must be added to make a working unit. HCUb-Plus has two seals, mounted on wheel
plates on each side of desiccant wheel. These seals separate two streams of air – moist air from
evaporator and heated air from condenser. Notice that two air streams move through HCUb-Plus in
opposite directions (“counter flow”). Wheel is turned by drive motor and belt. Belt tension adjusts
automatically.
• Supply air is pulled through the wheel by fan. A filter is included to keep dirt from the evaporator air and
plugging wheel. On reactivation side of system, ambient air is pulled through the wheel by a second
fan. Just upstream of wheel, this ambient air passes through condenser coil. Heat from this coil
provides energy needed to “reactivate” desiccant.
• Heated air from the first circuit is used to dry desiccant wheel and is used to provide additional cooling
and/or dehumidification when necessary. Air is drawn through the condenser coil with the reactivation
fan. This fan is controlled by a variable frequency drive (VFD) to maintain a constant head pressure
and therefore constant condensing coil leaving air temperature. Not all of the air from the condensing
coil is needed for reactivation of the wheel, so a portion of the air is exhausted through the condenser
fan.
• See Appendix B: Sequence of Operation for a detailed description of operation of HCUb-Plus.

1.3. Cooling Operating Principle
1.3.1. DX – Direct Expansion of Refrigerant
Electro-Mechanical compressor stages are used to compress the refrigerant. The hot, compressed refrigerant
circulates through a heat exchanger (condensing coil) to remove the heat created in the compression process. At
this stage the refrigerant is in liquid form. The pressurized liquid refrigerant is allowed to expand, at a
controlled rate, returning to a vapor. The vapor flows into another heat exchanger (evaporator coil), located in
the main air stream. The thermal energy in the air stream is absorbed by the evaporator coil, resulting in a
reduced air stream temperature.
If the surface temperature of the evaporator coil is below the dew point temperature of the entering air stream,
moisture will condensate out of the air, and collect on the coil surface. The leaving air stream will be cooler and
dryer as a result of this process.
1.4. Filter Principle
A typical Munters dehumidification system includes several filters. Each filter is designed to remove particles
or contaminants from the air stream. An operating dehumidification system handles large volumes of air. Even
in a relatively clean environment a unit operating without filters would quickly collect large amounts of dust
and contaminants. If this dust was allowed to collect in the Desiccant wheel, the small passages in the wheel
would become plugged, and the wheel would lose its ability to dehumidify. The heating or cooling coils in the
unit would also become coated with dust, reducing their ability to condition the air stream.
The filters used in the dehumidification system are specified by their “efficiency” and “arrestance” ratings.
“Efficiency” indicates the size of the particles which can be removed by the filter. (The filter efficiency ratings
are based on ASHRAE standard 52-76.)
The “arrestance” ratings indicate the percentage of particles of the rated size which the filter will remove. In
general, the higher the efficiency and arrestance ratings of a filter, the smaller the particles it will trap and hold.

2.Safety
The contents of this manual include suggested best working practices and procedures. These are issued for
guidance only and they do not take precedence over the individual responsibility and/or local safety regulations.
During installation and operation of this unit it is always each individual’s responsibility to consider:
•Their own and others personal safety.
•The safety of the unit through correct use of the equipment in accordance with the descriptions and
instructions provided in this manual and local/state safety guidelines.
Munters is concerned about the safety of all who use or services the HCUb-Plus unit. There are parts inside the
HCUb-Plus that can be dangerous if an untrained person tries to service the unit. Throughout this manual, we
have pointed out hazards that may occur in the use of the HCUb-Plus. We have also listed the precautions
necessary to avoid these problems.
It is recommended that the user be informed about the use of safety symbols used in this manual by reading the
following information. The relevant safety information will be listed in each chapter or section.
This manual uses three different types of warning messages to alert you of possible hazardous conditions:
Immediate hazard that will result in severe personal injury and even death.
Hazard or unsafe practice that may result in severe personal injury or
death.
Hazard or unsafe practice that could result in minor personal injury or
property damage.
Be aware of the following warnings while servicing the unit.
The HCUb-Plus is wired for 208 - 460 Volts. This unit can produce ample
voltage and current to cause severe burns, serious injury or death. Always
TURN OFF and Lock-Out all electrical power before servicing inside unit.
Only trained electricians should service the electrical components of this
unit.
The HCUb-Plus includes three or four fans (supply, reactivation and
condenser fans). Keep hands away from fan blades at all times while unit is
on. DO NOT service unit until fans have completely stopped.
The desiccant wheel used in HCUb-Plus unit is extremely heavy. Block
desiccant wheel, when inside unit is propped up, to prevent accidental
movement and/or injury to personnel.
The HCUb-Plus is designed for outdoor use. However, unit is not
waterproof or weatherproof unless all access panels are secured and all
doors are closed.
DO NOT operate unit unless all access panels and doors are in place and
secured.

3. Installation
3.1. Pre-Installation Requirements
Please note the following items related to this unit and its installation must be completed prior to scheduling the
factory technician for startup.
•All wiring (Power and Control), electrical components, control devices, and electrical service should
be completed in accordance with NFPA 70, NEC (National Fire Protection Association, National
Electrical Code). Wiring and components must also comply with all State and Local Code
requirements along with installation plans and unit specifications.
•All heating, venting, cooling, refrigeration, heat producing appliances, plumbing and piping should be
installed per UMC, ASHRAE (Uniform Mechanical Code, American Society Heating, Refrigeration
and Air Conditioning Engineers) requirements for building and energy efficiency. All components
must also comply with all State and Local Code requirements along with installation plans and unit
specifications.
•All air supply, ducting and connections must be completed per UMC, AMCA, and SMACNA
(Uniform Mechanical Code, Air Movement and Control Association - International Inc., Sheet Metal
and Air Conditioning Contractors National Association) specifications. All components must also
comply with all State and Local Code requirements along with installation plans and specifications.
3.2. Pre Checks and Inspection before Installation
The unit must be lifted by crane using all lifting points located on top of unit. The crane must be capable of
lifting weight shown on General Arrangement drawing. Failure to do so will damage the unit and void warranty.
See Figure 2 and Appendix D: General Arrangement for specific unit dimensions and weight.
For proper mounting, review all drawings; dimensions, ducting, submittal package, notes on orientation and
positioning and confirm this information before installing unit(s).
Figure 2: Lifting to prevent unit damage
Upon unit arrival, inspect immediately for signs of shipping damage. If you do notice any damage, report it to
the shipping company and to Munters immediately.
1. Check all items in the shipment carefully against the bill of lading. Be sure all of the listed items have been
received. Please check as some parts may have been shipped inside the unit.

2. Check outside of unit. Open damper for the reactivation blower. Try to turn blower by hand (be sure to use
Lock-Out/Tag-Out procedures). It should turn easily. Do the same with the process blower. (This blower
may be mounted in a plenum behind a panel.)
3. Remove the access covers on front of unit to check the following items:
•Desiccant wheel is in position and evenly supported on four rollers.
•Remove shipping strap from around wheel.
•Check seals around both faces of Desiccant wheel for any obvious signs of damage.
•Check wheel drive belt is in place and both belt and rollers are free of grease.
•Remove drive belt for wheel from drive pulley. Try to turn Desiccant wheel by hand. Wheel should
turn with some resistance and in one direction more easily than the other. Replace drive belt on drive
pulley.
•Check that reactivation filter is in place.
•During shipment, each blower motor frame is held against the mounting springs by a set of bolts. Be
sure these bolts have been removed before operating unit.
4. Check the electrical panels and controls:
•Check for any signs of damage.
•Check the tightness of all electrical connections. Carefully check the power wiring terminals.
•Be sure all control relays are firmly seated in their sockets.
5. Please refer to Technical Service Department (800-229-8557) if you have additional questions.
3.3. Positioning the Unit
It is important that the intended installation site meets the location and space requirements for the unit in order
to achieve the best possible performance and trouble-free operation.
• The Appendix shows the dimensional drawings for the HCUb-Plus units. Allow specified clearances
around the unit on all sides for maintenance access. Units should have free access to all access panels
and doors.
• Care must be taken to install unit in a location that will not allow exposure to contaminated air such as a
loading dock or oily kitchen exhaust as this could cause damage to the unit and desiccant wheel.
3.4. Installation Requirement Checklist
Check all items in this listing to insure proper installation prior to unit startup.
1. Check and install all Electrical service.
•Most units have a single point electrical hookup and a control panel with an integral non-fused
disconnect. An electrical service must be provided to accommodate the unit MCA (Minimum
Circuit Opacity). It must be suitably protected against short circuit and ground fault by a suitable
means using the MOP (Maximum Overcurrent Protection) stated on the nameplate.

•Electrical service enters the unit via camlocks directly provided on unit electrical control panel.
•If a Remote Terminal Control is to be included with this unit, be sure all mounting, panel position,
wiring, thermostats, humidistat’s etc., are properly installed using the electrical schematics that are
part of the submittal package. All connections must be completely installed for the unit to operate
correctly.
2. Check and install all Duct connections.
•Duct connections for supply and return air are made to the sides of the unit. Duct connections
must always be made to the flanges sticking out of the unit, never to the sheet metal on the unit
housing. Flexible duct connectors should be installed between the unit duct outlet and the duct.
Fans are sized to accommodate 4” total external static pressure (supply + return) from the duct
system unless otherwise specified.
•On supply discharge ductwork, allow several duct diameters of a single duct run prior to
branching of the ductwork into multiple runs to ensure even airflow and temperature/humidity
distribution. Details on ducting standards can be found in SMACNA publication "HVAC
Systems – Duct Design" and Chapter 18 of 2008 ASHRAE HVAC Systems and Equipment
Handbook.
•Most units have cooling, heating and dehumidification functions controlled by sensors located in
the conditioned space. As the controlled condition reaches the “on” set point, the required function
will energize. Wide variations in discharge temperatures can occur. During cooling mode, the
discharge temperature may be between 55F and 65F. During dehumidification temperature may
range from 65F to 85F. Makeup air units may have even greater variations. Discharge registers in
the conditioned space should be carefully located to prevent cold or hot air from blowing directly
on people and causing uncomfortable conditions.
3. Check and install all Control Wiring.
4. Check piping for refrigeration circuit.
5. Install approved “P” trap on cooling and drain pan. Please see Section 3.6.
6. Install all thermostats; humidistat’s etc.
7. Check and unlock reactivation outlet cover on end of unit. The cover is held down by a screw on
shorter units that must be removed. On taller units, the cover is held down by a cord inside the
reactivation blower housing. Loosen the blower access cover to release cord (cord will be visible,
sticking out of over). Remove the cord and retighten blower access cover. See Figures 3 and 4 for
Operating and Shipping Positions of cord/straps over louvers and damper.

Figure 3: Damper and Cords/Straps - Operating Position
Figure 4: Damper and Cords/Straps - Shipping Position
3.5. Connecting Air Supply Duct
1. Air duct connections must be completed according to U.M.C., A.M.C.A., S.M.A.C.N.A., and/or state
and local code requirements. Refer to the plans and specifications supplied with the unit.

2. This unit requires a duct from the supply air outlet to the conditioned space. Duct should be sized
appropriately and insulated.
3.6. Connecting Condensation Drain
1. The unit includes a condensation drain located on the base of the unit on the opposite side of electrical
control panel. An integrated P-trap is furnished underneath the unit base.
3.7. Connecting Electrical Service
1. Check for any signs of damage.
2. Ensure all electrical connections are tight. Carefully inspect power wiring terminals.
3. Ensure all control relays are firmly seated in their sockets.
4. Electrical service and control wiring must comply with NEC and/or state and local code requirements.
5. The HCUb-Plus is designed to operate on three-phase AC at 208-230/3/60, 460/3/60 as specified. Be
sure line voltage matches the voltage required by unit.
HCUb-Plus is wired for 208 - 575 Volts. This unit can produce enough
voltage and current to cause serious burns or death to service personnel.
Always turn off electrical power before servicing inside the unit. Follow
standard Lock-Out/Tag-Out procedures. Only licensed technicians should
service unit.
Be sure unit is connected to a power source with correct line voltage. Wire
to unit must be copper. Line voltage that is too high can cause a SHOCK
hazard and damage unit. Correct line voltage is listed on nameplate.
6. Bring in main power cable from a fused disconnect or circuit breaker directly to the camlocks provided
on the control panel. Fuse must be a time delay type. Unit FLA, MCA, and MOP are shown on the
Equipment Data Sheet.
7. Properly connect main grounding lug on control panel of HCUb-Plus to the main earth ground.
8. Before operating HCUb-Plus, ensure electrical phasing is correct. With any given combination of
wiring connections for L1, L2 and L3, there is a 50% chance that the unit's fans (not controlled by
VFD's) and compressors will be turning backwards. To check, turn on power to unit momentarily and
check for correct rotation of condenser fans and compressors are generating a pressure differential.
Fans controlled by VFD's will have correct rotation even when the unit is phase backwards. Scroll
compressors will not generate a pressure differential and make a very loud noise when phased
backwards. WARNING: RUNNING SCROLL COMPRESSORS BACKWARDS FOR EXTENDED
PERIODS OF TIME WILL RESULT IN COMPRESSOR FAILURE WHICH IS NOT COVERED
BY THE EQUIPMENT WARRANTY. It is important the HCUb-Plus is wired correctly.