Delfield MHCFA24, MHCFA34 Manuel de service

Forced Air Holding Cabinet

Original Instructions

Service Manual

This manual is updated as new information and models are released. Visit our website for the latest manual.

Part Number MHCFA_Service Manual 03/16

Safety Notices

Warning

n

Read this manual thoroughly before operating, installing
or performing maintenance on the equipment. Failure
to follow instructions in this manual can cause property
damage, injury or death.

DANGER

Do not install or operate equipment that has been
misused, abused, neglected, damaged, or altered/
modified from that of original manufactured
specifications.

DANGER

Keep power cord AWAY from HEATED surfaces. DO NOT
immerse power cord or plug in water. DO NOT let power
cord hang over edge of table or counter.

DANGER

To avoid pacemaker malfunction, consult physician or
pacemaker manufacture about effects of microwave
energy on pacemaker.

Warning

n

Authorized Service Representatives are obligated to
follow industry standard safety procedures, including,
but not limited to, local/national regulations for
disconnection / lock out / tag out procedures for all
utilities including electric, gas, water and steam.

Warning

n

Do not use electrical appliances or accessories other
than those supplied by the manufacturer.

Warning

n

Use caution when handling metal surface edges of all
equipment.

Warning

n

This appliance is not intended for use by persons
(including children) with reduced physical, sensory
or mental capabilities, or lack of experience and
knowledge, unless they have been given supervision
concerning use of the appliance by a person responsible
for their safety. Do not allow children to play with this
appliance.

Warning

n

DO NOT use this product near water – for example, near
a kitchen sink, in a wet basement, near a swimming
pool, or similar locations.

NOTE: Proper installation, care and maintenance are
essential for maximum performance and trouble-free
operation of your equipment. Visit our website www.
mtwkitchencare.com for manual updates, translations, or
contact information for service agents in your area.

Warning

n

Do Not Store Or Use Gasoline Or Other Flammable
Vapors Or Liquids In The Vicinity Of This Or Any Other
Appliance. Never use flammable oil soaked cloths or
combustible cleaning solutions, for cleaning.

Warning

n

This product contains chemicals known to the State
of California to cause cancer and/or birth defects or
other reproductive harm. Operation, installation, and
servicing of this product could expose you to airborne
particles of glasswool or ceramic fibers, crystalline
silica, and/or carbon monoxide. Inhalation of airborne
particles of glasswool or ceramic fibers is known to the
State of California to cause cancer. Inhalation of carbon
monoxide is known to the State of California to cause
birth defects or other reproductive harm.

Section 1
General Information

Section 2
Installation

Section 3
Operation

Table of Contents

Model Numbers .................................................................................................................. 5

Serial Number Information ...............................................................................................5

Warranty Information ........................................................................................................ 5

Regulatory Certifications ..................................................................................................5

Location ..............................................................................................................................7

Weight of Equipment .........................................................................................................8

Clearance Requirements ....................................................................................................8

Dimensions ......................................................................................................................... 8

Electrical Service ................................................................................................................ 9

Voltage, Watts, Rated Amperages & Power Cord Chart ............................................................9

Section 4
Maintenance

Section 5
Troubleshooting

Control Panel ....................................................................................................................12

Controls/Programming/Settings ....................................................................................12

Pre-Heat Mode ..................................................................................................................................... 12

Active Heating Mode ......................................................................................................................... 12

Programming Mode ........................................................................................................................... 13

Diagnostic Mode ................................................................................................................................ 13

Temperature View Mode ................................................................................................................. 13

Temperature Service Mode ............................................................................................................ 13

Time Button .......................................................................................................................................... 13

Load New Software Via USB ............................................................................................................13

Cleaning and Sanitizing Procedures ...............................................................................15

General .................................................................................................................................................... 15

Exterior Cleaning ................................................................................................................................. 15

Interior Cleaning .................................................................................................................................. 16

Plastic Tray Cleaning ...........................................................................................................................16

Daily Cleaning Instructions .............................................................................................................. 16

Instructions For Replacing an Air Heater .................................................................................... 18

Instructions For Replacing an Air Heater Probe ....................................................................... 18

Instructions For Replacing a Heater Pad or Pad Heater Probe ............................................ 20

Troubleshooting Chart ....................................................................................................21

Part Number MHCFA_Service Manual 03/16 3

Section 6
Controls

Control Troubleshooting .................................................................................................23

Section 7
ICC Timer Bar and Kitchen Minder

Connections ...................................................................................................................... 25

KM1 Monochrome Unit Testing & Troubleshooting ......................................................28

MHCFA22 Timer Bar Diagram ..........................................................................................30

MHCFA23 Timer Bar Diagram ..........................................................................................31

MHCFA24 Timer Bar Diagram ..........................................................................................32

MHCFA34 Timer Bar Diagram ..........................................................................................34

MHCFA42 Timer Bar Diagram ..........................................................................................35

Section 8
Charts

Zone Diagrams & Heating Element Specifications ........................................................37

System Layout ..................................................................................................................38

I/O Board ........................................................................................................................... 39

I/O Board Connections .....................................................................................................40

Section 9
Wiring Diagrams

Table of Contents (continued)

MHCFA22 - Domestic 2x2.................................................................................................43

MHCFA22EX - Export 2x2 ................................................................................................. 45

MHCFA23 & MHCFA24 - Domestic 2x3 & 2x4 .................................................................47

MHCFA23EX & MHCFA24EX - Export 2x3 & 2x4 .............................................................50

MHCFA34 - Domestic 3x4.................................................................................................54

MHCFA34EX - Export 3x4 ................................................................................................. 59

MHCFA42EX - Export 4x2 ................................................................................................. 64

4 Part Number MHCFA_Service Manual 03/16

Section 1

General Information

Model Numbers

Domestic Models

MHCFA22

MHCFA23

MHCFA24

MHCFA34

Export Item/SKU Export Models

MHCFA22EX MHCFA22

MHCFA23EX MHCFA23

MHCFA24EX MHCFA24

MHCFA34EX MHCFA34

MHCFA42EX MHCFA42

Model Suffix

Control Box Time Bar Sided

Suffix

Primary

BP1 X X X

BP2 X X X

BS1 X X X

BS2 X X X

BP1R X X X

BP2R X X X

BS1R* X X X

BS2R* X X X

BP1A X X X

BP2A X X X

BS1A X X X

BS2A X X X

Secondary

None

R/G Light

NOTE: * Suffixes are not available for MHCFA34 and
MHCFA34EX.

A/N

Single

Dual

Serial Number Information

MHCFA holding cabinet serial and model numbers are
located on the data plate. Data plates are located on the
bottom and the right end of the unit.

Always have the serial number of your unit available
when calling for parts or service.

For ICC time bar and kitchen minder connection questions
and issues call - ICC Tech Division 631-673-5100 or 877-422­8788 (North America only).

Warranty Information

Visit http://www.mercoproducts.com/minisite/service/
warranty_info to:

• Register your product for warranty.

• Verify warranty information.

• View and download a copy of your warranty.

Regulatory Certifications

Domestic Models are certified by:

• Underwriters Laboratories Sanitation

• Underwriters Laboratories (UL)

• Underwriters Laboratories of Canada (CUL)

Export Models are certified by:

• Underwriters Laboratories Sanitation

• European Conformity

• Technical Inspection Association

Part Number MHCFA_Service Manual 03/16 5

General Information Section 1

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6 Part Number MHCFA_Service Manual 03/16

Section 2

Installation

DANGER

Installation must comply with all applicable fire and
health codes in your jurisdiction.

DANGER

Legs must be installed and the legs must be screwed in
completely.

DANGER

Use appropriate safety equipment during installation
and servicing.

Warning

n

Only trained and authorized service personnel or store
manager should access the service screens. If changes
to these settings are made incorrectly they will cause
the unit to malfunction.

Location

Warning

n

This equipment must be positioned so that the plug is
accessible unless other means for disconnection from
the power supply (e.g., circuit breaker or disconnect
switch) is provided.

Warning

n

Adequate means must be provided to limit the
movement of this appliance without depending on or
transmitting stress to the electrical conduit or gas lines.

Warning

n

To avoid instability the installation area must be capable
of supporting the combined weight of the equipment
and product. Additionally the equipment must be level
side to side and front to back.

Warning

n

This equipment is intended for indoor use only. Do not
install or operate this equipment in outdoor areas.

Caution

,

Do not position the air intake vent near steam or heat
exhaust of another appliance.

The location selected for the equipment must meet the
following criteria. If any of these criteria are not met, select
another location.

• Holding cabinets are intended for indoor use only.

• The location MUST be level, stable and capable of
supporting the weight of the equipment.

• The location MUST be free from and clear of
combustible materials.

• Equipment MUST be level both front to back and side to
side.

• Position the equipment so it will not tip or slide.

• Recommended air temperature is 41° - 86°F (5° - 30°C) .

• Proper air supply for ventilation is REQUIRED AND
CRITICAL for safe and efficient operation. Refer to
Clearance Requirements chart on page 8.

• Do not obstruct the flow of ventilation air. Make sure the
air vents of the equipment are not blocked.

Part Number MHCFA_Service Manual 03/16 7

Installation Section 2

Weight of Equipment

Domestic Model Export Item/SKU Weight

MHCFA22 MHCFA22EX 40lbs/18kg

MHCFA23 MHCFA23EX 65lbs/29kg

MHCFA24 MHCFA24EX 85lbs/39kg

MHCFA34 MHCFA34EX 125lbs/57kg

MHCFA42EX 85lbs/39kg

Clearance Requirements

DANGER

Minimum clearance requirements are the same for
noncombustible locations as for combustible locations.
The flooring under the appliance must be made of a
noncombustible material.

DANGER

Risk of fire/shock. All minimum clearances must be
maintained. Do not obstruct vents or openings.

Sides/Back

1.0” (25mm)

Dimensions

Domestic Model,
Export Item/SKU

MHCFA22,

MHCFA22EX

MHCFA23,

MHCFA23EX

MHCFA24,

MHCFA24EX

MHCFA34,

MHCFA34EX

MHCFA42EX 19.56”

Length Depth Height

19.56”

(497mm)

29.57”

(751mm)

36.45”

(926mm)

36.45”

(926mm)

(497mm)

12.31”

(313mm)

12.31”

(313mm)

12.31”

(313mm)

12.31”

(313mm)

12.31”

(313mm)

11.24”

(285mm)

11.24”

(285mm)

11.24”

(285mm)

15.70”

(399mm)

20.32”

(516mm)

8 Part Number MHCFA_Service Manual 03/16

Section 2 Installation

Electrical Service

VOLTAGE, WATTS, RATED AMPERAGES & POWER CORD
CHART

DANGER

Check all wiring connections, including factory
terminals, before operation. Connections can become
loose during shipment and installation.

All electrical work, including wire routing and grounding,
must conform to local, state and national electrical codes.
The following precautions must be observed:

• The equipment must be grounded.

• A separate fuse/circuit breaker must be provided for

DANGER

Copper wire suitable for at least 167°F (75°C) must be
used for power connections.

each unit.

• A qualified electrician must determine proper wire size
dependent upon location, materials used and length
of run (minimum circuit ampacity can be used to help

Warning

n

This appliance must be grounded and all field wiring
must conform to all applicable local and national
codes. Refer to rating plate for proper voltage. It is the
responsibility of the end user to provide the disconnect
means to satisfy the authority having jurisdiction.

select the wire size).

• The maximum allowable voltage variation is ±10% of
the rated voltage at equipment start-up (when the
electrical load is highest).

• Check all green ground screws, cables and wire
connections to verify they are tight before start-up.

Units with plugs are supplied with approximately 9ft cords,
maximum 10ft.

Domestic Model Voltage, Cycle, Phase Watts Amps Plug

MHCFA22 120, 60, 1 1920 16.0 5-20P

MHCFA23

MHCFA24

MHCFA34

208-230, 60, 1
208-230, 60, 1

208, 60, 1

3174 13.8 6-20P

3680 16.0 6-20P

3120 15.0 6-20P

Export Item/SKU Voltage, Cycle, Phase Watts Amps Plug

MHCFA22EX 200-240, 50/60, 1 2472 9.9-10.3 Varies per destination

MHCFA23EX 200-240, 50/60, 1 2856 11.4-11.9 Varies per destination

MHCFA24EX 200-240, 50/60, 1 2784 9.8-11.6

MHCFA34EX 200-240, 50/60, 1 3072 10.1-12.8

MHCFA42EX 200-240, 50/60, 1 2784 9.8-11.6

16A pin/sleeve

(IEC-60309 16A, 3-pin plug)

16A pin/sleeve

(IEC-60309 16A, 3-pin plug)

16A pin/sleeve

(IEC-60309 16A, 3-pin plug)

Part Number MHCFA_Service Manual 03/16 9

Installation Section 2

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10 Part Number MHCFA_Service Manual 03/16

Section 3

Operation

DANGER

The on-site supervisor is responsible for ensuring that
operators are made aware of the inherent dangers of
operating this equipment.

DANGER

Do not operate any appliance with a damaged cord
or plug. All repairs must be performed by a qualified
service company.

DANGER

Never stand on the unit! They are not designed to
hold the weight of an adult, and may collapse or tip if
misused in this manner.

Warning

n

Do not contact moving parts.

Warning

n

All covers and access panels must be in place and
properly secured, before operating this equipment.

Warning

n

Liquids such as water, coffee, or tea can be overheated
beyond the boiling point without appearing to be
boiling due to surface tension of the liquid. Visible
bubbling or boiling when the container is removed from
the microwave oven is not always present. THIS COULD
RESULT IN VERY HOT LIQUIDS SUDDENLY BOILING OVER
WHEN A SPOON OR OTHER UTENSIL IS INSERTED INTO
THE LIQUID. To reduce the risk of injury to persons: Do
not overheat the liquid. Stir the liquid both before and
halfway through heating it.

Warning

n

DO NOT use the cavity for storage. DO NOT leave paper
products, cooking utensils, or food in the cavity when
not in use.

Caution

,

Do not block the supply and return air grills or the air
space around the air grills. Keep plastic wrappings,
paper, labels, etc. from being airborne and lodging in
the grills. Failure to keep the air grills clear will result in
unsatisfactory operation of the system.

Caution

,

Some products such as whole eggs or sealed containers
– for example, closed glass jars – are able to explode
and SHOULD NOT be HEATED in this oven. Pressure may
build up and erupt. Pierce yolk with fork or knife before
cooking. Pierce skin of potatoes, tomatoes, and similar
foods before cooking with microwave energy. When
skin is pierced, steam escapes evenly.

Caution

,

DO NOT cover racks or any other part of the oven with
metal foil. Airflow restriction will cause overheating of
the oven.

Warning

n

Do not heat sealed containers or plastic bags in oven.
Food or liquid could expand quickly and cause container
or bag to break. Pierce or open container or bag before
heating.

Warning

n

Racks, utensils, rack guides, and oven surfaces may
become hot during or after use. Use utensils or
protective clothing, like pan grips or dry oven mitts,
when necessary to avoid burns.

Part Number MHCFA_Service Manual 03/16 11

Operation Section 3

Control Panel

Left Display

Time Button

(nonfunctional)

Temperature

Button

Power Button

Right
Display

Program
Button

Day Part Button
Up Button

Enter Button

Cancel Button

Down Button

Controls/Programming/Settings

The Merco Holding Cabinet has been designed to afford
foodservice operators the ability to cook menu components
in advance and then gently store that product in the
holding bins until an order is received. Once that order has
been placed, the crew can assemble the order using hot
and fresh menu components from the holding bins. This
allows for operators to serve to order, helping increase
speed of service while maintaining high product quality
standards.

The holding bin controller is, at all times, operating in one
of the following modes. The indents indicate the sub­modes. Sub-modes are defined based on the navigation
to the mode. I.e., to get to diagnostic mode you must be in
active heating mode then enter programming mode.

• Pre-Heat Mode

• Active Heating Mode

- Programming Mode

» Diagnostic Mode

- Temperature View Mode

» Service Temperature Mode

PREHEAT MODE

The displays shall scroll the message Pre-Heating
repeatedly during pre-heat mode. The LED corresponding
to the active Day Part menu configuration will be on. Once
a heater has reached 180°F (82°C), it will be regulated to
the set point. The PRE-HEAT mode will be terminated when
all of the heaters have reached 180°F (82°C) OR 15 minutes
have passed.

During Pre-Heat mode, all button presses will be ignored
except the check mark button. If the check mark button
is pressed and held for (3) seconds, the displays will scroll
the message, Cancel Pre-Heat? If the check mark button
is pressed again, the unit will Cancel the Pre-Heat mode
and enter Active Heating Mode. If the cancel (X) button is
pressed, the unit shall return to Pre-Heat Mode.

ACTIVE HEATING MODE

This is the active heating mode of operation. In active
heating mode the displays will be blank and the day part
LED light will be ON.

Typical Operator Actions

Action Instructions

Turn Unit On Push Power button.

Load bin with
product

Empty bin Pull out tray and remove product.

Pull out tray, load product and reinsert
tray.

Reinsert tray.

When the unit is first powered ON, the software version
will scroll across the display. It will then begin to preheat.
Allow it to preheat for 15 minutes, the display will scroll
Preheating.

During active heating mode, press enter to scroll the
software version on the display.

12 Part Number MHCFA_Service Manual 03/16

Section 3 Operation

PROGRAMMING MODE

Press the program button to enter the programming mode.
Zone and temperature will display. The zone will flash,
press the up or down button to reach the desired zone.
Press the day part button until the desired day part LED is
ON. Press the temperature button and both the zone and
temperature will flash. Press the up or down button to reach
the desired temperature. The program button LED light will
flash, indicating a program change has occurred. Press enter
or the temperature button to return to the zone selection,
the zone will flash. Press the program button to exit.

DIAGNOSTIC MODE

From Programming mode, press the program button and
hold for 3 seconds to enter Diagnostic Mode.

The software shall track the state of each thermocouple and
the state of the thermocouple reading compared to the set
point.

If the software finds an error, it will begin to time it. When
the timer reaches 15 minutes, an error code(s) will display
(flash) on the screen. This shall continue indefinitely.

Turning Off and On a unit will clear all TC State Display flags
and reset all TC temp timer’s to 0.

TC Display Codes

Left Display Right Display

ZaEr b_cd

a b c d

Zone Location

with Error

1
2
3
4
5
6
7
8

Section of
Zone with

Error

U=Upper
L=Lower

Thermocouple

State

0 = Ok
1 = Shorted
2 = Open

Thermocouple

reading compared

to Set point

0 = Within Range
1 = Below Range
2 = Above Range

TEMPERATURE VIEW MODE

Enter the temperature view mode by pressing the
temperature button. The average temperature in the first
zone will be displayed. Press the up or down button to scroll
through zones. Zones progress from left to right, top to
bottom. Press the temperature button or the cancel button
to exit.

TEMPERATURE SERVICE MODE

Press the temperature button or when already in the
temperature view mode press and the hold temperature
button to display the actual thermocouple temperature.
This is called the temperature service mode. Press the up
or down button to scroll through zones. U stands for upper,
L for lower. Press the temperature button or the cancel
button to exit.

During temperature service mode if the DOWN button
is held for 3 seconds the temperature display shall
be replaced with the word OFF, and the zone shall be
considered OFF. If a zone is considered OFF, the triac
outputs shall be set to off regardless of the thermocouple
feedback for that zone. No alarms shall be initiated for a
zone that is off.

TIME BUTTON

The time button has no function currently. Time will be
displayed on the Timer Bar.

LOAD NEW SOFTWARE VIA USB

Firmware file must be loaded onto the top level of USB
instead of in a folder.

While the unit is OFF, insert the new software USB into the
port. Turn the unit ON by pushing the power button. The
unit will detect the software and begin installation. The
display will scroll Updating Firmware, then Preheating.
When Preheating is scrolling it is clear to remove the USB.

USB Port

Part Number MHCFA_Service Manual 03/16 13

Operation Section 3

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14 Part Number MHCFA_Service Manual 03/16

Section 4

Maintenance

DANGER

All utility connections and fixtures must be maintained
in accordance with Local and national codes.

DANGER

It is the responsibility of the equipment owner to
perform a Personal Protective Equipment Hazard
Assessment to ensure adequate protection during
maintenance procedures.

DANGER

Failure to disconnect the power at the main power
supply disconnect could result in serious injury or death.
The power switch DOES NOT disconnect all incoming
power.

DANGER

Always discharge the ht capacitors before working on
the oven using a suitably insulated 10mo resistor.

DANGER

Disconnect electric power at the main power disconnect
for all equipment being serviced. Observe correct
polarity of incoming line voltage. Incorrect polarity can
lead to erratic operation.

Cleaning and Sanitizing Procedures

GENERAL

You are responsible for maintaining the equipment
in accordance with the instructions in this manual.
Maintenance procedures are not covered by the warranty.

Maintenance Daily After Prolonged

Shutdown

Exterior X X X

Interior X X X

Holding Bin, Bin Lid

& Jet Plate

Plastic Tray X X X

EXTERIOR CLEANING

Never use a high-pressure water jet for cleaning or hose
down or flood interior or exterior of units with water. Do
not use power cleaning equipment, steel wool, scrapers
or wire brushes on stainless steel or painted surfaces.

Never use an acid based cleaning solution on exterior
panels! Many food products have an acidic content,
which can deteriorate the finish. Be sure to clean the
stainless steel surfaces of ALL food products.

X X X

Warning

n

Caution

,

At Start-Up

Warning

n

When using cleaning fluids or chemicals, rubber gloves
and eye protection (and/or face shield) must be worn.

Caution

,

Maintenance and servicing work other than cleaning as
described in this manual must be done by an authorized
service personnel.

Part Number MHCFA_Service Manual 03/16 15

The stainless steel outer case requires nothing more than
a daily wiping with a damp cloth. If, however, an excessive
amount of food particles/grease are allowed to collect, a
non-abrasive cleaner (hot sudsy water) may be used. Wipe
dry with a clean, soft cloth.

Always rub with the “grain” of the stainless steel to avoid
marring the finish. Never use steel wool or abrasive pads
for cleaning. Never use chlorinated, citrus based or abrasive
cleaners.

Stainless steel exterior panels have a clear coating that
is stain resistant and easy to clean. Products containing
abrasives will damage the coating and scratch the panels.
Daily cleaning may be followed by an application of
stainless steel cleaner which will eliminate water spotting
and fingerprints. Early signs of stainless steel breakdown
are small pits and cracks. If this has begun, clean thoroughly
and start to apply stainless steel cleaners in attempt to
restore the steel.

Maintenance Section 4

INTERIOR CLEANING

Caution

,

Do not use caustic cleaners on any part of the oven or
oven cavity . Use mild, non abrasive soaps or detergents,
applied with a sponge or soft cloth. Never use sharp
implements or harsh abrasives on any part of the oven.

The product holding bin, bin lid and jet plate may be
cleaned via dishwasher or with warm soapy water. Care
must be taken to prevent water or cleaning compounds
from getting on internal parts, especially the switches on
the control panel.

PLASTIC TRAY CLEANING

Caution

,

Environmental stress cracking can occur, proper dilution
and rinsing per detergent manufacturers’ directions are
mandatory.

Food-approved detergents can be used if they are diluted
per manufacturers’ directions and adequately rinsed
away prior to high temp drying cycle. Basic alcohols such
as isopropyl are acceptable for hard-to-remove stains.
Otherwise, do not use organic solvents.

DAILY CLEANING INSTRUCTIONS

Unit must be cool to touch and disconnected from
power source.

1. Wipe the stainless steel outer case with a damp cloth,
rubbing with the grain of the steel. If an excessive
amount of food particles/grease has collected, hot
sudsy water (non-abrasive) may be used.

2. Remove bins.

16 Part Number MHCFA_Service Manual 03/16

Section 4 Maintenance

3. Twist each jet plate assembly lever counter clockwise
into the horizontal unlocked position.

4. Remove jet plate assemblies.

7. Reinstall the cleaned jet plate assemblies.

8. Twist each jet plate assembly lever clockwise into the
vertical locked position.

5. The product holding bins, bin lids and jet plates may be
cleaned via dishwasher or with warm soapy water.

6. Wipe the interior bottom with a damp cloth. If,
however, an excessive amount of food particles/grease
has collected, hot sudsy water (non-abrasive) may be
used.

9. Reinstall the cleaned bins.

10. Plug the unit in.

Part Number MHCFA_Service Manual 03/16 17

Maintenance Section 4

INSTRUCTIONS FOR REPLACING AN AIR HEATER

1. Remove end panel.

2. Disconnect heater hot wire from I/O board and neutral
wire from terminal block.

3. Remove the fasteners securing the air heater to the
chassis.

4. Install new air heater with fasteners.

5. Reconnect electrical and reinstall end panel.

INSTRUCTIONS FOR REPLACING AN AIR HEATER
PROBE

Air heater probes are located in the panel above the zone.

Top Zone Air Heater Probe Replacement

1. Remove the unit top.

2. Remove the insulation.

3. Remove probe, it will be thoroughly taped in place.

4. Tape a new probe in it’s place and put the machine
back together.

Lower Zone Air Heater Probe Replacement

These air heater probes are taped in the aluminum plate above
the zone.

1. Remove the Timer Bar above the zone.

2. Remove center divider above the zone via two screws
(US Models).

3. Remove both end clips above the zone via two screws.

4. Remove end panels.

5. From each side remove screws holding in aluminum
plate above zone.

18 Part Number MHCFA_Service Manual 03/16

Section 4 Maintenance

6. From both sides unplug heaters and probes associated
with aluminum plate above zone. Hot wires are
plugged into the I/O board and neutral wires are
connected to the terminal block.

7. Raise aluminum plate and insulation to gain access to
air heater probe below.

8. Remove and replace air heater probe.

9. Put unit back together.

Part Number MHCFA_Service Manual 03/16 19

Maintenance Section 4

INSTRUCTIONS FOR REPLACING A HEATER PAD OR
PAD HEATER PROBE

Pad heater probes are located in the pad heater assembly.

1. Remove the Timer Bar that is in front of the pad heater.
It will be below the zone.

2. Remove jet plates above pad heater.

6. From each side remove screws holding in aluminum
plates.

7. From both sides unplug heaters and probes associated
with the heater pad. Hot wires are plugged into the I/O
board and neutral wires are connected to the terminal
block.

3. Remove center divider above heater pad via two screws
(US Models).

4. Remove both end clips above heater pad via two
screws.

5. Remove end panels.

8. Pull the aluminum plate out carefully.

9. Heater Probe Replacement

Flip the aluminum plate over. Peel the probe out of the
heater pad. The probe has brown insulation. Tape a new
probe in it’s place

10. Heater Pad Replacement

Flip the aluminum plate over. Peel the heater pad off
and stick a new one on.

11. Put the machine back together.

20 Part Number MHCFA_Service Manual 03/16

Section 5

Troubleshooting

Troubleshooting Chart

Problem Cause Correction

Cabinet not

running

Cabinet

temperature is too

high

Cabinet

temperature is too

low

Fuse blown or circuit breaker tripped. Replace fuse or reset circuit breaker.

Power cord unplugged. Plug in power cord.

Thermostat set too high. Set thermostat to lower temperature.

Main power switch turned off. Turn main power switch on.

Thermostat set too high. Set thermostat to lower temperature.

Poor air circulation in cabinet. Re-arrange product to allow proper air circulation.

Exterior thermometer is out of calibration. Re-calibrate thermometer.

Jet plate out of unit. Reinstall jet plate.

Pans out of unit. Reinstall pans in unit.

Part Number MHCFA_Service Manual 03/16 21

Troubleshooting Section 5

THIS PAGE INTENTIONALLY LEFT BLANK

22 Part Number MHCFA_Service Manual 03/16

Section 6

Controls

Control Troubleshooting

TC Display Codes

Left Display Right

Display

ZaEr b_cd

a b c d

Zone Location with Error Section of Zone with Error Thermocouple State Thermocouple reading

compared to Set point

1
2
3
4
5
6
7
8

U=Upper

L=Lower

Upper Zone Thermocouple Shorted - Right Display Error
Code U_1d

1. Remove the jet plate and inspect the air heater probe
near the upper baffle.

2. If end of probe is touching metal, move it. If the error
clears, repair the end by adding high temp heat tape
rated at 392°F or silicone sleeve to the probe end.

3. If moving or taping probe end doesn’t fix error code,
short is some place else.

4. Remove side panel.

5. Inspect probe wire where it connects to I/O board.

6. Check probe continuity to chassis.

7. Check continuity through probe.

8. Swap probe with error with an error free probe.
Thermocouple state checks every 5 seconds. If error
location switches, replace probe.

Lower Zone Thermocouple Shorted - Right Display Error
Code L_1d

1. There is no physical inspection for the hot end of the
pad heater probe.

2. Inspect probe wire where it connects to I/O board.

3. Check probe continuity to chassis. If probe is grounded
to chassis replace probe.

4. Swap probe with error with an error free probe.
Thermocouple state checks every 5 seconds. If error
location switches, replace probe or pad.

Thermocouple Is Open - Right Display Error Code b_2d

1. Unplug the probe from the I/O board.

2. Check that end of probe has a ramp shape and there is

3. Plug probe back into I/O board, confirm connection

4. Check continuity through probe, if probe is open probe

5. Swap probe with error with an error free probe.

0 = Ok

1 = Shorted

2 = Open

0 = Within Range
1 = Below Range
2 = Above Range

no visible oxidation.

snaps.

must be replaced.

Thermocouple state checks every 5 seconds. If error
location switches, replace probe.

Part Number MHCFA_Service Manual 03/16 23

Controls Section 6

Thermocouple Reading is Below or Above Set Point ­Right Display Error Code b_c1 or b_c2

1. Document all temperature readings for unit, each zone,
upper and lower.

2. If the zone probes are switched, there will be two
errors, one high and one low.

3. Check the I/O boards where the probes with errors plug
in. There is yellow insulation jacket on the air probes
and brown insulation jacket on the pad probes. Check
that the probes alternate (yellow brown yellow brown)
and are plugged in properly.

4. Heater outputs could be swapped, there will be two
errors. Air heaters have yellow fiberglass wire. Pad
heaters have brown silicone wire. Check that the wires
alternate (fiberglass silicone fiberglass silicone).

5. The I/O board triac could be shorted or open. An
orange LED is associated with each triac, it signals if the
triac should be on or off.

6. Isolate each triac wire and check the amperage.

• If the triac is supposed to be open and there is
no current, the problem could be a heater. Check
continuity through heating element.

• If the triac light does not match the amperage,
the triac is failing and the I/O board needs to be
replaced.

• Check input and output of triac, this could signal an
I/O board failure.

24 Part Number MHCFA_Service Manual 03/16

Kitchen Minder

PHU 1

PHU 7

COM3 COM2 COM1

PHU 2

PHU 6

PHU 8

PHU 9

PHU 5

PHU 3

BOH

Serial Port

Programming

Power

2x4,4x2,2x3 or 2x2

2x4,4x2,2x3 or 2x2

2x4, 4x2, 2x3 & 2x2 PPHU and SPHU mix and

devices) Up to 9 PHU’s are supported

KM Power

Section 7

ICC Timer Bar and Kitchen Minder

For ICC Timer Bar and Kitchen Minder connection questions and issues call - ICC Tech Division 631-673-5100 or
877-422-8788.

Connections

Merco PHU’s with Alpha/Numeric Timer Bars to a Kitchen Minder system.

Use one of the following 3 diagrams that best fits your restaurant configuration.

It also is possible to mix and match from COM1, COM2 and COM 3 of the 3 diagrams. Any Secondary PHU may be left out
and any full COM port can be left out but must be filled COM1 first, then 2, then 3.

match connection diagram (rear perspective of

Computer
RS-232

Outlet

Supply

Primary PHU’s

(PPHU)

PHU 4

Secondary PHU’s

(SPHU)

= ICC 6 position flat cable
up to 25’

= ICC or any standard
CAT5 Cable up to 50’

Part Number MHCFA_Service Manual 03/16 25

ICC Timer Bar and Kitchen Minder Section 7

2x4, 4x2, 2x3 or 2x2

3x4 PPHU and 2x4, 4x2, 2x3, 2x2 SPHU mix

Kitchen Minder

PHU 1 Bottom
PHU 2 Top

COM3 COM2 COM1

PHU 3

PHU 9

PHU 6

BOH

Serial Port

Programming

Power

3x4 Primary PHU’s

KM Power

PHU 4 Bottom
PHU 5 Top

PHU 7 Bottom
PHU 8 Top

and match connection diagram (rear

perspective of devices) Up to 6 physical PHU’s

are supported

Computer
RS-232

Outlet

Supply

(PPHU)

Secondary PHU’s

(SPHU)

= ICC 6 position flat cable
up to 25’

= ICC or any standard
CAT5 Cable up to 50’

26 Part Number MHCFA_Service Manual 03/16

Section 7 ICC Timer Bar and Kitchen Minder

3x4 Secondary PHU’s

3x4 PPHU and 3x4 SPHU connection diagram

Kitchen Minder

PHU 1 Bottom
PHU 2 Top

COM3 COM2 COM1

PHU 2 Top
PHU 3 Bottom

BOH

Serial Port

Programming

Power

3x4 Primary PHU’s

KM Power

PHU 4 Bottom
PHU 5 Top

PHU 7 Bottom
PHU 8 Top

PHU 5 Top
PHU 6 Bottom

PHU 8 Top
PHU 9 Bottom

(rear perspective of devices) Up to 6 physical

PHU’s are supported

Computer
RS-232

Outlet

Supply

(PPHU)

(SPHU)

= ICC 6 position flat cable
up to 25’

= ICC or any standard
CAT5 Cable up to 50’

Part Number MHCFA_Service Manual 03/16 27

ICC Timer Bar and Kitchen Minder Section 7

KM1 Monochrome Unit Testing & Troubleshooting

1.1 - Testing connections

1.1.1 - Product Location Test

1.1.2 - On the KM, press the Menu key

1.1.3 - Use the down arrow to highlight Product Location and press Select key

1.1.4 - The following screen will appear:

1.1.5 - Press the Continue soft key

1.1.6 - On the KM PHU1 will display 8 pans referenced from the front of the PPHU connected to COM1 of the KM

1.1.6.1 - The upper left corner on the KM screen will be highlighted

1.1.6.1.1 - All Timer Bar LED’s will be unlit except:

1.1.6.1.2 - On a 2x4 or 4x2 PPHU, the top left pan will illuminate solid red

1.1.6.1.3 - On a 2x3 PPHU press the Select key once

1.1.6.1.3.1 - The pan on the KM will move one pan to the right

1.1.6.1.3.2 - The TB LED on the 2x3 PPHU top left pan will illuminate solid red

1.1.6.1.4 - On a 2x2 PPHU press the Select key twice

1.1.6.1.4.1 - The pan on the KM will move two pans to the right

1.1.6.1.4.2 - The Timer Bar LED on the 2x2 PPHU top left pan will illuminate solid red

1.1.6.1.5 - On a 3x4 PPHU, the middle left pan will illuminate solid red

1.1.6.1.5.1 - Press the Next soft key to advance to PHU2

1.1.6.1.5.2 - The top left pan of the 3x4 will illuminate solid red

1.1.7 - Continue in the same manner for all PHU’s connected to the KM based on the diagrams above

1.1.8 - Press the Product Status key

1.1.9 - The KM will go to Product Status screen

1.1.10 - The restaurant manager should program PC Minder with the correct products for each PHU and transfer the
data to the Kitchen Minder

28 Part Number MHCFA_Service Manual 03/16

Section 7 ICC Timer Bar and Kitchen Minder

1.2 - Troubleshooting

1.2.1 - If a PPHU Timer Bar displays NOKM

1.2.1.1 - Check the CAT5 connection from the KM to the PPHU

1.2.1.2 - Test the CAT5 cable with a cable tester or use a known good cable

1.2.1.3 - If the connection and cable are OK, call Merco or ICC for support

1.2.2 - If a SPHU displays NOBB

1.2.2.1 - Check that the PPHU is powered on

1.2.2.2 - Check the 6 position data connection from the PPHU to the SPHU

1.2.2.3 - Check the 6 position cable with a cable tester or use a known good cable

1.2.2.4 - If the PPHU is powered on, the connection and cable are OK, call Merco or ICC for support

1.3 - End of document

Part Number MHCFA_Service Manual 03/16 29

ICC Timer Bar and Kitchen Minder Section 7

1:1 CONNECTOR

CABLE

12.00"

BLACK

WARMER
CONTROL

ICC# 681-6X6-12

MHCFA22 Timer Bar Diagram

NOTE: “Warmer Control” on diagram is the I/O board.

BACK ICC P/N980105-2X2#

FRONT ICC P/N980105-2X2#

CABLE ASS'Y
ICC# 801195

BLACK

BLACK

12VAC

XFMR IN PHU

PRODUCT HOLDING UNIT 1

J5

J1

WMR 2

J2

J3

PHU II HUB CONTROL BOARD
A/N WITH TEMP, 2H
ICC # 810195-80#

J4

WMR 1

WMR 3

WARMER
CONTROL

CABLE CAT 5

ICC# 681-8X8-12

12.00"

877-ICC-8788

877-ICC-8788

6.00" +/- 1.00"

ICC# 681-6X6-12

CABLE

ICC# 681-6X6-12

12.00"

ICC# 681-6X6-12

6.00" +/- 1.00"

WARMER
ADAPTER

ICC# 810004

CABLE

12.00"

CABLE

12.00"

1:1 CONNECTOR

BACK ICC P/N980105-2X2#

FRONT ICC P/N980105-2X2#

F

B

CABLE ASS'Y
ICC# 801195

BLACK

BLACK

J1

J2

TO STATION
INTERFACE BOX

CABLE

12.00"

VCC

SECONDARY PHU POWER
SUPPLY BOARD
ICC 810680#-1

1:1 CONNECTOR

CABLE

ICC# 681-6X6-96

96.00"

1:1 CONNECTOR

CABLE

ICC# 681-6X6-12

12.00"

WARMER
CONTROL

WARMER
ADAPTER
ICC# 810004

12VAC

XFMR IN PHU

ICC# 681-6X6-12

F

B

J4

KEYBD
FRONT

J3

KEYBD
BACK

877-ICC-8788

6.00" +/- 1.00"

877-ICC-8788

6.00" +/- 1.00"

PRODUCT HOLDING UNIT 2

1:1 CONNECTOR

CABLE

ICC# 681-6X6-96

96.00"

CAT 5

CABLE TO KITCHEN MINDER

ICC# 681-6X6-12

1:1 CONNECTOR

BACK ICC P/N980105-2X2#

FRONT ICC P/N980105-2X2#

CABLE ASS'Y
ICC# 801195

BLACK

BLACK

XFMR IN PHU

WARMER
CONTROL

CABLE

12.00"

WARMER
ADAPTER
ICC# 810004

12VAC

CABLE

ICC# 681-6X6-12

12.00"

F

B

J1

J2

TO STATION
INTERFACE BOX

VCC

SECONDARY PHU POWER SUPPLY BOARD
ICC 810680#-1

KEYBD
FRONT

KEYBD

BACK

J4

J3

877-ICC-8788

877-ICC-8788

6.00" +/- 1.00"

6.00" +/- 1.00"

PRODUCT HOLDING UNIT 3

30 Part Number MHCFA_Service Manual 03/16

Section 7 ICC Timer Bar and Kitchen Minder

1:1 CONNECTOR

CABLE

12.00"

ICC# 681-6X6-12

WARMER
CONTROL

MHCFA23 Timer Bar Diagram

NOTE: “Warmer Control” on diagram is the I/O board.

BACK ICC P/N 980105-2X3#

FRONT ICC P/N 980105-2X3#

CABLE ASS'Y
ICC# 801195

BLACK

BLACK

12VAC

XFMR IN PHU

PRODUCT HOLDING UNIT 1

WARMER
CONTROL

J2

J1

PHU II HUB CONTROL BOARD

A/N WITH TEMP, 2H
ICC # 810195-80#

J5

WMR 1

J4

WMR 2

J3

WMR 3

ICC# 681-8X8-12

CABLE CAT 5

12.00"

877-ICC-8788

8
7
7

-
I
C
C

-
8
7
8
8

877-ICC-8788

877-ICC-8788

6.00" +/- 1.00"

ICC# 681-6X6-12

CABLE

ICC# 681-6X6-12

12.00"

ICC# 681-6X6-12

6.00" +/- 1.00"

F

B

WARMER
ADAPTER

ICC# 810004

CABLE

12.00"

1:1 CONNECTOR

CABLE

ICC# 681-6X6-96

96.00"

CABLE

12.00"

1:1 CONNECTOR

1:1 CONNECTOR

CAT 5

BACK ICC P/N 980105-2X3#

FRONT ICC P/N 980105-2X3#

1:1 CONNECTOR

CABLE

ICC# 681-6X6-12

12.00"

CABLE TO KITCHEN MINDER

BACK ICC P/N 980105-2X3#

FRONT ICC P/N 980105-2X3#

BLACK

BLACK

WARMER
CONTROL

WARMER
ADAPTER
ICC# 810004

PRODUCT HOLDING UNIT 2

ICC# 681-6X6-96

877-ICC-8788

8
7

6.00" +/- 1.00"

7-
I
C
C

-8
78
8

877-ICC-8788

8
7
7

-I
C
C

-8
7
88

6.00" +/- 1.00"

CABLE ASS'Y
ICC# 801195

12VAC

XFMR IN PHU

F

B

CABLE

96.00"

CABLE

ICC# 681-6X6-12

12.00"

J2

J1

TO STATION
INTERFACE BOX

VCC

SECONDARY PHU POWER
SUPPLY BOARD
ICC 810680#-1

877-ICC-8788

8
7
7

-IC

C

-
8
7
8
8

877-ICC-8788

87
7

-
IC
C

-
8
7
8
8

6.00" +/- 1.00"

J4

KEYBD
FRONT

J3

KEYBD
BACK

6.00" +/- 1.00"

CABLE ASS'Y
ICC# 801195

BLACK

CABLE

ICC# 681-6X6-12

12.00"

1:1 CONNECTOR

WARMER
CONTROL

WARMER
ADAPTER

ICC# 810004

BLACK

12VAC

XFMR IN PHU

B

J2

J1

CABLE

F

ICC# 681-6X6-12

12.00"

J4

KEYBD
FRONT

J3

TO STATION

KEYBD

INTERFACE BOX

BACK

VCC

SECONDARY PHU POWER
SUPPLY BOARD
ICC 810680#-1

PRODUCT HOLDING UNIT 3

Part Number MHCFA_Service Manual 03/16 31

ICC Timer Bar and Kitchen Minder Section 7

CABLE TO KITCHEN MINDER

PRODUCT HOLDING UNIT 2

BACK ICC P/N 980240#

FRONT ICC P/N 980240# FRONT ICC P/N 980240#

1:1 CONNECTOR

ICC# 681-6X6-12

CABLE

12.00"

CABLE

96.00"

ICC# 681-6X6-96

CABLE

12.00"

ICC# 681-6X6-12

WARMER
ADAPTER
ICC# 810004

F

B

WARMER
CONTROL

PRODUCT HOLDING UNIT 3

BACK ICC P/N 980240#

FRONT ICC P/N 980240#

1:1 CONNECTOR

CABLE

12.00"

ICC# 681-6X6-12

WARMER
ADAPTER
ICC# 810004

F

B

WARMER
CONTROL

MHCFA24 Timer Bar Diagram

NOTE: “Warmer Control” on diagram is the I/O board.

BACK ICC P/N 980240#

FRONT ICC P/N 980240#

CABLE ASS'Y

BLACK

BLACK

ICC# 801195

12VAC

XFMR IN PHU

PRODUCT HOLDING UNIT 1

6.00" +/- 1.00"

8
7
7

­IC
C

-8
78
8

8
7
7

-I
C
C

­8
7
8
8

6.00" +/- 1.00"

WARMER
CONTROL

CABLE

ICC# 681-6X6-12

12.00"

J5

WMR 1

WMR 2

J4

J2

J1

STATION INTERFACE CON TROL BOARD

ICC # 810195-80#

WMR 3

J3

CABLE

ICC# 681-8X8-12

12.00"

F

B

WARMER
ADAPTER

ICC# 810004

CAT 5

1:1 CONNECTOR

CABLE

ICC# 681-6X6-96

96.00"

1:1 CONNECTOR

1:1 CONNECTOR

BACK ICC P/N 980240#

FRONT ICC P/N 980240#

8
7
7

­I
C
C

­8
7
8
8

8
7
7

-I
C
C

­8
7
8
8

6.00" +/- 1.00"

6.00" +/- 1.00"

1:1 CONNECTOR

1:1 CONNECTOR

WARMER

CABLE

ICC# 681-6X6-12

12.00"

CABLE TO KITCHEN MINDER

CONTROL

WARMER
ADAPTER

ICC# 810004

B

F

PRODUCT HOLDING UNIT 2

CABLE

ICC# 681-6X6-96

96.00"

CABLE

ICC# 681-6X6-12

12.00"

32 Part Number MHCFA_Service Manual 03/16

Section 7 ICC Timer Bar and Kitchen Minder

Continued MHCFA24 Timer Bar Diagram

NOTE: “Warmer Control” on diagram is the I/O board.

1:1 CONNECTOR

WARMER
CONTROL

CABLE

ICC# 681-6X6-12

12.00"

BACK ICC P/N 980240#

FRONT ICC P/N 980240#

B

WARMER
ADAPTER

ICC# 810004

F

1:1 CONNECTOR

CABLE

ICC# 681-6X6-12

12.00"

PRODUCT HOLDING UNIT 3

8

6.00" +/- 1.00"

77

­I
C
C

­8
7
8
8

8
7
7

­IC
C

­87
8
8

Part Number MHCFA_Service Manual 03/16 33

ICC Timer Bar and Kitchen Minder Section 7

MHCFA34 Timer Bar Diagram

NOTE: “Warmer Control” on diagram is the I/O board.

FRONT ICC P/N 980105-1X4#

FRONT ICC P/N 980105-2X4#

CABLE ASS'Y

12VAC

XFMR IN PHU

ICC# 801195

BLACK

BLACK

PRODUCT HOLDING UNIT 1

FRONT ICC P/N 980105-1X4#

FRONT ICC P/N 980105-2X4#

WARMER
CONTROL

J2

J1

PHU II HUB CONTROL BOARD
A/N WITH TEMP, 3H
ICC # 810195-83#

WMR 1

J5

J4

WMR 2

J3

CABLE NOT TO EXCEED

60.00" IN LENGTH

WMR 3

6.00" +/- 1.00"

8
77

­I
CC

-8
7
8
8

87

6.00" +/- 1.00"

7­I
C
C

-8
78
8

CABLE

ICC# 681-6X6-12

12.00"

CABLE

ICC# 681-8X8-12

12.00"

8
77

­I
CC

-8
7
8
8

87
7­I
C
C

-8
78
8

F

6.00" +/- 1.00"

6.00" +/- 1.00"

B

WARMER
ADAPTER

ICC# 810004

6.00" +/- 1.00"

6.00" +/- 1.00"

MODIFIED TEE

B

F

PIN 1 TO PIN 1

ICC# 802008

ICC# 681-6X6-12

CABLE NOT TO EXCEED

60.00" IN LENGTH

CABLE

ICC# 681-6X6-12

12.00"

CABLE

12.00"

6.00" +/- 1.00"

6.00" +/- 1.00"

877-ICC-8788

877-ICC-8788

BACK ICC P/N 980105-2X4#

1:1 CONNECTOR

CABLE

ICC# 681-6X6-96

96.00"

CAT 5

1:1 CONNECTOR

CABLE TO KITCHEN MINDER

BACK ICC P/N 980105-1X4#

877-ICC-8788

BACK ICC P/N 980105-1X4#

877-ICC-8788

BACK ICC P/N 980105-2X4#

TEE CONNECTOR

PIN 1 TO PIN 1

ICC# 633101

CABLE

ICC# 681-6X6-12

12.00"

CABLE NOT TO EXCEED

60.00" IN LENGTH

WARMER
CONTROL

1:1 CONNECTOR

CABLE

ICC# 681-6X6-12

12.00"

BLACK

WARMER
ADAPTER
ICC# 810004

TEE CONNECTOR

PIN 1 TO PIN 1
ICC# 633101

CABLE

ICC# 681-6X6-12

12.00"

CABLE ASS'Y

12VAC

XFMR IN PHU

ICC# 801195

CABLE

ICC# 681-6X6-12

12.00"

J1

J2

TO STATION
INTERFACE BOX

VCC

SECONDARY PHU POWER SUPPLY BOARD
ICC 810680#-1

BLACK

F

B

CABLE NOT TO EXCEED

60.00" IN LENGTH

J4

KEYBD
FRONT

J3

KEYBD
BACK

PRODUCT HOLDING UNIT 2

34 Part Number MHCFA_Service Manual 03/16

Section 7 ICC Timer Bar and Kitchen Minder

BLACK

BLACK

BACK

FRONT

BACK

1:1 CONNECTOR

ICC# 681-6X6-12

CABLE

12.00"

WARMER
CONTROL

F

B

WARMER
ADAPTER

ICC# 810004

ALPHA/NUMERIC 2 WIDE KEYBOARD ICC P/N 980105-2X2#-T

ALPHA/NUMERIC 2 WIDE KEYBOARD ICC P/N 980105-2X2#

ALPHA/NUMERIC 2 WIDE KEYBOARD ICC P/N 980105-2X2#-T

ALPHA/NUMERIC 2 WIDE KEYBOARD ICC P/N 980105-2X2#

MHCFA42 Timer Bar Diagram

NOTE: “Warmer Control” on diagram is the I/O board.

BACK

ALPHA/NUMERIC 2 WIDE KEYBOARD ICC P/N 980105-2X2#-T

ALPHA/NUMERIC 2 WIDE KEYBOARD ICC P/N 980105-2X2#

6.00" +/- 1.00"

8
7
7

6.00" +/- 1.00"

­I
C
C

-8
7
8
8

UNMODIFIED TEE

PIN 1 TO PIN 1

ICC# 633101

CABLE

ICC# 681-6X6-12

12.00"

ALPHA/NUMERIC 2 WIDE KEYBOARD ICC P/N 980105-2X2#-T

ALPHA/NUMERIC 2 WIDE KEYBOARD ICC P/N 980105-2X2#

6.00" +/- 1.00"

877-ICC-8788 877-ICC-8788

6.00" +/- 1.00"

UNMODIFIED TEE

PIN 1 TO PIN 1

ICC# 633101

CABLE

ICC# 681-6X6-12

12.00"

FRONT

ALPHA/NUMERIC 2 WIDE KEYBOARD ICC P/N 980105-2X2#-T

ALPHA/NUMERIC 2 WIDE KEYBOARD ICC P/N 980105-2X2#

CABLE ASS'Y

BLACK

ICC# 801195

BLACK

12VAC

XFMR IN PHU

PRODUCT HOLDING UNIT 1

8
7
7

­I
C
C

­8
7
8
8

6.00" +/- 1.00"

6.00" +/- 1.00"

J1

J2

PHU II HUB CONTROL BOARD

A/N WITH TEMP, 2H
ICC # 810195-80#

UNMODIFIED TEE

WARMER
CONTROL

WMR 2

PIN 1 TO PIN 1

ICC# 633101

WMR 1

J5

J4

WMR 3

J3

CABLE CAT 5

ICC# 681-8X8-12

12.00"

CABLE

ICC# 681-6X6-12

12.00"

ICC# 681-6X6-12

CABLE NOT TO EXCEED

60.00" IN LENGTH

ALPHA/NUMERIC 2 WIDE KEYBOARD ICC P/N 980105-2X2#-T

ALPHA/NUMERIC 2 WIDE KEYBOARD ICC P/N 980105-2X2#

CABLE

12.00"

CABLE

ICC# 681-6X6-12

12.00"

ICC# 681-6X6-12

BACK

B

F

WARMER

ADAPTER

ICC# 810004

1:1 CONNECTOR

CABLE

12.00"

1:1 CONNECTOR

1:1 CONNECTOR

CAT 5

CABLE

ICC# 681-6X6-96

96.00"

ALPHA/NUMERIC 2 WIDE KEYBOARD ICC P/N 980105-2X2#-T

ALPHA/NUMERIC 2 WIDE KEYBOARD ICC P/N 980105-2X2#

WARMER
CONTROL

1:1 CONNECTOR

CABLE

ICC# 681-6X6-12

12.00"

ICC# 810004

CABLE TO KITCHEN MINDER

6.00" +/- 1.00"

UNMODIFIED TEE

8
7

6.00" +/- 1.00"

7

­IC
C

­8
7
8
8

PIN 1 TO PIN 1

ICC# 633101

FRONT

CABLE ASS'Y
ICC# 801195

BLACK

BLACK

12VAC

XFMR IN PHU

CABLE

ICC# 681-6X6-12

12.00"

WARMER
ADAPTER

B

F

PRODUCT HOLDING UNIT 2

CABLE

ICC# 681-6X6-96

96.00"

CABLE

ICC# 681-6X6-12

12.00"

6.00" +/- 1.00"

6.00" +/- 1.00"

J1

J2

TO STATION
INTERFACE BOX

VCC

SECONDARY PHU POWER SUPPLY BOARD
ICC 810680#-1

UNMODIFIED TEE

PIN 1 TO PIN 1

ICC# 633101

J4

KEYBD
FRONT

J3

KEYBD
BACK

CABLE

ICC# 681-6X6-12

12.00"

FRONT

ALPHA/NUMERIC 2 WIDE KEYBOARD ICC P/N 980105-2X2#-T

6.00" +/- 1.00"

8
7

6.00" +/- 1.00"

7

­IC
C

-8
7
8
8

UNMODIFIED TEE

PIN 1 TO PIN 1

ICC# 633101

CABLE

ICC# 681-6X6-12

12.00"

ALPHA/NUMERIC 2 WIDE KEYBOARD ICC P/N 980105-2X2#

1:1 CONNECTOR

WARMER
CONTROL

CABLE

ICC# 681-6X6-12

12.00"

WARMER
ADAPTER

ICC# 810004

CABLE ASS'Y
ICC# 801195

BLACK

BLACK

12VAC

XFMR IN PHU

B

F

CABLE

ICC# 681-6X6-12

12.00"

J1

PRODUCT HOLDING UNIT 3

J4

KEYBD
FRONT

J3

J2

TO STATION

KEYBD

INTERFACE BOX

BACK

VCC

SECONDARY PHU POWER SUPPLY BOARD
ICC 810680#-1

Part Number MHCFA_Service Manual 03/16 35

ICC Timer Bar and Kitchen Minder Section 7

THIS PAGE INTENTIONALLY LEFT BLANK

36 Part Number MHCFA_Service Manual 03/16

Section 8

Charts

Zone Diagrams & Heating Element Specifications

Key Air Heater Pad Heater

MHCFA22 & MHCFA22EX

Location Heater Model Description Resistance Part Number

MHCFA22 700W, 120V 18.9Ω +/- 5% 2195351

All Zones Air Heater

All Zones Pad Heater

There are two bins per zone.

MHCFA23 & MHCFA23EX

Location Part Description Resistance Part Number

Zones 2 & 4 Air Heater, 350W, 230V 143Ω +/- 5% 2195350

Zones 2 & 4 Pad Heater, 100W, 230V 529Ω +/- 10% 2198599

MHCFA22EX 700W, 230V 18.9Ω +/- 5% 2195352

MHCFA22 330W, 120V 43.33Ω +/- 10% 2198616

MHCFA22EX 330W, 230V 43.33Ω +/- 10% 2198629

MHCFA24, MHCFA24EX & MHCFA42EX

MHCFA34 & MHCFA34EX

Location Heater Model Description Resistance Part Number

All Zones Air Heater

Zones 1 & 3 Air Heater, 700W, 230V 71.8Ω +/- 5% 2195352

Zones 1 & 3 Pad Heater, 200W, 230V 265.5Ω +/- 10% 2198598

In zones 1 & 3 there are two bins per zone.
In zones 2 & 4 there is one bin per zone.

Location Heater Model Description Resistance

MHCFA24 700W, 230V 71.8Ω +/- 5% 2195352

All Zones

All Zones Pad

Air

Heater

Heater

MHCFA24EX,

MHCFA42EX

All Models 200W, 230V 265.5Ω +/- 10% 2198598

450W, 230V 111.6Ω +/- 5% 2195358

There are two bins per zone.

MHCFA34 450W, 230V 111.6Ω +/- 5% 2195358

MHCFA34EX 350W, 230V 143.6Ω +/- 5% 2195350

Part

Number

MHCFA34 200W, 230V 265.5Ω +/- 10% 2198598

All Zones Pad Heater

MHCFA34EX 100W, 230V 529Ω +/- 10% 2198628

There are two bins per zone.

Part Number MHCFA_Service Manual 03/16 37

Charts Section 8

System Layout

System Layout
Only 2 Secondary I/O Boards Shown

BD Board

RJ12 Cable

I/O Board (Secondary 1)

I/O Board (Secondary 2)

RJ45 Cable

RJ45 Cable

I/O Board (Primary)

SW1 and J5 settings together define the system address.

Note how small J5 Jumper is compared to a dime.

Caution

,

Ensure SW1 dip switches and J5 jumper match the old

I/O Board upon replacement.

When the jumper is in the wrong position, zones will not

display when checking temperature.

12 Pin LED Connector

8 Pin Keypad Connector

J5 Setting SW1 Setting

CI Membrane Switch

SW1

Setting

ON

ON

ON

+

1 2 3

1 2 3

1 2 3

0B

0A

J5

Setting

=

System Address

0A [PRIMARY]0A

0B [SECONDARY]

SECONDARY]

1A [

38 Part Number MHCFA_Service Manual 03/16

Section 8 Charts

I/O Board

Caution

,

I/O Board must be loaded with software. Starting March 2016, factory will mark the backside with an orange
sticker when software is loaded.

Part Number MHCFA_Service Manual 03/16 39

Charts Section 8

I/O Board Connections

MHCFA22 & MHCFA22EX

Primary 0A I/O Board

Zone

2 Air J22 J3

1 Air J18 J1

Heater

Type

Pad J24 J4

Pad J20 J2

MCFA23, MHCFA23EX, MHCFA24 & MHCFA24EX

Heater

Connect to:

Probe

Connect to:

Primary 0A I/O Board

Zone

4 Air J22 J3

2 Air J18 J1

Heater

Type

Pad J24 J4

Pad J20 J2

Heater

Connect to:

Connect to:

Probe

Secondary 0B I/O Board

Zone

3 Air J22 J3

1 Air J18 J1

Heater

Type

Pad J24 J4

Pad J20 J2

Heater

Connect to:

MHCFA34 & MHCFA34EX

Secondary 0B I/O Board

Zone

3 Air J22 J3

1 Air J18 J1

Heater

Type

Pad J24 J4

Pad J20 J2

Heater

Connect to:

Probe

Connect to:

Probe

Connect to:

Secondary 1A I/O Board

Zone

6 Air J22 J3

5 Air J18 J1

4 Air J22 J3

2 Air J18 J1

Heater

Type

Pad J24 J4

Pad J20 J2

Primary 0A I/O Board

Pad J24 J4

Pad J20 J2

Heater

Connect to:

Connect to:

Probe

40 Part Number MHCFA_Service Manual 03/16

Section 8 Charts

MHCFA42EX

Secondary 0B I/O Board

Zone

3 Air J22 J3

1 Air J18 J1

Zone

4 Air J22 J3

2 Air J18 J1

Heater

Type

Pad J24 J4

Pad J20 J2

Primary 0A I/O Board

Heater

Type

Pad J24 J4

Pad J20 J2

Heater

Connect to:

Heater

Connect to:

Probe

Connect to:

Probe

Connect to:

Part Number MHCFA_Service Manual 03/16 41

Charts Section 8

THIS PAGE INTENTIONALLY LEFT BLANK

42 Part Number MHCFA_Service Manual 03/16

MHCFA22 - Domestic 2x2

DISPLAY B0ARD

Section 9

Wiring Diagrams

J3

J1

SW1

J6

J5

J4

I/O 0A B0ARD - ZONES 1 AND 2

USB ADAPTER CABLE TO PANEL

MEMBRANE SWITCH,12 PIN RIBBON

MEMBRANE SWITCH,8 PIN RIBBON

PN: 2195357

J2

PN:2187007

I/O 0A,J10,6PIN

J15

J14

J8

J7

J18

J17

J2 J3 J4

J1

J19

J6

J20

SW1

J5

J14

J21

YL,TC,AIR,ZONE 1

BR,TC,PAD,ZONE 1

YL,TC,AIR,ZONE 2

BR,TC,PAD,ZONE 2

J16

J11
J12

J22

J23

J10

J24

PN: 2187010

RD (+) 12VDC, TERM BLOCK

BL (-) 12VDC, TERM BLOCK

DISP BRD, J6, 6PIN

PN:2186998

SW1

TO ICC WARMER ADAPTER

PN: 2187057

J5

J17 J18

J19

J20

J21

J22

J23

J24

BR,AC L,RH TERM BLOCK

PN: 2187009

BR,PAD,ZONE 2,RH SIDE,TOP

BR,AIR, ZONE 2,RH SIDE,TOP

BR,PAD,ZONE 1,RH SIDE,BOT

BR,AIR,ZONE 1,RH SIDE,BOT

Part Number MHCFA_Service Manual 03/16 43

Wiring Diagrams Section 9

12VDC POWER SUPPLY

MHCFA22 - Domestic 2x2

GN, TO #10 GROUND STUD

BU,AC N,RH TERM BLOCK

BR,AC L,RH TERM BLOCK

PN: 2187013

POWER SWITCH

PN:2187019

RH - TOP ZONE - ZONE 2

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

YL,I/O 0A,J3(TC,AIR,TOP)

BR,I/O 0A,J22(AIR,TOP)

BU,AC N,LH TERM BLOCK

BR,I/O 0A,J4(TC,PAD,TOP)

BR,I/O 0A,J24(PAD,TOP)

BU,AC N,LH TERM BLOCK

CN2 - 12VDC OUTPUT

CN1 - 100 TO 277VAC INPUT

BL,AC L,INCOMING POWER

WH,AC N,INCOMING POWER

BU,AC N,TO TERM BLOCK

BR,AC L,TO TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

RD(+)12VDC,RH TERM BLOCK

RD(+)12VDC,RH TERM BLOCK

PN: 2187012

GN, TO #10 GROUND STUD

RH - BOTTOM ZONE - ZONE 1

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

YL,I/O 0A,J1(TC,AIR,BTM)

BR,I/O 0A,J18(AIR,BTM)

BU,AC N,TERM BLOCK

BR,I/O 0A,J2(TC,PAD,BTM)

BR,I/O 0A,J20(PAD,BTM)

BU,AC N,TERM BLOCK

RD(+)12VDC FROM PS

RD(+)12VDC TO KM

RD(+)12VDC FROM PS

RD(+)12VDC TO FAN 1

RD(+)12VDC TO FAN 2

RD(+)12VDC TO RH I/O 0A

BL(-)12VDC FROM PS

BL(-)12VDC TO KM

BL(-)12VDC FROM PS

BL(-)12VDC TO FAN 1

BL(-)12VDC TO FAN 2

BL(-)12VDC TO I/O 0A

BU,AC N,PAD 1

BU,AC N,PAD 2

BU,AC N,JUMPER

RH - TERMINAL BLOCK

BU,AC N,SWITCH

BU,AC N,AIR 1

BU,AC N,AIR 2

BU,AC N,JUMPER

BU,AC N,TO PS

BU,AC N,JUMPER

BR,AC L,FROM SWITCH

BR,AC L,TO PS

BR,AC L,TO I/O 0A,J17,19,21,23

44 Part Number MHCFA_Service Manual 03/16

Section 9 Wiring Diagrams

MHCFA22EX - Export 2x2

EMI FILTER

PN:2187019

POWER SWITCH

PN:2186989

AND RECEPTACLE

PN:2187019

USB ADAPTER CABLE TO PANEL

MEMBRANE SWITCH,12 PIN RIBBON

I/O 0A B0ARD - ZONES 1 AND 2

MEMBRANE SWITCH,8 PIN RIBBON

PN: 2195357

TO ICC WARMER ADAPTER

PN: 2187057

PN:2187007

BU,AC N,TO TERM BLOCK

BR,AC L,TO TERM BLOCK

J1

J15

J14

J8

J7

J18

J17

J17 J18

J2 J3 J4

J6

J19

J19

J20

J20

SW1

J5

J14

J21

J21

GN, TO #10 GROUND STUD

YL,TC,AIR,ZONE 1

BR,TC,PAD,ZONE 1

YL,TC,AIR,ZONE 2

BR,TC,PAD,ZONE 2

J16

J10

J11

J12

J22

J23

J23

J22

J24

J24

PN: 2187010

RD (+) 12VDC, TERM BLOCK

BL (-) 12VDC, TERM BLOCK

DISP BRD, J6, 6PIN

PN:2186998

SW1

J5

PN: 2187009

BR,AC L,RH TERM BLOCK

BR,PAD,ZONE 2,RH SIDE,TOP

BR,AIR, ZONE 2,RH SIDE,TOP

BR,PAD,ZONE 1,RH SIDE,BOT

BR,AIR,ZONE 1,RH SIDE,BOT

Part Number MHCFA_Service Manual 03/16 45

J5

SW1

J19

J20

J21

J22

J23

J24

PN: 2187009

J17 J18

PN: 2195357

BR,AIR, ZONE 2,RH SIDE,TOP

BR,PAD,ZONE 2,RH SIDE,TOP

BR,AIR,ZONE 1,RH SIDE,BOT

BR,PAD,ZONE 1,RH SIDE,BOT

BR,AC L,RH TERM BLOCK

PN: 2187057

TO ICC WARMER ADAPTER

Wiring Diagrams Section 9

MHCFA22EX - Export 2x2

12VDC POWER SUPPLY

GN, TO #10 GROUND STUD

BU,AC N,RH TERM BLOCK

BR,AC L,RH TERM BLOCK

CN1 - 100 TO 277VAC INPUT

PN: 2187013

RH - BOTTOM ZONE - ZONE 1

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

YL,I/O 0A,J1(TC,AIR,BTM)

BR,I/O 0A,J18(AIR,BTM)

BU,AC N,TERM BLOCK

BR,I/O 0A,J2(TC,PAD,BTM)

BR,I/O 0A,J20(PAD,BTM)

BU,AC N,TERM BLOCK

CN2 - 12VDC OUTPUT

BL(-)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

RD(+)12VDC,RH TERM BLOCK

RD(+)12VDC,RH TERM BLOCK

PN: 2187012

RH - TOP ZONE - ZONE 2

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

YL,I/O 0A,J3(TC,AIR,TOP)

BR,I/O 0A,J22(AIR,TOP)

BU,AC N,LH TERM BLOCK

BR,I/O 0A,J4(TC,PAD,TOP)

BR,I/O 0A,J24(PAD,TOP)

BU,AC N,LH TERM BLOCK

DISPLAY B0ARD

J3

SW1

J5

J4

J2

J1

J6

I/O 0A,J10,6PIN

RD(+)12VDC FROM PS

RD(+)12VDC TO KM

RD(+)12VDC FROM PS

RD(+)12VDC TO FAN 1

RD(+)12VDC TO FAN 2

RD(+)12VDC TO RH I/O 0A

BL(-)12VDC FROM PS

BL(-)12VDC TO KM

BL(-)12VDC FROM PS

BL(-)12VDC TO FAN 1

BL(-)12VDC TO FAN 2

BL(-)12VDC TO I/O 0A

BU,AC N,PAD 1

BU,AC N,PAD 2

BU,AC N,JUMPER

RH - TERMINAL BLOCK

BU,AC N,SWITCH

BU,AC N,AIR 1

BU,AC N,AIR 2

BU,AC N,JUMPER

BU,AC N,TO PS

BU,AC N,JUMPER

BR,AC L,FROM SWITCH

BR,AC L,TO PS

BR,AC L,TO I/O 0A,J17,19,21,23

46 Part Number MHCFA_Service Manual 03/16

Section 9 Wiring Diagrams

MHCFA23 & MHCFA24 - Domestic 2x3 & 2x4

YL,TC,AIR,ZONE 2

BR,TC,PAD,ZONE 2

YL,TC,AIR,ZONE 4

BR,TC,PAD,ZONE 4

PN: 2187010

PN:2187007

USB ADAPTER CABLE TO PANEL

MEMBRANE SWITCH,12 PIN RIBBON

MEMBRANE SWITCH,8 PIN RIBBON

PN: 2195357

I/O 0A B0ARD - ZONES 2 AND 4

TO ICC WARMER ADAPTER

PN: 2187057

POWER SWITCH

PN: 2187009

BL,AC L,INCOMING POWER

WH,AC N,INCOMING POWER

J15

J14

J8

J7

J18

J17

J17 J18

J1

J19

J2 J3 J4

J6

J20

J19

J20

SW1

J5

J14

J21

J21

J22

J22

J16

J23

J23

J10
J11
J12

J24

J24

BR,PAD,ZONE 4,RH SIDE,TOP

BR,AIR, ZONE 4,RH SIDE,TOP

BR,PAD,ZONE 2,RH SIDE,BOT

BR,AIR,ZONE 2,RH SIDE,BOT

RD (+) 12VDC, TERM BLOCK

BL (-) 12VDC, TERM BLOCK

DISP BRD, J6, 6PIN

PN:2186998

TO I/O 0B, J12, 8PIN

PN:2186997

SW1

J5

BR,AC L,RH TERM BLOCK

PN:2187019

J3

BU,AC N,TO TERM BLOCK

BR,AC L,TO TERM BLOCK

J2

GN, TO #10 GROUND STUD

DISPLAY

J5

J1

B0ARD

J6

I/O 0A,J10,6PIN

SW1

J4

Part Number MHCFA_Service Manual 03/16 47

Wiring Diagrams Section 9

MHCFA23 & MHCFA24 - Domestic 2x3 & 2x4

GN, TO #10 GROUND STUD

BU,AC N,RH TERM BLOCK

BR,AC L,RH TERM BLOCK

12VDC POWER SUPPLY

RD(+)12VDC TO LH SIDE

RD(+)12VDC TO FAN 1

RD(+)12VDC TO FAN 2

RD(+)12VDC TO RH I/O 0A

PN: 2187013

RD(+)12VDC FROM PS

RD(+)12VDC TO KM

RD(+)12VDC FROM PS

CN1 - 100 TO 277VAC INPUT

BL(-)12VDC FROM PS

BL(-)12VDC TO KM

BL(-)12VDC TO LH SIDE

CN2 - 12VDC OUTPUT

BU,AC N,PAD 1

BU,AC N,PAD 2

BU,AC N,TO LH SIDE

BU,AC N,JUMPER

BL(-)12VDC FROM PS

BL(-)12VDC TO FAN 1

BL(-)12VDC TO FAN 2

BL(-)12VDC TO I/O 0A

BL(-)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

RD(+)12VDC,RH TERM BLOCK

RD(+)12VDC,RH TERM BLOCK

PN: 2187012

RH - TERMINAL BLOCK

BU,AC N,SWITCH

BU,AC N,AIR 1

BU,AC N,AIR 2

BU,AC N,JUMPER

BU,AC N,TO PS

BU,AC N,JUMPER

BR,AC L, FROM SWITCH

BR,AC L,TO LH SIDE

BR,AC L,TO PS

BR,AC L,TO I/O 0A,J17,19,21,23

LH - TOP ZONE - ZONE 3

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

YL,I/O 0B,J3(TC,AIR,TOP)

BR,I/O 0B,J22(AIR,TOP)

BU,AC N,LH TERM BLOCK

BR,I/O 0B,J4(TC,PAD,TOP)

BR,I/O 0B,J24(PAD,TOP)

BU,AC N,LH TERM BLOCK

LH - BOTTOM ZONE - ZONE 1

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

YL,I/O 0B,J1(TC,AIR,BTM)

BR,I/O 0B,J18(AIR,BTM)

BU,AC N,TERM BLOCK

BR,I/O 0B,J2(TC,PAD,BTM)

BR,I/O 0B,J20(PAD,BTM)

BU,AC N,TERM BLOCK

RH - TOP ZONE - ZONE 4

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

YL,I/O 0A,J3(TC,AIR,TOP)

BR,I/O 0A,J22(AIR,TOP)

BU,AC N,LH TERM BLOCK

BR,I/O 0A,J4(TC,PAD,TOP)

BR,I/O 0A,J24(PAD,TOP)

BU,AC N,LH TERM BLOCK

RH - BOTTOM ZONE - ZONE 2

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

YL,I/O 0A,J1(TC,AIR,BTM)

BR,I/O 0A,J18(AIR,BTM)

BU,AC N,TERM BLOCK

BR,I/O 0A,J2(TC,PAD,BTM)

BR,I/O 0A,J20(PAD,BTM)

BU,AC N,TERM BLOCK

48 Part Number MHCFA_Service Manual 03/16

Section 9 Wiring Diagrams

MHCFA23 & MHCFA24 - Domestic 2x3 & 2x4

BR,AC L,LH TERM BLOCK

BU,AC N,LH TERM BLOCK

BU,AC N,LH TERM BLOCK

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

I/O 0B B0ARD - ZONES 1 AND 3

J14

J8

J17

J15

J7

J18

J1

J19

J2 J3 J4

J6

J5

J14

J20

PN: 2187011

YL,TC,AIR,ZONE 1
BR,TC,PAD,ZONE 1
YL,TC,AIR,ZONE 3

BR,TC,PAD,ZONE 3

J16

SW1

J10
J11
J12

J22

J21

J23

J24

BR,AC L,RH TERM BLOCK

BU, AC N,RH TERM BLOCK

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

PN: 2187010

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

PN: 2187006

FROM I/O 0A, J11, 8PIN

SW1

PN: 2187009

LH - TERMINAL
BLOCK

RD(+)12VDC FROM RH SIDE

RD(+)12VDC TO FAN 1

RD(+)12VDC TO FAN 2

RD(+)12VDC TO I/O 0B

J17 J18

J20

J19

J21

BU,AC N,PAD 1

BU,AC N,PAD 2

BU,AC N,FROM RH SIDE

BL(-)12VDC FROM RH SIDE

BL(-)12VDC TO FAN 1

BL(-)12VDC TO FAN 2

BL(-)12VDC TO I/O 0B

J22

J23

J24

BR,PAD,ZONE 3,LH SIDE,TOP

BR,AIR,ZONE 3,LH SIDE,TOP

BR,PAD,ZONE 1,LH SIDE,BOT

BR,AIR,ZONE 1,LH SIDE,BOT

J5

BR,AC L,LH TERM BLOCK

BR,AC L,RH SIDE

BR,AC L, TO I/O 0B

J17,19,21,23

BU,AC N,AIR 1

BU,AC N,AIR 2

BU,AC N,FROM RH SIDE

Part Number MHCFA_Service Manual 03/16 49

Wiring Diagrams Section 9

DISPLAY B0ARD

MHCFA23EX & MHCFA24EX - Export 2x3 & 2x4

POWER SWITCH

J3

POWER CORD

J2

BROWN

BLUE

GREEN/YELLOW

BL,AC L,FROM EMI FILTER

BU,AC N,FROM EMI FILTER

PN:2187019

BL,AC L,TO POWER SWITCH

BU,AC N,TO POWER SWITCH

EMI FILTER

BR,AC L,TO EMI FILTER

BU,AC N,TO EMI FILTER

BU,AC N,TO TERM BLOCK

BR,AC L,TO TERM BLOCK

J4

SW1

J5

J1

J6

I/O 0A,J10,6PIN

50 Part Number MHCFA_Service Manual 03/16

I/O 0A B0ARD - ZONES 2 AND 4

SW1

J1

J3

J2

J6

J5

DISPLAY B0ARD

J4

I/O 0A,J10,6PIN

BU,AC N,TO TERM BLOCK

BR,AC L,TO TERM BLOCK

PN:2187019

12VDC POWER SUPPLY

Section 9 Wiring Diagrams

MHCFA23EX & MHCFA24EX - Export 2x3 & 2x4

PN:2187007

USB ADAPTER CABLE TO PANEL

MEMBRANE SWITCH,12 PIN RIBBON

MEMBRANE SWITCH,8 PIN RIBBON

PN: 2195357

YL,TC,AIR,ZONE 2

BR,TC,PAD,ZONE 2

YL,TC,AIR,ZONE 4

BR,TC,PAD,ZONE 4

J2 J3 J4

J1

J14

J8

J17

J15

J7

J18

J19

J6

J5

J14

J20

SW1

J21

J22

J16

J23

J10
J11
J12

J24

PN: 2187010

RD (+) 12VDC, TERM BLOCK

BL (-) 12VDC, TERM BLOCK

DISP BRD, J6, 6PIN

PN:2186998

TO I/O 0B, J12, 8PIN

PN:2186997

SW1

TO ICC WARMER ADAPTER

PN: 2187057

GN, TO #10 GROUND STUD

BU,AC N,RH TERM BLOCK

BR,AC L,RH TERM BLOCK

PN: 2187013

PN: 2187009

CN1 - 100 TO 277VAC INPUT

J17 J18

J20

J19

CN2 - 12VDC OUTPUT

J21

J23

J22

J24

BR,PAD,ZONE 4,RH SIDE,TOP

BR,AIR, ZONE 4,RH SIDE,TOP

BR,PAD,ZONE 2,RH SIDE,BOT

BR,AIR,ZONE 2,RH SIDE,BOT

J5

BR,AC L,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

RD(+)12VDC,RH TERM BLOCK

RD(+)12VDC,RH TERM BLOCK

PN: 2187012

Part Number MHCFA_Service Manual 03/16 51

Wiring Diagrams Section 9

MHCFA23EX & MHCFA24EX - Export 2x3 & 2x4

RD(+)12VDC FROM PS

RD(+)12VDC TO KM

RD(+)12VDC TO LH SIDE

RD(+)12VDC FROM PS

RD(+)12VDC TO FAN 1

RD(+)12VDC TO FAN 2

RD(+)12VDC TO RH I/O 0A

LH - TOP ZONE - ZONE 3

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

YL,I/O 0B,J3(TC,AIR,TOP)

BR,I/O 0B,J22(AIR,TOP)

BU,AC N,LH TERM BLOCK

BR,I/O 0B,J4(TC,PAD,TOP)

BR,I/O 0B,J24(PAD,TOP)

BU,AC N,LH TERM BLOCK

BL(-)12VDC FROM PS

BL(-)12VDC TO KM

BL(-)12VDC TO LH SIDE

BL(-)12VDC FROM PS

BL(-)12VDC TO FAN 1

BL(-)12VDC TO FAN 2

BL(-)12VDC TO I/O 0A

BU,AC N,PAD 1

BU,AC N,PAD 2

BU,AC N,TO LH SIDE

BU,AC N,JUMPER

RH - TERMINAL BLOCK

BU,AC N,SWITCH

BU,AC N,AIR 1

BU,AC N,AIR 2

BU,AC N,JUMPER

RH - TOP ZONE - ZONE 4

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

YL,I/O 0A,J3(TC,AIR,TOP)

BR,I/O 0A,J22(AIR,TOP)

BU,AC N,LH TERM BLOCK

BR,I/O 0A,J4(TC,PAD,TOP)

BR,I/O 0A,J24(PAD,TOP)

BU,AC N,LH TERM BLOCK

BU,AC N,TO PS

BU,AC N,JUMPER

BR,AC L, FROM SWITCH

BR,AC L,TO LH SIDE

BR,AC L,TO PS

BR,AC L,TO I/O 0A,J17,19,21,23

LH - BOTTOM ZONE - ZONE 1

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

YL,I/O 0B,J1(TC,AIR,BTM)

BR,I/O 0B,J18(AIR,BTM)

BU,AC N,TERM BLOCK

BR,I/O 0B,J2(TC,PAD,BTM)

BR,I/O 0B,J20(PAD,BTM)

BU,AC N,TERM BLOCK

BR,AC L,LH TERM BLOCK

BU,AC N,LH TERM BLOCK

BU,AC N,LH TERM BLOCK

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

PN: 2187011

RH - BOTTOM ZONE - ZONE 2

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

YL,I/O 0A,J1(TC,AIR,BTM)

BR,I/O 0A,J18(AIR,BTM)

BU,AC N,TERM BLOCK

BR,I/O 0A,J2(TC,PAD,BTM)

BR,I/O 0A,J20(PAD,BTM)

BU,AC N,TERM BLOCK

BR,AC L,RH TERM BLOCK

BU, AC N,RH TERM BLOCK

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

52 Part Number MHCFA_Service Manual 03/16

Section 9 Wiring Diagrams

MHCFA23EX & MHCFA24EX - Export 2x3 & 2x4

YL,TC,AIR,ZONE 1
BR,TC,PAD,ZONE 1
YL,TC,AIR,ZONE 3

BR,TC,PAD,ZONE 3

PN: 2187010

I/O 0B B0ARD - ZONES 1 AND 3

PN: 2187009

J15

J14

J8

J7

J18

J17

J17 J18

J1

J2 J3 J4

J19

J19

J6

J20

SW1

J5

J14

J20

J21

J21

J22

J22

J16

J23

J23

J10

J11

J12

J24

J24

BR,PAD,ZONE 3,LH SIDE,TOP

BR,AIR,ZONE 3,LH SIDE,TOP

BR,PAD,ZONE 1,LH SIDE,BOT

BR,AIR,ZONE 1,LH SIDE,BOT

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

PN: 2187006

FROM I/O 0A, J11, 8PIN

SW1

J5

BR,AC L,LH TERM BLOCK

LH - TERMINAL BLOCK

RD(+)12VDC FROM RH SIDE

RD(+)12VDC TO FAN 1

RD(+)12VDC TO FAN 2

RD(+)12VDC TO I/O 0B

Part Number MHCFA_Service Manual 03/16 53

BU,AC N,PAD 1

BU,AC N,PAD 2

BU,AC N,FROM RH SIDE

BL(-)12VDC FROM RH SIDE

BL(-)12VDC TO FAN 1

BL(-)12VDC TO FAN 2

BL(-)12VDC TO I/O 0B

BU,AC N,AIR 1

BU,AC N,AIR 2

BU,AC N,FROM RH SIDE

BR,AC L,FROM RH SIDE

BR,AC L, TO I/O 0B

J17,19,21,23

Wiring Diagrams Section 9

I/O 1A B0ARD - ZONES 5 AND 6

MHCFA34 - Domestic 3x4

YL,TC,AIR,ZONE 5

BR,TC,PAD,ZONE 5

YL,TC,AIR,ZONE 6

BR,TC,PAD,ZONE 6

PN: 2187010

PN: 2187009

J1

J15

J14

J8

J7

J18

J17

J17 J18

J2 J3 J4

J6

J19

J19

J20

SW1

J5

J14

J20

J21

J21

J22

J22

J16

J23

J23

J10
J11
J12

J24

J24

BR,PAD,ZONE 6,RH SIDE,TOP

BR,AIR, ZONE 6,RH SIDE,TOP

BR,PAD,ZONE 5,LH SIDE,TOP

BR,AIR,ZONE 5,LH SIDE,TOP

RD (+) 12VDC, TERM BLOCK

BL (-) 12VDC, TERM BLOCK

PN: 2187006

FROM 0A I/O, J11, 8PIN

SW1

J5

BR,AC L,RH TERM BLOCK

54 Part Number MHCFA_Service Manual 03/16

Section 9 Wiring Diagrams

I/O 1A B0ARD - ZONES 5 AND 6

FROM 0A I/O, J11, 8PIN

BR,TC,PAD,ZONE 5

YL,TC,AIR,ZONE 6

YL,TC,AIR,ZONE 5

BR,TC,PAD,ZONE 6

J24

J10

J12

J11

J16

J2 J3 J4

J14

J5

SW1

J6

J1

J15

J14

J8

J7

J19

J20

J21

J22

J23

J24

J19

J20

J21

J22

J23

J17

J18

J17 J18

RD (+) 12VDC, TERM BLOCK

BL (-) 12VDC, TERM BLOCK

BR,AC L,RH TERM BLOCK

PN: 2187009

BR,PAD,ZONE 6,RH SIDE,TOP

BR,AIR, ZONE 6,RH SIDE,TOP

BR,PAD,ZONE 5,LH SIDE,TOP

BR,AIR,ZONE 5,LH SIDE,TOP

SW1

PN: 2187010

PN: 2187006

I/O 0A B0ARD - ZONES 2 AND 4

J5

MHCFA34 - Domestic 3x4

USB ADAPTER CABLE TO PANEL

MEMBRANE SWITCH,12 PIN RIBBON

MEMBRANE SWITCH,8 PIN RIBBON

PN:2187007

PN: 2195357

TO ICC WARMER ADAPTER

PN: 2187057

PN: 2187009

YL,TC,AIR,ZONE 2

BR,TC,PAD,ZONE 2

YL,TC,AIR,ZONE 4

BR,TC,PAD,ZONE 4

J2 J3 J4

J1

J15

J6

J14

J8

J7

J18

J17

J17 J18

SW1

J5

J14

J21

J20

J19

J20

J19

J21

J22

J22

J16

J23

J23

J10

J11

J12

J24

J24

BR,PAD,ZONE 4,RH SIDE,MID

BR,AIR, ZONE 4,RH SIDE,MID

BR,PAD,ZONE 2,RH SIDE,BOT

BR,AIR,ZONE 2,RH SIDE,BOT

PN: 2187010

RD (+) 12VDC, TERM BLOCK

BL (-) 12VDC, TERM BLOCK

PN:2186998

PN:2187006

PN:2186997

BR,AC L,RH TERM BLOCK

DISP BRD, J6, 6PIN

TO I/O 1A, J12, 8PIN

TO I/O 0B, J12, 8PIN

SW1

J5

Part Number MHCFA_Service Manual 03/16 55

Wiring Diagrams Section 9

MHCFA34 - Domestic 3x4

INPUT POWER RELAY

BR, AC L,FROM SWITCH

PN: 2187019

BR,AC L,TO TERM BLOCK SWITCH

GN, TO #10 GROUND STUD

GN, GROUND, FROM PS

RD(+)12VDC FROM PS

RD(+)12VDC TO KM

RD(+)12VDC TO LH SIDE

RD(+)12VDC TO RH I/O 1A

RD(+)12VDC FROM PS

RD(+)12VDC TO FAN 1

RD(+)12VDC TO FAN 2/3

RD(+)12VDC TO RH I/O 0A

BL(-)12VDC FROM PS

BL(-)12VDC TO KM

BL(-)12VDC TO LH SIDE

BL(-)12VDC TO RH I/O 1A

BU, AC N,FROM SWITCH

PN: 2187017

BU, AC N,TO TERM BLOCK

BU, AC N,TO POWER SWITCHBR,AC L,TO TERM POWER SWITCH

BU,AC N,PAD 1

BU,AC N, PAD 2

BU,AC N, PAD 3

BU,AC N,JUMPER

DISPLAY B0ARD

J2

J6

I/O 0A,J10,6PIN

J4

SW1

J3

J1

J5

RH - TERMINAL BLOCK

BR,AC L,FROM RELAY

BR,AC L, TO I/O 1A J17,19,21,23

BR,AC L, TO I/O 0A,J17,19,21,23

BU,AC L,JUMPER

GN, TO #10 GROUND STUD

BU,AC N,RH TERM BLOCK

BR,AC L,RH TERM BLOCK

12VDC POWER SUPPLY

PN: 2187013

BR,AC L,LH TERM BLOCK

BU,AC N,LH TERM BLOCK

BU,AC N,LH TERM BLOCK

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

BL(-)12VDC FROM PS

BL(-)12VDC TO FAN 1

BL(-)12VDC TO FAN 2/3

BL(-)12VDC TO I/O 0A

CN2 - 12VDC OUTPUT

CN1 - 100 TO 277VAC INPUT

PN: 2187011

BU,AC N,AIR 1

BU,AC N,AIR 2

BU,AC N,AIR 3

BU,AC N,JUMPER

PN: 2187012

BU,AC N, FROM RELAY

BU,AC N,TO LH SIDE

BU,AC N,TO PS

BU,AC N,JUMPER

BL(-)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

RD(+)12VDC,RH TERM BLOCK

RD(+)12VDC,RH TERM BLOCK

BR,AC L,RH TERM BLOCK

BU, AC N,RH TERM BLOCK

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

BR,AC L,TO LH SIDE

BR, AC L, TO PS

BU,AC L,JUMPER

56 Part Number MHCFA_Service Manual 03/16

Section 9 Wiring Diagrams

MHCFA34 - Domestic 3x4

MALE TERMINALS ON THIS END

BR,AIR,ZONE 5,LH SIDE

BR,PAD,ZONE 5,LH SIDE

LH - TOP ZONE - ZONE 5

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

YL,I/O 1A,J1(TC,AIR,TOP)

BR,I/O 1A,J18(AIR,TOP)*

BU,AC N,LH TERM BLOCK

BR,I/O 1A,J2(TC,PAD,TOP)

BR,I/O 1A,J20(PAD,TOP)*

BU,AC N,LH TERM BLOCK

*CONNECT AC LINE (BROWN) LEADS

TO PROPER TERMINALS ON HARNESS 2187014

LH - MIDDLE ZONE - ZONE 3

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

YL,I/O 0B,J3(TC,AIR,MID)

BR,I/O 0B,J22(AIR,MID)

BU,AC N,LH TERM BLOCK

BR,I/O 0B,J4(TC,PAD,MID)

BR,I/O 0B,J24(PAD,MID)

BU,AC N,LH TERM BLOCK

FEMALE TERMINALS ON THIS END

BR,AIR,ZONE 5, RH SIDE, J18

BR,PAD, ZONE 5,LH SIZE,J20

PN: 2187014

RH - TOP ZONE - ZONE 6

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

YL,I/O 1A,J2(TC,AIR,TOP)

BR,I/O 1A,J22(AIR,TOP)

BU,AC N,LH TERM BLOCK

BR,I/O 1A,J4(TC,PAD,TOP)

BR,I/O 1A,J24(PAD,TOP)

BU,AC N,LH TERM BLOCK

RH - MIDDLE ZONE - ZONE 4

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

YL,I/O 0A,J3(TC,AIR,MID)

BR,I/O 0A,J22(AIR,MID)

BU,AC N,LH TERM BLOCK

BR,I/O 0A,J4(TC,PAD,MID)

BR,I/O 0A,J24(PAD,MID)

BU,AC N,LH TERM BLOCK

LH - BOTTOM ZONE - ZONE 1

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

YL,I/O 0B,J1(TC,AIR,BTM)

BR,I/O 0B,J18(AIR,BTM)

BU,AC N,TERM BLOCK

BR,I/O 0B,J2(TC,PAD,BTM)

BR,I/O 0B,J20(PAD,BTM)

BU,AC N,TERM BLOCK

POWER SWITCH

PN: 2187017

RH - BOTTOM ZONE - ZONE 2

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

YL,I/O 0A,J1(TC,AIR,BTM)

BR,I/O 0A,J18(AIR,BTM)

BU,AC N,TERM BLOCK

BR,I/O 0A,J2(TC,PAD,BTM)

BR,I/O 0A,J20(PAD,BTM)

BU,AC N,TERM BLOCK

BL, AC L,FROM RELAY

BU, AC N,FROM RELAY

BU, AC N,TO RELAY

PN:2187019

BR, AC L,TO RELAY

Part Number MHCFA_Service Manual 03/16 57

Wiring Diagrams Section 9

MHCFA34 - Domestic 3x4

I/O 0B B0ARD - ZONES 1 AND 3

YL,TC,AIR,ZONE 1

BR,TC,PAD,ZONE 1

YL,TC,AIR,ZONE 3

BR,TC,PAD,ZONE 3

PN: 2187010

PN: 2187009

J14

J8

J17

J15

J7

J18

J1

J4J3J2

J16

J6

SW1

J10

J11

J19

J5

J14

J20

J21

J22

J12

J23

J24

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

PN: 2187006

FROM I/O 0A, J11, 8PIN

SW1

J20

J19

J18J17

J21

J22

J23

J24

BR,AC L,LH TERM BLOCK

BR,PAD,ZONE 3,LH SIDE,MID

BR,AIR,ZONE 3,LH SIDE,MID

BR,PAD,ZONE 1,LH SIDE,BOT

BR,AIR,ZONE 1,LH SIDE,BOT

J5

LH - TERMINAL BLOCK

BU,AC N,PAD 1

BU,AC N, PAD 2

BU,AC N, PAD 3

BU,AC N,FROM RH SIDE

RD(+)12VDC FROM RH SIDE

RD(+)12VDC TO FAN 1

RD(+)12VDC TO FAN 2/3

RD(+)12VDC TO I/O 0B

BL(-)12VDC FROM RH SIDE

BL(-)12VDC TO FAN 1

BL(-)12VDC TO FAN 2/3

BL(-)12VDC TO I/O 0B

BU,AC N,AIR 1

BU,AC N,AIR 2

BU,AC N,AIR 3

BU,AC N,FROM RH SIDE

58 Part Number MHCFA_Service Manual 03/16

BR,AC L,FROM RH SIDE

BR,AC L, TO I/O 0B,

J17,19,21,23

Section 9 Wiring Diagrams

MHCFA34EX - Export 3x4

I/O 1A B0ARD - ZONES 5 AND 6

YL,TC,AIR,ZONE 5

BR,TC,PAD,ZONE 5

YL,TC,AIR,ZONE 6

BR,TC,PAD,ZONE 6

PN: 2187010

PN: 2187009

J1

J15

J14

J8

J7

J18

J17

J17 J18

J2 J3 J4

J6

J20

J19

J19

SW1

J5

J14

J20

J21

J21

J22

J22

J16

J23

J23

J10

J11

J12

J24

J24

BR,PAD,ZONE 6,RH SIDE,TOP

BR,AIR, ZONE 6,RH SIDE,TOP

BR,PAD,ZONE 5,LH SIDE,TOP

BR,AIR,ZONE 5,LH SIDE,TOP

RD (+) 12VDC, TERM BLOCK

BL (-) 12VDC, TERM BLOCK

PN: 2187006

FROM 0A I/O, J11, 8PIN

SW1

J5

BR,AC L,RH TERM BLOCK

Part Number MHCFA_Service Manual 03/16 59

FROM 0A I/O, J11, 8PIN

J24

J12

J14

J5

J8

J7

J19

J20

J21

J22

J23

J24

J19

J20

J21

J22

J23

J17

J18

J17 J18

BR,AC L,RH TERM BLOCK

PN: 2187009

BR,PAD,ZONE 6,RH SIDE,TOP

BR,AIR, ZONE 6,RH SIDE,TOP

BR,PAD,ZONE 5,LH SIDE,TOP

BR,AIR,ZONE 5,LH SIDE,TOP

SW1

J5

Wiring Diagrams Section 9

MHCFA34EX - Export 3x4

I/O 0A B0ARD - ZONES 2 AND 4

USB ADAPTER CABLE TO PANEL

MEMBRANE SWITCH,12 PIN RIBBON

MEMBRANE SWITCH,8 PIN RIBBON

PN: 2195357

PN:2187007

J14

J8

J17

J2 J3 J4

J1

J15

J6

SW1

J5

J19

J14

J20

J7

J18

YL,TC,AIR,ZONE 2

BR,TC,PAD,ZONE 2

YL,TC,AIR,ZONE 4

BR,TC,PAD,ZONE 4

J16

J10
J11
J12

J22

J21

J23

J24

PN: 2187010

PN:2187006

PN:2186997

RD (+) 12VDC, TERM BLOCK

BL (-) 12VDC, TERM BLOCK

DISP BRD, J6, 6PIN

PN:2186998

TO I/O 1A, J12, 8PIN

TO I/O 0B, J12, 8PIN

SW1

TO ICC WARMER ADAPTER

PN: 2187057

PN: 2187009

BR,AC L,LH TERM BLOCK

BU,AC N,LH TERM BLOCK

BU,AC N,LH TERM BLOCK

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

J17 J18

J20

J19

J21

J22

PN: 2187011

J23

J24

BR,PAD,ZONE 4,RH SIDE,MID

BR,AIR, ZONE 4,RH SIDE,MID

BR,PAD,ZONE 2,RH SIDE,BOT

BR,AIR,ZONE 2,RH SIDE,BOT

J5

BR,AC L,RH TERM BLOCK

BR,AC L,RH TERM BLOCK

BU, AC N,RH TERM BLOCK

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

60 Part Number MHCFA_Service Manual 03/16

Section 9 Wiring Diagrams

12VDC POWER SUPPLY

DISPLAY B0ARD

MHCFA34EX - Export 3x4

J3

J1

SW1

J6

J5

J4

RD(+)12VDC FROM PS

RD(+)12VDC TO KM

RD(+)12VDC TO LH SIDE

RD(+)12VDC TO RH I/O 1A

J2

I/O 0A,J10,6PIN

POWER CORD

BL(-)12VDC FROM PS

BL(-)12VDC TO KM

BL(-)12VDC TO LH SIDE

BL(-)12VDC TO RH I/O 1A

BR,AC L,TO TERM BLOCK SWITCH

BROWN

EMI FILTER

BLUE

GREEN/YELLOW

MOUNTED ON LH SIDE OF UNIT

BU,AC N,PAD 1

BU,AC N, PAD 2

BU,AC N, PAD 3

BU,AC N,JUMPER

INPUT POWER RELAY

BR, AC L,FROM SWITCH

PN: 2187019

PN: 2187035 OR 2187037 (GOES FROM LH TO RH SIDE)

RH - TERMINAL
BLOCK

BU, AC N,FROM SWITCH

PN: 2187017 OR 2187036

BU, AC N,TO TERM BLOCK
BU, AC N,TO POWER SWITCHBR,AC L,TO TERM POWER SWITCH

BR,AC L,FROM RELAY

BR,AC L, TO I/O 1A,J17,19,21,23

BR,AC L, TO I/O 0A,J17,19,21,23

BU,AC L,JUMPER

RD(+)12VDC FROM PS

RD(+)12VDC TO FAN 1

RD(+)12VDC TO FAN 2/3

RD(+)12VDC TO RH I/O 0A

GN, TO #10 GROUND STUD

BU,AC N,RH TERM BLOCK

BR,AC L,RH TERM BLOCK

PN: 2187013

BL(-)12VDC FROM PS

BL(-)12VDC TO FAN 1

BL(-)12VDC TO FAN 2/3

BL(-)12VDC TO I/O 0A

CN2 - 12VDC OUTPUT

CN1 - 100 TO 277VAC INPUT

BU,AC N,AIR 1

BU,AC N,AIR 2

BU,AC N,AIR 3

BU,AC N,JUMPER

BU,AC N, FROM RELAY

BU,AC N,TO LH SIDE

BU,AC N,TO PS

BU,AC N,JUMPER

BL(-)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

RD(+)12VDC,RH TERM BLOCK

RD(+)12VDC,RH TERM BLOCK

PN: 2187012

BR,AC L,TO LH SIDE

BR, AC L, TO PS

BU,AC L,JUMPER

Part Number MHCFA_Service Manual 03/16 61

Wiring Diagrams Section 9

MHCFA34EX - Export 3x4

MALE TERMINALS ON THIS END

BR,AIR,ZONE 5,LH SIDE

BR,PAD,ZONE 5,LH SIDE

LH - TOP ZONE - ZONE 5

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

YL,I/O 1A,J1(TC,AIR,TOP)

BR,I/O 1A,J18(AIR,TOP)*

BU,AC N,LH TERM BLOCK

BR,I/O 1A,J2(TC,PAD,TOP)

BR,I/O 1A,J20(PAD,TOP)*

BU,AC N,LH TERM BLOCK

*CONNECT AC LINE (BROWN) LEADS

TO PROPER TERMINALS ON HARNESS 2187014

FEMALE TERMINALS ON THIS END

BR,AIR,ZONE 5, RH SIDE, J18

BR,PAD, ZONE 5,LH SIZE,J20

PN: 2187014

RH - TOP ZONE - ZONE 6

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

YL,I/O 1A,J2(TC,AIR,TOP)

BR,I/O 1A,J22(AIR,TOP)

BU,AC N,LH TERM BLOCK

BR,I/O 1A,J4(TC,PAD,TOP)

BR,I/O 1A,J24(PAD,TOP)

BU,AC N,LH TERM BLOCK

LH - MIDDLE ZONE - ZONE 3

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

YL,I/O 0B,J3(TC,AIR,MID)

BR,I/O 0B,J22(AIR,MID)

BU,AC N,LH TERM BLOCK

BR,I/O 0B,J4(TC,PAD,MID)

BR,I/O 0B,J24(PAD,MID)

BU,AC N,LH TERM BLOCK

LH - BOTTOM ZONE - ZONE 1

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

YL,I/O 0B,J1(TC,AIR,BTM)

BR,I/O 0B,J18(AIR,BTM)

BU,AC N,TERM BLOCK

BR,I/O 0B,J2(TC,PAD,BTM)

BR,I/O 0B,J20(PAD,BTM)

BU,AC N,TERM BLOCK

RH - MIDDLE ZONE - ZONE 4

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

YL,I/O 0A,J3(TC,AIR,MID)

BR,I/O 0A,J22(AIR,MID)

BU,AC N,LH TERM BLOCK

BR,I/O 0A,J4(TC,PAD,MID)

BR,I/O 0A,J24(PAD,MID)

BU,AC N,LH TERM BLOCK

RH - BOTTOM ZONE - ZONE 2

RD(+)12VDC,RH TERM BLOCK

BL(-)12VDC,RH TERM BLOCK

YL,I/O 0A,J1(TC,AIR,BTM)

BR,I/O 0A,J18(AIR,BTM)

BU,AC N,TERM BLOCK

BR,I/O 0A,J2(TC,PAD,BTM)

BR,I/O 0A,J20(PAD,BTM)

BU,AC N,TERM BLOCK

62 Part Number MHCFA_Service Manual 03/16

Section 9 Wiring Diagrams

MHCFA34EX - Export 3x4

POWER SWITCH

J14

J8

J17

I/O 0B B0ARD - ZONES 1 AND 3

J15

J7

J18

PN: 2187017

BL, AC L,FROM RELAY

BU, AC N,FROM RELAY

BU, AC N,TO RELAY

PN:2187019

YL,TC,AIR,ZONE 1

BR,TC,PAD,ZONE 1

YL,TC,AIR,ZONE 3

BR,TC,PAD,ZONE 3

BR, AC L,TO RELAY

PN: 2187010

J1

J4J3J2

J16

J6

SW1

J10

J11

J19

J5

J14

J20

J21

J22

J12

J23

J24

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

PN: 2187006

FROM I/O 0A, J11, 8PIN

SW1

J18J17

PN: 2187009

LH ­TERMINAL BLOCK

RD(+)12VDC FROM RH SIDE

RD(+)12VDC TO FAN 1

RD(+)12VDC TO FAN 2/3

RD(+)12VDC TO I/O 0B

J20

J19

J21

BU,AC N,PAD 1

BU,AC N, PAD 2

BU,AC N, PAD 3

BU,AC N,FROM RH SIDE

BL(-)12VDC FROM RH SIDE

BL(-)12VDC TO FAN 1

BL(-)12VDC TO FAN 2/3

BL(-)12VDC TO I/O 0B

J22

J23

J24

BR,PAD,ZONE 3,LH SIDE,MID

BR,AIR,ZONE 3,LH SIDE,MID

BR,PAD,ZONE 1,LH SIDE,BOT

BR,AIR,ZONE 1,LH SIDE,BOT

BR,AC L,LH TERM BLOCK

BU,AC N,AIR 1

BU,AC N,AIR 2

BU,AC N,AIR 3

BU,AC N,FROM RH SIDE

J5

BR,AC L,RH SIDE

BR,AC L, TO I/O 0B

J17,19,21,23

Part Number MHCFA_Service Manual 03/16 63

Wiring Diagrams Section 9

MHCFA42EX - Export 4x2

POWER SWITCH

DISPLAY B0ARD

J3 J2

J1

SW1

J6

J5

J4

I/O 0A,J10,6PIN

POWER CORD

PN:2187019

PN: 2187019

GN,TO #10 GROUND STUD

BU,AC N,RH TERM BLOCK

BR,AC L,RH TERM BLOCK

PN: 2187013

EMI FILTER

BR,AC L,FROM EMI FILTER

BU,AC N,FROM EMI FILTER

BU,AC N,TO TERM BLOCK

BR,AC L,TO TERM BLOCK

12VDC POWER SUPPLY

CN1 - 100 TO 277VAC INPUT

CN2 - 12VDC OUTPUT

BL,AC L,TO POWER SWITCH

BU,AC N,TO POWER SWITCH

BL,(-)12VDC,RH TERM BLOCK

BL,(-)12VDC,RH TERM BLOCK

RD,(+)12VDC,RH TERM BLOCK

RD,(+)12VDC,RH TERM BLOCK

PN: 2187012

64 Part Number MHCFA_Service Manual 03/16

BU,AC N,TO TERM BLOCK

BU,AC N,FROM EMI FILTER

BR,AC L,FROM EMI FILTER

ROW 4 (TOP) - ZONE 4

BL,(-)12VDC,RH TERM BLOCK

RD,(+)12VDC,RH TERM BLOCK

RD,(+)12VDC,RH TERM BLOCK

BL,(-)12VDC,RH TERM BLOCK

PN: 2187012

BR,AC L,TO TERM BLOCK

12VDC POWER SUPPLY

CN1 - 100 TO 277VAC INPUT

CN2 - 12VDC OUTPUT

Section 9 Wiring Diagrams

MHCFA42EX - Export 4x2

ROW 3 - ZONE 3

RD,(+)12VDC,RH TERM BLOCK

BL,(-)12VDC,RH TERM BLOCK

YL,I/O 0A,J3(TC,AIR,MID)

BR,I/O 0A,J22(AIR,MID)

BU,AC N,LH TERM BLOCK

BR,I/O 0A,J4(TC,PAD,MID)

BR,I/O 0A,J24(PAD,MID)

BU,AC N,LH TERM BLOCK

ROW 2 - ZONE 2

RD,(+)12VDC,RH TERM BLOCK

BL,(-)12VDC,RH TERM BLOCK

YL,I/O 0A,J1(TC,AIR,BTM)

BR,I/O 0A,J18(AIR,BTM)

BU,AC N,TERM BLOCK

BR,I/O 0A,J2(TC,PAD,BTM)

BR,I/O 0A,J20(PAD,BTM)

BU,AC N,TERM BLOCK

RD,(+)12VDC,LH TERM BLOCK

BL,(-)12VDC,LH TERM BLOCK

YL,I/O 0B,J3(TC,AIR,MID)

BR,I/O 0B,J22(AIR,MID)

BU,AC N,LH TERM BLOCK

BR,I/O 0B,J4(TC,PAD,MID)

BR,I/O 0B,J24(PAD,MID)

BU,AC N,LH TERM BLOCK

ROW 1 (BOTTOM) - ZONE 1

RD,(+)12VDC,LH TERM BLOCK

BL,(-)12VDC,LH TERM BLOCK

YL,I/O 0B,J1(TC,AIR,BTM)

BR,I/O 0B,J18(AIR,BTM)

BU,AC N,TERM BLOCK

BR,I/O 0B,J2(TC,PAD,BTM)

BR,I/O 0B,J20(PAD,BTM)

BU,AC N,TERM BLOCK

RH - TERMINAL BLOCK

RD,(+)12VDC,FROM PS

RD,(+)12VDC,TO KM

RD,(+)12VDC,TO RH I/O OA

RD,(+)12VDC,FROM PS

RD,(+)12VDC,TO FAN 1

RD,(+)12VDC,TO FAN 2/3

RD,(+)12VDC,TO FAN 4

BL,(-)12VDC,FROM PS

BL,(-)12VDC,TO KM

BL,(-)12VDC,TO I/O 0A

BL,(-)12VDC,TO RH I/O 1ARD,(+)12VDC,TO RH I/O 1A

BU,AC N,PAD 1

BU,AC N,PAD 2

BU,AC N,PAD 3

BU,AC N,JUMPER

BL,(-)12VDC,FROM PS

BL,(-)12VDC,TO FAN 1

BL,(-)12VDC,TO FAN 2/3

BL,(-)12VDC,TO FAN 4

BU,AC N,PAD 4

BU,AC N,AIR 4

BU,AC N,JUMPER

BU,AC N,AIR 1

BU,AC N,AIR 2

BU,AC N,AIR 3

BU,AC N,JUMPER

BU,AC N,FROM SWITCH

BU,AC N,TO PS

BU,AC N,JUMPER

BU,AC N,JUMPER

BR,AC L,FROM SWITCH

BR,AC L,TO I/O 1A,J17,19,21,23

BR,AC L,TO I/O 0A,J17,19,21,23

BU,AC L,JUMPER

BR,AC L,TO PS

BU,AC L,JUMPER

Part Number MHCFA_Service Manual 03/16 65

Wiring Diagrams Section 9

MHCFA42EX - Export 4x2

I/O 0B B0ARD ­ZONES 1 AND 3

PN: 2187009

J14

J17

J15

J7J8

J18

YL,TC,AIR,ZONE 1
BR,TC,PAD,ZONE 1

YL,TC,AIR,ZONE 3

BR,TC,PAD,ZONE 3

PN: 2187010

J1

J18J17

J19

J4J3J2

J16

J6

SW1

J5

J14

J21J20

J20J19

J22

J10

J11

J12

J24J23

J23

J24

J22J21

BR,PAD,ZONE 3,LH SIDE,MID

BR,AIR,ZONE 3,LH SIDE,MID

BR,PAD,ZONE 1,LH SIDE,BOT

BR,AIR,ZONE 1,LH SIDE,BOT

RD(+)12VDC,LH TERM BLOCK

BL(-)12VDC,LH TERM BLOCK

PN: 2187006

FROM I/O 0A, J11, 8PIN

SW1

J5

BR,AC L,LH TERM BLOCK

I/O 0A B0ARD - ZONES 2 AND 4

PN:2187007

USB ADAPTER CABLE TO PANEL

MEMBRANE SWITCH,12 PIN RIBBON

MEMBRANE SWITCH,8 PIN RIBBON

PN: 2195357

TO ICC WARMER ADAPTER

PN: 2187057

PN: 2187009

J14

J8

J17

J17 J18

J1

J15

J7

J18

J2 J3 J4

J6

J19 J20

J19 J20

YL,TC,AIR,ZONE 2
BR,TC,PAD,ZONE 2

YL,TC,AIR,ZONE 4

BR,TC,PAD,ZONE 4

J16

SW1

J5

J14

J21 J22

J23 J24

J23

J21 J22

J10

J11

J12

J24

BR,PAD,ZONE 4,RH SIDE,MID

BR,AIR, ZONE 4,RH SIDE,MID

BR,PAD,ZONE 2,RH SIDE,BOT

BR,AIR,ZONE 2,RH SIDE,BOT

PN: 2187010

RD (+) 12VDC, TERM BLOCK

BL (-) 12VDC, TERM BLOCK

PN:2186998

PN:2187006

PN:2186997

BR,AC L,RH TERM BLOCK

DISP BRD, J6, 6PIN

TO I/O 1A, J12, 8PIN

TO I/O 0B, J12, 8PIN

SW1

J5

66 Part Number MHCFA_Service Manual 03/16

MERCO

980 SOUTH ISABELLA ROAD, MOUNT PLEASANT, MI 48858

800-678-9511

WWW.MERCOPRODUCTS.COM

Every new piece of Manitowoc Foodservice equipment comes with KitchenCare™ and you choose the level of service that meets
your operational needs from one restaurant to multiple locations.

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ExtraCare — CareCode, 24/7 Support, online/mobile product information

LifeCare – Install & equipment orientation, planned maintenance, KitchenConnect™, MenuConnect

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www.manitowocfoodservice.com, then discover the regional or local resources available to you.

©2016 Manitowoc Foodservice except where explicitly stated otherwise. All rights reserved. Continuing product improvement may necessitate change of specications without notice.

Part Number MHCFA_Service Manual 03/16