Multiplex ERC Programming Modes

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Multiplex ERC

Part I

• Upon Powering the ERC and after the PD30 Power Delay countdown, the display will show CD99 (Compressor Delay + 99
seconds) and will start to count down from 99 seconds after the first 81 seconds have elapsed. (180 Total Seconds on
countdown)

• After 180 seconds the compressor and condenser fan motor energize and the COMP/AGIT LED flashes. Pressing the CARB
A and CARB B buttons will immediately energize the carbonator pumps. The corresponding LED flashes to indicate the
pump is running. Pressing the CIRC A & CIRC B buttons will immediately energize the circulating pumps and energize the
LED constantly. The display will show the circulating temperature and alternate between A and B circuits every 5 seconds.

Multiplex ERC Board Identification – This will help identify the
sensor position on the control board. We will provide the part
number and description for each one by the number.

1,2 – ELECTRODE RED (part#19714)
1,2 – ELECTRODE BLACK (part#19715)
1,2 – CORD ASSEMBLY TO CARB TANK (part#119604)
3 – SENSOR,CONTROL,ICE BANK,ERC (part#117849)
4 – SENSOR,LEVEL,H2O BATH,ERC (part#120883)
5 – SENSOR,TEMP,RCRC,SCTN,DSCHG,ERC (part#118125)
6 – SENSOR,TEMP,RCRC,SCTN,DSCHG,ERC (part#118125)
7 – SENSOR,TEMP,H20 BATH,ERC (part#118678)
8 – SENSOR,TEMP,RCRC,SCTN,DSCHG,ERC (part#118125)
9 – SENSOR,TEMP,RCRC,SCTN,DSCHG,ERC (part#118125)
10 – TRANSDUCER,PRESSURE,0-150PSI (part#118917)
10 – Harness for Transducer (H2O) (part#121117)
11 – (NOT USED)
12 - SWITCH,HI PRESSURE,CUT-OUT (part#117202)
12 – Harness for HPCO (part#121118)

Multiplex ERC Tips –

• Every 5 seconds, the temperature for A & B is
displayed. If you read a temperature that
does not compare, you have a defective
sensor and that sensor can be unplugged until
it’s replaced.

• The board can be “reset” by turning off power
at the wall panel or breaker for at least (one
minute)

• When the “CIRC A & B” LED is flashing, it
indicates Energy Savings Mode is active.

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Multiplex ERC Checking Sensor Readings via Display – TO ENTER PROGRAM MODE 1, PRESS AND HOLD THE PGM SWITCH

FOR MINIMUM OF 3 SECONDS OR UNTIL THE DISPLAY SHOWS “0001” – WITHIN 3 SECONDS, IT WILL DEFAULT TO C000

Note: Before entering any program by pressing the “PGM” button, always make sure both carbonators are satisfied. If entering
the program while a carbonator is cycling, it will continue to run and blow the relief valve.

Shorted Transducer = "----"
Open Transducer = "===="

PGM to ENTER/Advance

Green = C000 Mode (Conductivity)

** Select PGM once to Advance to F000 **

Blue = F000 Mode (Temperature)

** Select PGM once to Advance to P000 **

Red = P000 Mode (Pressure)

Press and Hold CIRC A Switch to
show Water Level Probe (Bath)
“CL 1” = Water Level OK
“CL 0” = Water Level Low

Press and Hold CARB A Switch to show LLC Probe Press/Tap COMP/AGIT to Press and Hold CIRC B Switch -
CA00 — High & Low Probes are open (No Water) toggle between F000 Display will indicate Suction Temperature
(carbonator motor is energized) (Fahrenheit) and FC00
CA11 — High & Low Probes are closed (In Water) (Centigrade) Press and Hold CIRC A Switch — Display will
(carbonator motor is de-energized) indicate Liquid Line Temperature
CA01 — Low Probe is closed (In Water)(Motor will
still be on until High probe gets water)
------------------------------------------------------------------
Press and Hold CARB B Switch to show LLC Probe
Cb00 — High & Low Probes are open (No Water)
(carbonator motor is energized)
Cb11 — High & Low Probes are closed (In Water)
(carbonator motor is de-energized)
Cb01 — Low Probe in closed (In Water)(Motor will
still be on until High probe gets water)

Press and Hold COMP/AGIT Switch to show ICE BANK PROBE Press and Hold CARB A switch — Display will indicate
“CC11” = NO ICE - COMPRESSOR ON Water Bath Temperature
“CC10” = ICE ON LOW - SENSOR COMPRESSOR OFF
“CC00” = ICE BANK TOO LARGE (E7) Press and Hold CARB A switch — Display will
indicate Water Pressure

SYMPTOM:
Large ice bank in right front corner of the
evaporator and/or frost back to the compressor

There were some Multiplex Remote units that were shipped with the Ice
Bank Probe on the “LEFT” side of the plastic “A” bracket. A service bulletin
was issued and instructed to reposition it to the “RIGHT” side of the bracket.
See the image to get the visual. Since, MBS (Multiplex has corrected this on
the production line) This only affects several hundred units early in
production. It since has been corrected for the past few years. It would not
hurt to visually check the position and ensure it’s correct. Remember, the
green wire should be closest to the agitator.

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Multiplex ERC – Part II
There are 5 programming modes: (4 on older ERCs)

/Ŷ WĂƌƚ /, we highlighted Program Mode 1. That was the absolute longest one of all and the one you will access the most. It’s

your troubleshooting program mode to detect which component has failed or lead you to a proper diagnosis. Once familiar

with Program Mode 1, you can troubleshoot over 90% of ERC problems. Let’s recap what Program Mode 1 is used for:
• Check Probes
• Check Temperatures
• Water Bath Level
• Set Unit of Measure

This week we focus on what is Program Mode 2. It’s function is to “Add additional (third or fourth) circulation pumps”.
This function should NEVER be enabled to change the CARBONATORS to CIRCULATORS (CIRC C and/or CIRC D)

TO ENTER PROGRAM MODE 2, PRESS AND HOLD THE PGM SWITCH FOR MINIMUM OF 3 SECONDS OR UNTIL THE DISPLAY SHOWS
“0001” – WITHIN 3 SECONDS, PRESS PGM SWITCH AGAIN – DISPLAY SHOWS “0002” – WAIT 3 SECONDS – DISPLAY SHOWS “-002” =
(Factory Default)

-002 PGM to ENTER/Advance

We ALWAYS want to see “-002” !

Pressing CIRC B button energizes/de-energizes pump B

Pressing CIRC A button energizes/de-energizes pump A

Program CIRC C - Press Program CIRC D - Press Note: It would also require some wire
CARB A button – Display CARB B button – Display connections be altered at the main board but
shows -102 = Carb A shows -012 = Carb B there is no need to mention it because we are
button energizes/de- button energizes/de-
energizes pump C energizes pump D ALWAYS required to be in beverage mode.

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Multiplex ERC – Part III (Final)
There are 5 programming modes: (4 on older ERCs)
/Ŷ WĂƌƚ ///͕ we focus on Program Mode 3, 4͕ & 5.

** Program Mode 3 ** - This mode is for Beermaster units only and NOT used on Soda or Water
refrigeration systems. This function should NEVER be active.

TO ENTER PROGRAM MODE 3, PRESS AND HOLD THE PGM SWITCH FOR MINIMUM OF 3 SECONDS OR UNTIL THE DISPLAY SHOWS
“0001” – WITHIN 3 SECONDS, PRESS PGM SWITCH TWICE – DISPLAY SHOWS “0003” – WAIT 3 SECONDS – DISPLAY SHOWS “-003” =
(Factory Default)

-003 PGM to ENTER/Advance

Press the COMP/AGIT button once to toggle to We ALWAYS want to see “-003” !
BEER MODE.
WARNING: If BEER MODE is ON, the water bath
will be set to 27°F factory default temperature
set point and freeze. Do not place Soda or Water

refrigeration units in BEER MODE.

1--3 1273

BEER MODE OFF = Display shows 1- -3 BEER MODE ON = Display shows 1273

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** Program Mode 4 ** - This mode is accessed to “Temporarily Cancel Display of Error Codes”.

TO ENTER PROGRAM MODE 4, PRESS AND HOLD THE PGM SWITCH FOR MINIMUM OF 3 SECONDS OR UNTIL THE DISPLAY
SHOWS “0001” – WITHIN 3 SECONDS, PRESS PGM SWITCH THREE TIMES – DISPLAY SHOWS “0004” – WAIT 3 SECONDS –

DISPLAY SHOWS “-004” - Press COMP/AGIT button once - Display shows ---4 (error codes will not be displayed during run

mode)

-004 ---4

NOTE: Disconnecting and reconnecting main power will reset the control board to the factory

setting -004 = Error codes will be displayed in the run mode – This mode is the second most used
mode. You can perform deep troubleshooting using this mode.

** Program Mode 5 ** - This mode is called the Energy-Saving Program Mode for “G” models only and
any ERC unit that gets a new control board replaced. All “G” series were shipped with this function.

** Warning** - This mode is active when shipped by the manufacturer. Coca-Cola should never change
this function on any customer request or alter as a repair. Any alterations for this mode will come as Ă
McDonald’s “official” bulletin.

TO ENTER PROGRAM MODE 5, PRESS AND HOLD THE PGM SWITCH FOR MINIMUM OF 3 SECONDS OR UNTIL THE DISPLAY SHOWS
“0001” – WITHIN 3 SECONDS, PRESS PGM SWITCH FOUR (4) TIMES – DISPLAY SHOWS “0005” – WAIT 3 SECONDS – DISPLAY SHOWS
“-X-5” - NOTE: If 0005, fails to display you have an incompatible version of the ERC control board and this mode is not available.

Press the COMP/AGIT button to enable/disable ---5
energy savings mode.

-0-5

-0-5 = Energy savings mode enabled ---5 = Energy savings mode disabled

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** ERC Operation/Information in Mode 5 **

Circulating motor LED will flash once per second if energy saving PGM mode 5 is enabled. The LED will stay constantly ON if
energy saving PGM mode 5 is disabled. The ERC control monitors all carb motors for entering energy savings cycle mode if no
carb cycles in 30 minutes, no ERC error codes or sensors open / shorted, and circulating temperature = < 38°F then energy
savings cycle mode will be entered.

NOTE: Display adds “o” to left digit to indicate in energy savings cycle mode “oxxF” (Fahrenheit) if you see “oxxc” (Centigrade), call.
1. If circ temp = < 36°F - energy savings cycle mode off time is 10 minutes
2. If circ temp = < 37°F - and >36°F energy savings cycle mode off time is 8 minutes
3. If circ temp = < 38°F - and >37°F energy savings cycle mode off time is 6 minutes
4. If circ temp = > 38°F - then no energy savings cycle mode entered

Agitator and circulator will be turned off when in energy savings cycle mode off time. When energy savings cycle mode off
time is completed, agitator and circulator motors will be turned on in energy savings cycle mode on time.
Motors will stay on until temperature entered mode is reached; 36°F, >36-37°F, >37-38°F

Energy savings cycle mode will repeat (off time 10, 8, 6 minutes depending on entering temp, then on again till entering temp
reached).
Energy savings cycle mode is exited when;
- Any carb cycle occurs
- Any error code occurs
- Circulating temperature exceeds 38°F
- Display changes to normal run mode, circulating LED flashes for controlled ON. System waits for another 30 minute period

without carb cycle to enter energy savings cycle mode again.

Whew! Congratulations! You have completed the Multiplex ERC Modes. Take a 2 minute break and grab a refreshing
ŽĐĂͲCola product and let all that information sink in.