Kutzner + Weber MUC User manual

KUTZNER +WEBER
MUC Multi Use Controller
INSTALLATION INSTRUCTIONS

MUCIOM
2|Page

Contents
1. Introduction 3
2. Specifications 4
3. Component List 5
4. Installation 6
a. Mounting 6
b. Electrical 7
c. Battery Installation and Removal 9
d. GFS Differential Air Pressure Switch
Exhaust Applications (GF/ GH)
10
e. CS75 Current Switch
Supply Air System (SA)
13
e. GFS Differential Air Pressure Switch
Supply Air System (SA)
15
5. Operation 19
a. Modes 19
b. Inputs and Outputs 22
c. Flow Chart 24
c. Troubleshooting 25
6. Reference List 26

MUCIOM
3|Page

Multi Use Controller (MUC) IOM
Installation, Operation and Maintenance Manual
Please read and save these instructions for future reference. The proper installation and
maintenance of this unit will allow the unit to deliver years of dependable service. Read
carefully before attempting to assemble, install, operate or maintain the product
described. Protect yourself and others by observing all safety information. Failure to
comply with instructions could result in personal injury and/or property damage!
Installation and maintenance are to be performed only by qualified personnel who are
familiar with local codes and regulations and who are experienced with this type of
equipment. Personnel should have a clear understanding of these instructions and
should be aware of general safety precautions.
DANGER! Always disconnect, lock and tag power source before installing or servicing.
Failure to disconnect power source can result in fire, shock or serious injury.
CAUTION! Consult and follow all applicable national, state and local codes. They will
supersede this document.
WARNING! No installation, use or maintenance should be done in an explosive or
hazardous environment.
Introduction
The Multi Use Controller (MUC) is an intelligent easy to install wall mounted device that
is a constant speed controller used to safely exhaust or provide supply air to gas or
solid fuel fired fireplaces and heating appliances. Designed for use with electronically
commutated motors (ECM), the MUC meets all code requirements for NFPA211,
NFPA54, IFGC2012, IMC2012 and UMC2012
Features include:
 User control via Integrated slide switch 0-10 VDC potentiometer to control a draft
inducer or power venter
 Enable input for remote operation
 Code compliant safety mechanism designed for ECM fault protection
 Visual and audible alarm if the controller detects a problem with the fan
 Includes an integrated safety function to verify the pressure is negative or if the
motor is functioning properly as required per national and local codes
 Device status indicators via a green LED and red LED as well as an audio
buzzer that can be muted
 Includes a battery back-up if the control loses power
Note: Information contained within this manual may be updated without notice.

MUCIOM
4|Page

Specifications
Power Supply 24 VDC (non-isolated half-wave rectified)
Consumption 32 mA max @ 24 VDC (Run Mode)
Protection Circuitry Reverse voltage protected, overvoltage protected
Operating Conditions 4-32 C (40-90 F), 20-80 %RH non-condensing
Wiring Connections Screw terminal block (14 to 22 AWG)
Enclosure Wall mount enclosure, 3.3”w x 4.7”h x 1.15”d
(84 x 119 x 29 mm)
Relay Output Contact Ratings Form C contact (N.O. + N.C.), 5 Amps @ 250 VAC, 5
Amps @ 30 VDC
Slide Potentiometer Front panel pot is two-wire resistive output,
0-10 K standard
Analog Output 0-10 VDC
Audio Mute Switch Front panel push-button dry contact
LEDs Red LED =Super Bright, Low Current,
Green LED =Super Bright, Low Current
Audio Buzzer 3V, 2700 Hz +/- 200 Hz, SPL = 80 dBA
Back Up Battery 2 x CR2032 Lithium-Manganese Dioxide Coin Cells, 3V,
220 mAH, 3.0 x 20.0 x 20.0 mm

MUCIOM
5|Page

Component List
The MUC system is made up of several components dependent on the application:
1. MUC Controller
2. System Application Components
a. GF : gas fireplace system
i. Draft inducer / vent fan
1. VFD included with induction motors
ii. GFS: differential air pressure switch
iii. Vent probe and tubing
iv. Power supply (24 VDC)
b. GH : gas heating appliance system
i. Draft inducer / vent fan
1. VFD included with induction motors
ii. GFS: differential air pressure switch
iii. Vent probe and tubing
iv. Power supply (24 VDC)
c. SA : supply air system
i. Supply fan
ii. CS75 current switch
iii. Power supply (24 VDC)
d. SF : solid fuel fireplace system
i. Draft inducer / vent fan
ii. Power supply (24 VDC)
3. Optional / Additional Components
a. CO detector
b. GFS: differential air pressure switch
c. Spill switch kit(s)
d. XB expansion board

MUCIOM
6|Page

Installation of the MUC
Before Installation
Read these instructions carefully before installing and commissioning the device.
Failure to follow these instructions may result in product damage. Do not use in an
explosive or hazardous environment, with combustible or flammable gases, as a
safety or emergency stop device or in any other application where failure of the product
could result in personal injury. Take electrostatic discharge precautions during
installation and do not exceed the device ratings.
Mounting
The Multi Use Controller (MUC) installs directly on a standard electrical box. The cover
is hooked to the base at the top edge and must be removed from the bottom edge first.
Use a small screwdriver to carefully pry each bottom corner if necessary. If a security
screw is installed on the bottom edge, then it may have to be loosened or removed also.
Tip the cover away from the base and set it aside.
The MUC must be removed from the base to access the mounting holes. Follow normal
anti-static procedures when handling the MUC and be careful not to damage any
components. The MUC is removed by pressing the enclosure base to unsnap the latch
near the bottom edge, then the MUC can be lifted out of the base. Sit the MUC aside
until the base is mounted.
After the base is screwed to an electrical box
or the wall using the appropriate holes, pull
the wires through the wiring hole in the center
of the MUC and then reinstall it in the
enclosure base. Ensure the MUC is snapped
into the base securely and correctly.
The mounting hole locations are shown on
figure 1:
Figure 1

MUCIOM
7|Page

Electrical
The MUC may be wired for different applications. Review the supplied wiring diagram(s)
and verify the application before attempting to connect the MUC to any associated
components or equipment. Follow all local electrical and safety codes, as well as the
National Electrical Code (NEC) and the National Fire Protection Agency (NFPA), where
applicable. Follow the Canadian Electric Code (CEC) in Canada.
Note: Use 18 AWG shielded wire for all low voltage connections. Do not locate the
device wires in the same conduit with high voltage wiring or used to supply
inductive loads such as motors.
Disconnect the power supply before making any connections to prevent electrical shock
or equipment damage. Follow proper electrostatic discharge (ESD) handling procedures
when installing the device or equipment damage may occur.
24 VDC From GFS Pressure Switch
24 V
To Fan Motor Speed Input
Dampe
r
Relay
ENABLE
Gas
Relay
Green LED (RUN)
Red LED (Fail)
Battery Tray
A
udio Mute Switch
A
udio Buzze
r
Slide Control Potentiomete
r

Cut Out
COM
POT
MSTAT
Dampe
r
Gas
COM
COM
N.C.
N.C.
N.O.
N.O.
24 VDC From Remote Unit
Common
24 VDC From Power Supply
BATT
ON
OFF
Battery Enable Jumper Select
RPM BYPASS Enable
Jumper Select
PROVER
+5V
RPM
Motor Status Feedback Voltage
5 VDC To Moto
r

Motor RPM Feedback Signal
RPM BYPASS
ONOFF
Figure 2

MUCIOM
8|Page

Power Connections
The MUC requires a 24 VDC power supply to operate. The device has a half-wave type
power supply so the power supply common is the same as the output signal common.
Several devices may be connected to one power supply and share the same signal
common.
Use caution when grounding the secondary of a power supply or when wiring multiple
devices. Ensure that the circuit ground points are the same on all devices.
Connect the positive DC voltage to the 24V terminal and the power supply common to
the COM terminal. The device is reverse voltage protected and will not operate if the
power supply is connected backwards.
Note: the COM terminal is NOT connected to the Relay COM terminals.
Heating Appliance Connections
Refer to the appliance manufacturer's instructions or contact the appliance
manufacture for specific connections within the appliance.
Enable Input (remote operation)
Many appliances have a dry contact to enable external devices (louvers, pumps, etc.)
built into the appliance control system. Those that don't may require a relay to be field
installed within the appliance to provide the necessary dry contact for the Enable
(remote) signal to the MUC.
Note: Install a jumper between 24V to ENABLE when remote operation is not required
Relay Wiring
The MUC relay outputs are completely isolated. The gas and damper relays each have
their own 3 terminal connection block, each with a COM, N.O. (Normally Open) contact
and N.C. (Normally Closed) contact. Connect the gas valve and damper relay
connections as per the labeled terminal blocks for each as illustrated in the system
wiring diagrams for the N.O. (normally Open) contact operational control.
 The gas relay is the interlock for enabling the heating appliance or gas log set
when all the safety and run conditions are proven
 The damper relay is for enabling an external device such as a damper or VFD
when the MUC is enabled to run
Motor Connections
Connect the fan motor as per the supplied system diagram for the motor type.

MUCIOM
9|Page

Battery Insertion and Removal
After the MUC has been wired completely into the system insert the backup
battery tray into its holder on the MUC.
When normal operating power is provided to the MUC the device will enter normal
operating mode and exit back up mode.
To insert the backup batteries into the MUC simply slide and push the battery tray into
the battery holder on the MUC as illustrated in figure 3, ensuring that the positive
terminal is facing upwards. To remove the battery tray from the battery holder on the
MUC simply push on either the bottom or top battery tray tab to pop the tray slightly out
from the battery holder on the MUC and then pull the tray out from the battery holder as
illustrated in figure 3.
Battery Removal
1. Push either tab to pop battery tray
slightly out
2. Then slide tray out from holder
Battery Holder with inserted
battery tray
Battery Holder
Battery Tray
1. Push and slide battery tray into 
holder
Battery Insertion
Figure 3

MUCIOM
10|Page

GFS Differential Air Pressure Switch Installation
Systems with a gas heating appliance or gas log set require a GFS differential air
pressure switch to prove fan function and available draft in the venting system.
Mounting
Check the pressure switch for damages. Do not use if damaged! Do not mount the
pressure switch on uneven, hot, or vibrating surfaces! Do not tighten the screws too
much, in order to avoid deforming of the device’s base. Mount the pressure switch with
the pressure connections pointing downwards, to drain condensation moisture which
might occur. In general, the mounting with two screws next to each other is sufficient.
The maximum diameter of the screws must not be bigger than 0.315" (8 mm).
Pneumatic Connections
The two pressure ports on the end of the enclosure are labeled P1(+) and P2(-). Ensure
these ports are connected correctly and that the shipping cap is removed from port(s).
Install the vent probe as close to the fan as possible on a fireplace system, figure 5. On
a gas heating appliance vent system install the vent probe in the common, figure 6.
Then connect the pressure tubing between the vent probe and the P2(-) port on the
GFS pressure switch. Use the supplied high temperature 0.170” I.D. flexible tubing for
the pressure connections.
If mounting location is farther than 10ft use 0.25" I.D. rigid tubing. Cut 2 short pieces of
the supplied tubing and use as couplings for proper sealing, heat isolation and ease
of installation. Arrange the tubing to minimize stress on the connections and ensure
there are no kinks in the tubing. In vent systems it is recommended that the tubing slope
back to the vent for draining to prevent condensate from collecting in the sensing line.
Ensure the tubing is clean and do not allow material to fall into the pressure ports as
contamination could damage the switching mechanism. When removing tubing use care
to avoid breaking the ports.
Figure 4

MUCIOM
11|Page

GFS Differential Air Pressure Switch Installation
1"MAXIMUM PENETRATION
PRESSURE TUBING
TYPICAL FLUE
TYPICAL FIREPLACE
W/ GAS LOG SET
VENT PROBE
GFS
PRESSURE SWITCH
P+
LEFT OPEN TO ROOM
P-
FLOW TO FAN
CB TERMINATION FAN
1"MAXIMUM PENETRATION
PRESSURE TUBING
TYPICAL EXHAUST FLUE
TYPICAL BOILER/WATER HEATER
VENT PROBE
GFS
PRESSURE SWITCH
P+
LEFT OPEN TO ROOM
P-
FLOW TO FAN
ALTERNATIVE VENT PROBE PLACEMENT
EXHAUST FLUE
180°
VENT PROBE MAY ALSO BE INSTALLED
ALONG LENGTH OF FLUE ABOVE HORIZONTAL
VENT PROBE

Figure 5
Figure 6

MUCIOM
12|Page

GFS Differential Air Pressure Switch Installation
Electrical
Connect Insert a conduit tube with 1/2” thread and tighten with a torque of 2.5 Nm.
Assemble flex- and conductors accordingly.
Note: This is a low voltage circuit. Do not run low voltage conductors with high voltage
conductors.
Make and verify connections per supplied system wiring diagram. The connections are
intended for 0.25" (6.3 mm) crimp-type sockets. The switch (P) in the pressure switch is
designed as a change-over contact. Pole 3 (COM) closes to pole 2 (NO) at increasing
pressure and to pole 1 (NC) at decreasing pressure.
Connections for GFS
MUC Terminal To GFS Terminal
24V (DC) ↔ 3
Prover ↔ 2
Switching Pressure Adjustment
Caution! Make absolutely sure that no voltage is applied to the electrical connections,
before any settings on the pressure switch are carried out.
Set the desired pressure, which trips the switch at decreasing pressure, on the setting
button using a screwdriver. When the pressure falls, the switch returns into its resting
position, as soon as the pressure falls below the set switching differential. Place the
cover and screw it to the pressure switch. Do not operate the system until the housing is
closed. Check the trip and reset pressure by slowly increasing and decreasing pressure.
Switch should be adjusted so that it makes upon vent fan enabling and opens when fan
stops.

MUCIOM
13|Page

CS75 Current Switch for Supply Fan Installation
The CS75 current switch monitors line current of the supply fan for proof of operation.
The switch closes the output contacts and energizes an onboard LED when the
adjustable trip point is exceeded. The CS75 factory set trip point is 0.75A with a
maximum adjustment range between 0.75 to 75A. The switch should be adjusted for the
specific installation and site conditions for proper system operation.
Mounting
Check the CS75 current switch for damages. Do not
use if damaged! Do not mount the switch on uneven,
hot, or extreme vibrating surfaces! Mount the CS75
using two screws through the holes in the base. Install
within an appropriate electrical enclosure. Do not
tighten the screws too much, in order to avoid
damaging the CS75 base.
Electrical
Caution, danger to life!
Make absolutely sure that all voltage sources are secured before making any
electrical connections!
Disconnect the power supply before making any connections to prevent electrical shock
or equipment damage. Make all connections in accordance with national and local
electrical codes. Route the load conductor to be monitored through the sensor hole in
the CS75 current switch (Figure 8). Ensure the conductors are insulated and in good
condition.





Figure 7
Figure 8

MUCIOM
14|Page

CS75 Current Switch for Supply Fan Installation (continued)

Note: This is a low voltage circuit. Do not run low voltage conductors with high voltage
conductors.
Connections for CS75
MUC Terminal To CS75 Terminal
24V (DC) ↔ Either
Prover ↔ Either
Switch Adjustment
With the sensor installed, energize supply fan.
Enable the MUC controller and adjust so that the
supply fan is running at minimum speed or normal
speed if non-adjustable.
The CS is factory set to switch at 0.75 Amps the
status LED should be lit and the contacts should
be closed if the supply fan motor draws more than
0.75 Amps at minimum speed.
With the supply fan running at minimum speed, rotate the multi-turn set point pot
counter-clockwise until the status LED turns off. Then slowly turn the pot clockwise until
the LED just comes on. Turn clockwise slightly more to eliminate false switching.
Test setting using a voltmeter across the contacts to verify switch operation. Disable the
MUC controller. The supply fan should go into standby mode. The CS contacts should
open and the LED off. If not readjust the CS switch and retest. After passing this test the
CS is now set to detect the supply fan operational condition.
For applications with very small load currents at minimum speed (such as less than 1
Amp), wrap the monitored conductor through the sensor aperture several times to
increase the current measured by the sensor.
For example, to monitor a 0-1 Amp load with a CS75, wrap the conductor through the
sensor aperture 5 times so the sensor actually sees 0-5 Amps. For any application with
multiple wraps, note that the CS75 maximum current rating must be divided by the
number of wraps. For example, with one wrap the maximum current is 75 Amps, with 5
wraps the maximum current is 75/5 = 15 Amps. Ensure the load current is < 15 Amps or
the device may overheat and be damaged.
Figure 9

MUCIOM
15|Page

GFS Differential Air Pressure Switch for Supply Fan Installation
The GFS differential air pressure switch can be used as an alternate or complementary
device to the CS75 current switch for supply fan applications. The GFS differential air
pressure switch monitors outlet pressure of the supply fan for proof of operation.
The GFS switch normally open contact closes when the adjustable trip point is
exceeded. The GFS factory set trip point is 0.08 "WC with a maximum adjustment range
between 0.08 to 0.8 "WC. The switch should be adjusted for the specific installation and
site conditions for proper system operation.
Mounting
Check the pressure switch for damages. Do not use if damaged! Do not mount the
pressure switch on uneven, hot, or vibrating surfaces! Do not tighten the screws too
much, in order to avoid deforming of the device’s base. Mount the pressure switch
with the pressure connections pointing downwards, to drain condensation moisture
which might occur. In general, the mounting with two screws next to each other is
sufficient. The maximum diameter of the screws must not be bigger than 0.315" (8
mm).
Figure 10


MUCIOM
16|Page

GFS Pneumatic Connections for Supply Fan (continued)
Pneumatic Connections
Remove plastic shipping cap(s) from the pressure port(s) on the end of the enclosure
labeled P1(+) and P2(-) (Figure 10).
Option 1: Connect the tubing between the pressure probe on the discharge side of the
supply fan outlet or duct and the P1(+) on the GFS (Figure 11). Use the supplied 0.170”
I.D. flexible tubing for the pressure connections.
Option 2 (low pressure applications): Connect the tubing between the pressure
probe on the discharge side of the supply fan outlet or duct and the P1(+) on the GFS.
Install a second pressure probe on the inlet side of the fan or duct. Connect additional
pressure tube to the P2(-) port.
Arrange the tubing to minimize stress on the connections and ensure there are no kinks
in the tubing. Ensure the tubing is clean and do not allow material to fall into the
pressure ports as contamination could damage the switch or block pressure signal.
Figure 11

MUCIOM
17|Page

GFS Differential Air Pressure Switch for Supply Fan (continued)
Electrical
Caution, danger to life!
Make absolutely sure that all voltage sources are secured before making any
electrical connections!
Disconnect the power supply before making any connections to prevent electrical shock
or equipment damage. Make all connections in accordance with national and local
electrical codes. Make and verify connections per supplied system wiring diagram.
Note: This is a low voltage circuit. Do not run low voltage conductors with high voltage
conductors.
Insert a conduit tube with 1/2” thread and tighten with a torque of 2.5 Nm.
Assemble flex- and conductors accordingly.
The connections are intended for 0.25" (6.3 mm) crimp-type sockets. The switch (P) in
the pressure switch is designed as a change-over contact. Pole 3 (COM) closes to pole
2 (NO) at increasing pressure and to pole 1 (NC) at decreasing pressure.
Connections for GFS
MUC Terminal To GFS Terminal
24V (DC) ↔ 3
Prover ↔ 2

MUCIOM
18|Page

GFS Differential Air Pressure Switch for Supply Fan (continued)
Switching Pressure Adjustment
Caution, danger to life!
Make absolutely sure that no voltage is applied to the electrical connections,
before any settings on the pressure switch are carried out.
Set the desired pressure, which trips the switch at increasing pressure, on the
setting button using a screwdriver. When the pressure falls, the switch returns into
its resting position, as soon as the pressure falls below the set switching differential.
Place the cover and screw it to the pressure switch. Do not operate the system until
the housing is closed.
Check the trip and reset pressure by slowly increasing and decreasing pressure.
Switch should be adjusted so that it makes upon supply fan enabling and opens
when supply fan stops. If more switch sensitivity is needed refer to pneumatic
connections option 2.
Additionally, if system discharge is open to a space, the speed setting may be
increased till the GFS switch makes or the discharge adjusted to increase discharge
back pressure.

MUCIOM
19|Page

Operation - Modes
Run Mode 1 (Slide pot)
When the MUC provides at least 2VDC (from slide pot) and the ENABLE input is
energized it will turn on the green LED and energize the damper relay to the closed
position.
The gas relay will still remain in the normally open position until the PROVER circuit
input is energized by 24VDC, the motor ON voltage feedback is >4 VDC, and the motor
RPM frequency feedback is >150 pulses per second. If these requirements are not met
within 15 seconds after the start command the MUC will go into Fail mode.
If the controller is in Run Mode and experiences a power loss, then the device enters
the Back Up Mode with the alarm being activated.
Off Mode 1 (Slide pot)
When the MUC potentiometer is adjusted to the Off position providing a <1.5 VDC
signal to the fan motor, the MUC enters Off Mode. The MUC will deactivate the red
LED, green LED and alarm buzzer, and releases both the gas relay and damper relay
into the normally open position.
Run Mode 2 (Enable Input)
When the MUC Enable input terminal is energized and the slide pot is >2VDC it will turn
on the green LED and energize the damper relay to the closed position.
The gas relay will still remain in the normally open position until the PROVER circuit
input is energized by 24VDC, the motor ON voltage feedback is >4 VDC, and the motor
RPM frequency feedback is >150 pulses per second. If these requirements are not met
within 15 seconds after the start command the MUC will go into Fail Mode.
If the controller is in Run Mode and experiences a power loss, then the device enters
the Back Up Mode with the alarm being activated.
Off Mode 2 (Enable Input)
When the Enable input terminal loses the 24VDC input the MUC will deactivate the red
LED, green LED and alarm buzzer, and releases the gas relay into the normally open
position and begins a 60 second (post purge) output off delay timer. After the timer
expires the MUC will secure the 0-10VDC analog speed signal to motor and releases
the damper relay into the normally open position.

MUCIOM
20|Page

Operation - Modes
Fail Mode (Alarm)
The MUC after a 15 second delay will deactivate the green LED, activate the red LED,
activate the alarm buzzer and releases the gas relay into the normally open position if
any or combination of the following occurs:
1. If the fan motor provides <4VDC
2. If the RPM frequency feedback is <150 pulses per seconds (if not by-passed by
jumper)
3. The Prover input is de-energized
The damper relay remains in the closed position during Fail Mode.
The MUC will automatically reset and resumes normal operation once the alarm
condition clears. If the MUC should receive the missing feedback signal while in the
Fail Mode for at least 2 seconds, then the MUC will return to the Run Mode and will
deactivate the red LED and alarm buzzer, activate the green LED and drive the gas
relay to the closed position.
During Fail Mode, an override (Mute/Silence) switch, when depressed will deactivate
the audio buzzer for 2 minutes. After 2 minutes if the MUC is still in Fail Mode, the audio
buzzer will be activated. Muted audio alert mode will flash the red LED with a 50% duty
cycle.