ENERVEX MEC 18 Installation & Operating Manual

ENERVEX
MEC 18 MECHANICAL EXHAUST CONTROL

3916010 06.16 Installation & Operating Manual

READ AND SAVE THESE INSTRUCTIONS!

ENERVEX Inc.
1685 Bluegrass Lakes
Parkway
Alpharetta, GA 30004
USA

P: 770.587.3238
F: 770.587.4731
T: 800.255.2923
[e-mail]
www.enervex.com

3916010 06.16

The MEC 18 Mechanical Exhaust Control is ETL Listed in the U.S. and Canada: under file #302882A

Symbol Legend

The following terms are used throughout this manual to bring
attention to the presence of potential hazards, or to important
information concerning the product.

DANGER: Indicates an imminent hazardous
situation which, if not avoided, will result in death,
serious injury or substantial property damage.

WARNING: Indicates an imminent hazardous
situation which, if not avoided, may result in
personal injury or property damage.

How to use this manual

This installation manual does not contain any system design
documentation. System design documentation is available
from any authorized ENERVEX representative. Accessories,
fans, and variable frequency drives are not covered by
this manual. Please refer to these component’s individual

manuals.

TO REDUCE THE RISK OF FIRE,
ELECTRICAL SHOCK OR INJURY TO
PERSONS, OBSERVE THE FOLLOWING:

1. Use this unit in the manner intended by the manufacturer.
If you have questions, contact the manufacturer at the
address or telephone number listed on the front of the
manual.

2. Before servicing or cleaning the unit, switch off at service
panel and lock service panel to prevent power from being
switched on accidentally.

3. Installation work and electrical wiring must be done by a
qualified person(s) in accordance with applicable codes
and standards.

4. Follow the appliance manufacturer’s guidelines and safety
standards such as those published by the National Fire
Protection Association (NFPA), and the American Society
for Heating, Refrigeration and Air Conditioning Engineers
(ASHRAE), and the local code authorities.

5. This unit must be grounded.

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Content

1. PRODUCT INFORMATION

1.1 Function ................................................................. 4

1.2 Shipping ................................................................ 4

1.3 Warranty ................................................................ 4

2. SPECIFICATIONS AND DIMENSIONS

2.1 Dimensions and Capacities .................................... 5

3. MECHANICAL INSTALLATION

3.1 Location................................................................. 6

3.2 Mounting of Control ............................................... 6

3.3 Mounting of Transducer ......................................... 7

3.4 Mounting of Duct Probe ......................................... 7

3.5 Connecting Transducer to Duct Probe ................... 7

4. ELECTRICAL INSTALLATION

4.1 General .................................................................. 8

4.2 Continuous Fan Operation ..................................... 9

4.3 Intermittent Fan Operation .......................................... 10

4.4 Connection to a Variable Frequency Drive ..................12

4.5 Integrated with External PDS ...................................... 13

5. STARTUP AND CONFIGURATION

5.1 General .................................................................. 14

5.2 Setting Operatuing Pressure .................................. 15

6. MAINTENANCE AND TROUBLESHOOTING

6.1 Troubleshooting ..................................................... 16

3916010 06.16

3

3916010 06.16

1. PRODUCT INFORMATION

1.1 FUNCTION

The ENERVEX MEC 18 is a Mechanical Exhaust Control used to
monitor and maintain a constant pressure in a duct system. This is
achieved by modulating the speed of a fan or ventilator. The MEC
18 can be used with ENERVEX Models EFH, RSV, BESB and BESF.
It can control the fan speed directly or via a Variable Frequency Drive
(VFD). It is a component in the MDVS, Mechanical Dryer Venting

TM

System

The MEC 18 is typically used to control the pressure in duct
systems serving clothes dryers, bathrooms, kitchen hoods and
other building venting applications.
The control monitors the pressure in a duct system via connection

to a pressure sensor (XTP2) , and maintains the pressure by
modulating the fan speed.

The control has an integrated safety system that assures the
appliance shuts down in the event of fan and/or control failure.

The use of the MEC 18 is not restricted to any type of duct or
venting application. When the appliance is activated, the control

sends maximum voltage to the fan or VFD. Once the specified
pressure is achieved, the control regulates the voltage to the fan or
VFD to manintain the specified pressure (the value can be viewed on
the display).

If desired, the control can be interlocked with an appliance. When
the appliance is activated, the control sends maximum voltage to

the fan or VFD. Once the specified pressure is achieved, the control
releases the appliance for operation and continues to regulate the
voltage to the fan or VFD to maintain the specified pressure (the
value can be viewed in the display). In the event of insufficient
pressure, the control assures the appliance(s) shuts down after 15
seconds. When the appliance shuts down, the control turns off the
fan.

The control can be used in one of two ways:

• Interlocked with the appliance to pre-purge the duct prior to
appliance start-up and post-purge the duct for 3 minutes after
appliance shut down, or,

• Set to run the fan continuously.

In most cases, local codes will require continuous fan operation.

The control has an integrated safety function. It can be operated
with a manual reset function (reset button) or an automatic reset
function. All terminal connections are monitored by LED’s for easy
service and troubleshooting.

ENERVEX’s MEC 18 is tested and listed to the Standard for Indus­trial Control Equipment, UL Standard 508, 16th Ed. and CSA C22.2
No. 14-95 as well as UL378, Standard for Pressure Equipment. It is
also tested and listed as a part of an ETL listed MDVS System (ETL
Report J99*18091-004) for exhausting of lint-laden air from single or
multiple type I and type II residential and commercial clothes dryers
whether electric or gas-fired.

and the MBES, Modulating Building Exhaust SystemTM.

1.2 SHIPPING

Standard packing list

The MEC 18 contains the following:

• MEC 18 control unit

• Pressure transducer (XTP)

• Silicone tubing

• Duct probe

• Jumpers
If other components are shipped, these will appear as separate

items on the shipment packing list.

1.3 WARRANTY

2-Year Factory Warranty. Complete warranty conditions are
available from ENERVEX, Inc.

4

2. SPECIFICATIONS

2.1 DIMENSIONS AND CAPACITIES

Specifications

MEC 18 Control

Power supply V 1x120VAC

Amperage A 6.3

Operating temperature °F/°C -4 to 122 / -20 to 50

Range of operation inWC / Pa 0-0.6 / 0-150

Tolerance inWC / Pa 0.01 / 3 +/-10%

Output Current mA max. 10

Max. Load 120 VAC / 8A

Real-time PID Control Method Infinitely variable

Real-time PID Signal Stability +/- 0.5%

Ramp Up/Down Time Seconds max 20

Output VAC 10-120

VDC 0-10

Dimensions A in / mm 7.17 / 182

B in / mm 7.09 / 180

C in / mm 4.37 / 111

Weight lbs/kg 3.0 / 1.5

EMC standard Emission EN50 081-1

Immunity EN50 082-2

XTP Sensor

Power supply VDC 12-36

Amperage mA <20

Output VDC 0-10

Operating temperature °F / °C 0 to 160 / -18 to 71

Accuracy +/- 0.08%

Dimensions D in / mm 3.70 / 94

E in / mm 5.12 / 130

F in / mm 6.18 / 157

G in / mm 3.13 / 80

Weight lbs / kg .6 / .3

Stack Probe

Dimensions H in / mm 4.25 / 108

I in / mm 3.50 / 89

3916010 06.16

MEC 18

FB

E

C

D

A

I

Symbols:

Fig. 1-A Fuse holder
Fig. 1-B Alarm-red LED
Fig. 1-C Reset button
Fig. 1-D Set point button
Fig. 1-E Potentiometer for pressure

setting
Fig. 1-F Display
Fig. 1-G LEDs (yellow) showing

increasing/decreasing speed
Fig. 1-H Dipswitch block
Fig. 1-I LEDs (green) showing ON/OFF

status

H

G

MEC 18

EXHAUST CONTROL

>

__

+24V

+24V

COM-0

COM

+24V-+

0-10V-

+0-10V

5

3916010 06.16

3. MECHANICAL INSTALLATION

3.1 LOCATION

The control and transducer must be installed indoors. The
control does not need to be installed in an enclosure. See
Fig. 2 for component connections.

The transducer cannot be mounted inside an
airtight enclosure. It uses the atmoshpheric
pressure as reference pressure.

XTP Sensor

3.2 MOUNTING OF CONTROL

The control can be mounted directly to a wall or similar.
Remove the cover. The mounting holes are located under the
plastic screws that hold the cover in place. See Fig. 3.

The distance between the control and the transducer should
not exceed three hundred (300) feet.

Max. 300 feet

Fig. 2

Fig. 2a

MEC 18

EXHAUST CONTROL

Fig. 3

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