background image

66-1142—1    G.R.  Rev. 03-04 

www.honeywell.com

MCBA14C COMMERCIAL BOILER CONTROL SYSTEM

Automation and Control Solutions

Honeywell International Inc.

Honeywell Limited-Honeywell Limitée

1985 Douglas Drive North

35 Dynamic Drive

Golden Valley, MN  55422

Scarborough, Ontario
M1V 4Z9

Printed in U.S.A. on recycled 
paper containing at least 10% 
post-consumer paper fibers.

3.

Check the ratings given in the instructions and on the 

product to make sure that the product is suitable for your 

application.

4.

Installer must be a trained, experienced combustion 

service technician.

5.

Disconnect the power supply before beginning installation 

to prevent electrical shock and equipment damage. More 

than one disconnect may be involved.

6.

All wiring must comply with applicable local electrical 

codes, ordinances and regulations.

7.

After installation is complete, check out product operation 

as provided in these instructions.

WARNING

Fire or Explosion Hazard.

Can cause severe injury, death, or property damage.

To prevent possible hazardous burner operation, verify 

safety requirements each time a control is installed on a 

burner.

WARNING

Electrical Shock Hazard.

Can cause serious injury, death or property damage.

Disconnect power supply before beginning installation to 

prevent electrical shock and equipment damage. More 

than one disconnect may be involved.

WIRING

WARNING

Electrical Shock Hazard.

Can cause serious injury, death or property damage.

Disconnect power supply before beginning wiring to 

prevent electrical shock and equipment damage. More 

than one disconnect may be involved.

Ground Connection

The ground connection on the controller must not be used as a 

central ground connection for the 120 Vac connections. 

1.

Use the common ground terminal next to the controller, 

close to connector X1. 

2.

Connect the central ground terminal with the connection 

contact of the controller.

3.

Connect the ground wire of the main power connector, the 

CH pump, the DHW pump (if present) and the ignition wire 

to the central ground terminal.

Electrical Connections

Main Power Line

1.

Hot (L1) to connector X1-L.

2.

Neutral (L2) to connector X1-N.

3.

Ground to central ground terminal, not to Ground on X1.

CH Pump; DHW Pump Power Line(s)

1.

Hot to connector X1-4 (CH Pump) or X1-5 (DHW Pump).

2.

Neutral to connector X1-3.

3.

Ground to central ground terminal, not to Ground on X1.

Low Voltage Connections

Use 18 AWG or larger wires.

1.

Wire according to specifications, following all local ordi-

nances and requirements.

2.

Do not bundle the low voltage wires with the ignition cable, 

120 Vac wires, CH Pump or DHW Pump.

3.

The low voltage wires for the minimal gas pressure switch, 

DHW thermostat, air pressure switch, and gas valve can be 

bundled together.

4.

Bundle the wires for the fan and join them with the other 

24V low-voltage wires.

5.

Bundle the wires for the NTC sensors and the PWM pump 

control separately.

6.

Do not bundle the ionization wire with the high voltage 

cables, but it can be joined with the other 24V wires.

High Voltage Cable

1.

Always use a grommet when placing the high voltage 

cable.

2.

Never join the high voltage cable with other wires.

Reviews: