Sterling MS User Manual
For heating, cooling and ventilating systems

MSIOM-3
J30-06624
INSTALLATION AND SERVICE MANUAL
SEPARATED COMBUSTION
INDOOR MAKE-UP AIR UNIT ARRANGEMENTS
FOR HEATING, COOLING AND VENTILATING SYSTEMS
Model No.______________________________________________ Serial No. ________________________
Improper installation, adjustment, alteration, service or maintenance can
cause property damage, injury or death. This appliance must be installed by a licensed 
contractor or qualified service personnel. Read these installation, operating and 
maintenance instructions thoroughly before installing or servicing this equipment. 
APPROVED FOR USE IN CALIFORNIA
INSTALLER’S RESPONSIBILITY
Installer Please Note: This equipment has been test fi red and inspected. It has been shipped 
free from defects from our factory. However, during shipment and installation, problems such 
as loose wires, leaks or loose fasteners may occur. It is the installer’s responsibility to 
inspect and correct any problems that may be found.
RECEIVING INSTRUCTIONS
Inspect shipment immediately when 
received to determine if any damage 
has occurred to the unit during 
shipment. After the unit has been 
uncrated, check for any visible 
damage to the unit. If any damage 
is found, the consignee should sign 
the bill of lading indicating such 
damage and immediately file claim 
for damage with the transpor tation 
company.
IMPORTANT: Look in direction of unit air fl ow to determine 
whether unit is right hand or left hand accessible.
12/12
Install, operate and maintain unit in accordance with manufacturer’s
instructions to avoid exposure to fuel substances or substances from incomplete 
combustion which can cause death or serious illness. The state of California has 
determined that these substances may cause cancer, birth defects, or other reproductive 
harm. Install and Service this product to avoid exposure to airborne particles of 
glasswool fi bers and/or ceramic fi bers known to the State of California to cause cancer 
through inhalation.
ATTENTION: READ THIS MANUAL, SEPARATED COMBUSTION INDOOR DUCT FURNACE SCDFM MANUAL (EVAPORATIVE 
OR COOLING COIL MANUALS IF APPLICABLE), UNIT SUBMITTAL DATA SHEETS AND ALL LABELS ATTACHED TO THE 
UNIT CAREFULLY BEFORE ATTEMPTING TO INSTALL, OPERATE OR SERVICE THESE UNITS! CHECK UNIT DATA PLATES 
FOR TYPE OF GAS AND ELECTRICAL SPECIFICATIONS AND MAKE CERTAIN THAT THESE AGREE WITH THOSE AT THE 
POINT OF INSTALLATION. RECORD THE UNIT MODEL NUMBER AND SERIAL NO.(S) IN THE SPACE PROVIDED. RETAIN 
THIS DOCUMENT FOR FUTURE REFERENCE.
260 NORTH ELM ST., WESTFIELD, MA 01085
TEL: (413) 568-9571 FAX: (413) 562-8437
www.mestek.com
FOR YOUR SAFETY
If you smell gas: 
1. Open windows.
2. Don’t touch electrical switches. 
3. Extinguish any open fl ames. 
4. Immediately call your gas supplier.
FOR YOUR SAFETY
The use or storage of gasoline or other 
flammable vapors or liquids in open 
containers in the vicinity of this appliance 
is hazardous. 
