Sterling ME - Manual (Page 9)

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1. Mixed Air Controller
2. Return Firestat
3. Economizer
4. Filters
5. Blower Motor
6. Reverse Air Flow Switch
7. Clogged Filter Switch
8. High Voltage Barrier, Lamp
and Circuit Breaker Mount
9. Main Connection Board
with Fan Time Delay
and Function Relays
10. Power Venter Motor Assembly
(includes Relay and
Air Pressure Switch)
11. Junction Box/Ignitor
12. Time Delay Freezestat
13. Supply Firestat
14. Duct Thermostat
15. Primary Safety Limit
16. Gas Valve
17. High Limit Safety Switch
18. Transformer
19. Electrical Wiring Inlet
20. High Voltage Terminal Block
21. Door Safety Switch
22. Contactor
23. Centrifugal Blower
24. Damper Motor
25. Outside and Return Dampers
26. Ambient Lockout
Figure 8 - Make-Up Air Unit-Standard Blower Cabinet, Single Duct Furnace with Various Options Shown
[Power Vented ME Unit Shown]
Electronic: On units equipped with electronic modulating
control, follow control manufacturer’s installation
instructions for sensing of outlet air temperature.
*Also refer to the Indoor Duct Furnace Installation
Manual supplied with your unit.
ELECTRICAL CONNECTIONS
HAZARDOUS VOLTAGE!
DISCONNECT ALL ELECTRIC
POWER INCLUDING REMOTE
DISCONNECTS BEFORE
SERVICING. Failure to
disconnect power before
servicing can cause severe
personal injury or death.
All electrical connections must conform to: ANSI/NFPA
No. 70-1996 (or latest edition) National Electrical Code
and applicable local codes. In Canada, to the Canadian
Electrical Code, Part I CSA Standard C22.1.
The Make-Up Air packaged unit is wired at the factory
and ready to be connected. Actual unit wiring will differ
according to the options chosen. Each unit is shipped
with its own wiring diagram; refer to this wiring diagram
for all electrical connections to the unit.
All electrical connections, line voltage and thermostat,
are made in the Electrical Cabinet (See Figure 8). Line
voltage connections are made at the High Voltage
Terminal Block. Thermostat connections are made at the
Main Connection Board (See Figure 9).
Do not use any tools (i.e. screwdriver,
pliers, etc.) across terminals to check for power. Use
of a voltmeter is recommended.
Locate the thermostat in accordance with the instructions
supplied with the thermostat. All fi eld wiring must have
a minimum temperature rating of 85°C (185°F). Control
wiring shall be a minimum of 18 gauge wire size. Control
wiring must be sized for length of run.
Locate line voltage disconnect box per local codes. If
mounting the disconnect box to the unit, never mount
it to a unit access panel. Possible locations include
the front of the blower or fi lter section (See Figure 10).
Electrical conduit must be routed so as not to interfere
with removal of any access panel.
NOTICE: Should any original wire supplied with the
unit have to be replaced, it must be replaced with
wiring having a temperature rating of at least 105°C
(221°F).