28
MCP15-500.9
START-UP PROCEDURE - CONTINUED
Figure 28.1 - Gas Heat Option Gas Controls - D-Cabinet Sized Units - 800,000 Btu/hr and Smaller (81% Eff)
1.
Power exhauster
2.
Maxitrol EXA STAR modulating gas valve (primary furnace only)
3.
Main combination gas valve
4.
High limit control (hidden behind piping as shown)
5.
Solid state ignition control board (cover removed)
6.
Furnace control board (cover removed)
7.
Vent differential pressure proving switch
8.
Direct spark ignitor
9.
Manifold pressure tap on manifold tee (primary furnace only)
10.
Flame sensor
11.
Manifold piping with gas orifices
12.
Heat exchanger tube drain tray with drain line
1
3
5
7
2
4
6
8
10
11
12
9
Primary Furnace (Right
Side of
Cabinet)
Secondary Furnace (Left Side of
Cabinet)
1
3
5
7
4
6
8
10
11
12
