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Profire E/LNE Series Manual
4-9
Adjustments
4.10 — Dual Manifold Systems
Certain models may use a dual-gas manifold for optimal gas/air mixing. These systems use two gas-metering-butterfly
valves to control the gas flow into their respective manifolds as shown in Figure 4-3. The Secondary valve controls the
low-to-mid-fire gas and the Primary valve controls the mid-to-high-fire gas.
4.10.1 — Gas Metering Valve Theory of Operation
Figure 4-4 provides the approximate valve-opening positions with respect to firing rate. The burner control may incre-
ment position in terms of percent open or degrees open but they are largely equivalent for the purposes of this setup
instruction.
FIGURE 4-3.
Dual Manifold
