ELECTRICAL

Figure 6.3: Wiring and Connection Diagram – Intermittent Ignition

2. Intermittent Ignition (see Figure 6.3 above)

a.The vent damper is continuously powered. On a call for heat, limit relay R is energized, which energizes:

the circulator (when used) through contact R1, and

the vent damper operator through contact R2, provided that the high-limit aquastat switch is closed.

The damper operator opens the vent damper.

b.Once the damper is proven open, the ignition circuit within the gas valve energizes, provided that all of the following conditions are met:

the blocked vent switch is closed, and

the flame rollout switch is closed.

c.When the call for heat ends:

Limit relay R de-energizes, which opens contacts R1 and R2.

The circulator shuts down.

The gas valve de-energizes.

The vent damper closes.

d.If temperature exceeds limit setting, main burners shut off and circulator continues to operate.

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PB Heat MI/MIH series manual Wiring and Connection Diagram Intermittent Ignition

MI/MIH series specifications

The PB Heat MI/MIH series represents a significant advancement in the realm of cast iron boilers, engineered for high efficiency and reliable performance in both residential and light commercial applications. Crafted with exceptional care, these boilers combine traditional design elements with modern technologies to optimize heating capabilities.

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