Raypak 751 manual Ignition Control Module, Flow Switch, High Limit - Manual Reset

Ignition Control Module

The intermittent ignition device conserves energy by automatically extinguishing the pilot when the desired temperature is reached. When additional heat is need- ed, the combustion air blower starts to purge all air from the combustion chamber for about 45 seconds. On proof of air flow, the air proving switch closes and the pilot reignites electrically, eliminating the fuel costs of maintaining a constant pilot.

To ensure safe operation, the gas valve cannot open until the pilot relights and is verified. The 100% pilot safety is an electronic device which closes the main gas valve within 8/10 of a second whenever the pilot flame is interrupted. Pilot flame is automatically lit when the device is powered and pre-purged. Unit per- forms its own safety check and opens the main valve only after the pilot is proven to be lit.

Flow Switch

Dual-purpose control shuts off boiler in case of pump failure or low water condition. Mounted and wired in series with the main gas valve. Check with the manu- facturer for proper paddle size. Utilize correct paddle size for proper operation.

NOTE: Flow switch will not operate if flow is less than 20 gpm.

Fig. 31: Ignition Module

High Limit — Manual Reset

This appliance is equipped with a manual reset, high limit, safety device. Push the reset button and adjust the setting to 40°F above the desired operating tem- perature.

Fig. 33: Flow Switch

High Limit — Auto Reset

This appliance is equipped with an automatic, high limit, safety device. Set the auto high limit to 30°F above the desired operating temperature.

Fig. 34: Auto Reset — High Limit

Fig. 32: High Limit — Manual Reset

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