Raypak 133-4001 manual Limit Controls, Manual-ResetHigh Limit, Auto-ResetHigh Limit, Flow Switch

Fig. 31: 2-Stage Tankstat

Limit Controls

Manual-Reset High Limit

All models except 133 are equipped with a manual reset high limit. Set the manual limit to its maximum set point.

Fig. 32: Manual Reset High Limit

Auto-Reset High Limit

Set the auto limit(s) to 30-40 °F above the desired operating temperature and 5-10°F below the Manual High Limit setting.

Flow Switch

This dual purpose control shuts off the boiler in the case of a pump failure or low water condition. It is mounted and wired in series to the main gas valve. Standard on all models except the 133.

NOTE: Flow switch will not operate if flow is less than 12 gpm.

Fig. 33: Flow Switch

100% Pilot Safety

All standard boiler models 181-4001 employ electron- ic devices which close 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 pow- ered. Unit performs its own safety check and opens the main valve only after the pilot is proven to be lit.

Fig. 34: Safety Control

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