Liquid level and temperature monitoring apparatus

An apparatus for use in monitoring the level and temperature of a liquid flowing through a horizontally extending line formed by first and second line sections, wherein the temperature of the liquid is to be maintained below an established acceptable value, the liquid level and temperature monitoring apparatus comprising:

• a chamber interposed between the first and second line sections and including a transverse cross-sectional area greater than the transverse cross-sectional area of the liquid line, the chamber being disposed at least partially above the line and being normally closed except for an inlet in fluid communication with the first line section and an outlet in fluid communication with the second line section;
• a temperature sensor provided within the chamber above the height of the line;
• an alarm;
• a control means connected between the temperature sensor and the alarm for measuring the temperature of the sensor and activating the alarm when the sensor temperature exceeds a predetermined value above the established acceptable value;
• a heater provided within the chamber adjacent the temperature sensor above the height of the line, the heater being of a temperature greater than the predetermined value so that when the liquid within the chamber falls below the temperature sensor and heater, heat is transferred to the sensor and raises the temperature of the sensor, and when the liquid level within the chamber reaches the sensor and heater, heat is transferred to the liquid and the temperature of the sensor is maintained at about the same value as the liquid;
• and
• an air removal means disposed within the chamber above the height of the line for relieving trapped air from the chamber so that the trapped air does not force the liquid level below the temperature sensor,
• the air removal means including a capillary tube having opposed first and second ends, wherein the first end is disposed within the outlet and extends into the line in the direction of fluid flow so that a negative pressure is exerted at the first end, and the second end is disposed within the chamber at a height at least equal to the height of the sensing means so that air adjacent the sensing means is drawn through the tube from the chamber and introduced back into the liquid.