VA Series Vapor Actuated Dial Thermometer
Vapor actuated thermometers give excellent readings when the bulb
temperature is either above or below the temperature of the indicating
head. Avoid applications in which the bulb and head are the same
temperature (ambient applications). If the bulb “crosses ambient” (i.e.,
goes from hotter than the indicating head to cooler or vice versa), some
pointer fluctuations will occur for up to two minutes during this
transition.
Recalibration
The VA Series vapor actuated thermometers are manufactured with
threaded, press fit and snap-ring lenses which can be easily removed
for field calibration.
To recalibrate your vapor actuated thermometer:
1. Remove the thermometer from its fitting.
2. Remove the lens.
4. Immerse the bulb totally in an agitated liquid for at least 3 minutes
with a master reference thermometer, until they reach equilibrium.
5. Use a wrench, coin or screwdriver to turn the slotted hex nut on the
back of the thermometer case until the pointer is at the proper
reading on the scale.
6. Replace the lens and reinstall the thermometer in its fitting.
Care of the Vapor Actuated Thermometer
• Avoid bending the stem, as this will result in frictional errors in
indication.
• Do not kink or flatten the capillary tube.
• Dampen any capillary vibration, as this may cause capillary breakage
over time.
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