Gas PipingQuestion 247 of 360
Low gas pressures for appliances are commonly expressed in inches of water column. Which instrument directly reads this pressure during setup and testing?
a.A megohmmeter
b.A manometer (water column or digital)
c.An amp clamp
d.A pyrometer
Explanation
A manometer, either a U-tube filled with water or a digital equivalent, directly measures the low gas pressures used by appliances in inches of water column. It is the standard tool for checking supply pressure and manifold pressure. A megohmmeter, amp clamp, and pyrometer measure electrical resistance, current, and temperature instead.
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