shall be permitted on new hot water piping for on-off operation, and for
existing hot water piping sizes not greater than 80 mm 3 inches. Clean the
pipe to bright metal. Insulate strap-on bulb and pipe after installation.
Provide other liquid temperature sensors with thermowells. Provide NEMA 250
Type 4 enclosures for outdoor installations. Provide brushed aluminum or
brushed stainless steel enclosures for sensors located in finished spaces.
3.1.1.5
Outside Air Temperature Sensors
Provide outside air temperature sensor on north side of building, away from
exhaust hoods, air intakes, and other areas which may affect temperature
readings. Install sunshields to protect outside air temperature sensor
from direct sunlight.
3.1.1.6
Low-Temperature Protection Thermostats (Freezestats)
Provide thermostat for each [7.5 square meter] [80 square feet] [_____] of
coil-face area to sense the temperature at location indicated. Install
thermostat sensing element in serpentine pattern.
3.1.2
Thermometers
Provide thermometers which are installed in liquid systems in thermowells
with thermal transmitting materials within the well to speed the response
of temperature measurement.
3.1.3
Pressure Sensors
3.1.3.1
Duct Static Pressure
Duct static pressure sensor shall be located where indicated on drawings.
If no location is indicated, it should be located approximately two-thirds
of distance from supply fan to the end of duct with greatest pressure drop.
3.1.3.2
Steam Pressure
Provide snubbers and isolation valves on steam pressure sensing
applications.
3.1.4
Pressure Gages
Provide snubbers for gages in piping systems subject to pulsation. Gages
for steam service shall have pigtail fittings with cocks. Install pressure
gages at locations indicated. Pneumatic output lines shall have pressure
gages mounted near the control panel.
3.1.5
Valves
Provide valve with stems upright where possible but with stems not lower
than horizontal. Provide positioners where indicated and where necessary
to prevent overlap of heating and cooling where one controller operates
more than one pneumatic device and to maintain the proper dead band between
heating and cooling.
3.1.6
Damper Actuators
Provide damper actuators so that the damper sealing action is smooth and
sufficient to maintain leakage at or below specified leakage rate.
Multiple actuators operating a common damper shall be connected to a common
SECTION 15901N
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