AHRI OM 210, Руководство по эксплуатации

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USE OM - JANUARY 2017
71
7.2.2
Outdoor air inlet temperatures shall be measured with RTD using sampling device per the latest edition
of ASHRAE Standard 41.1 and 41.6.
7.2.2.1
All air inlet temperature measurements shall be taken using a sampling tree.
7.2.2.2
Sampling trees shall cover at least ¾ of the inlet area of each face, and no air shall be
sampled outside of the inlet face area.
7.2.3
Outdoor air outlet temperatures, when duct is connected, shall be measured with an RTD using a
sampling device per the latest edition of ASHRAE Standard 41.1 and 41.6.
7.2.4
When thermocouples (TC) are used for measurement of refrigerant temperature by application to the
outside of tubing, the following requirements shall be met:
7.2.4.1
The TC material used shall have special limits of error of 0.75°F or less.
7.2.4.2
For non-vertical tubes, the TCs shall be placed in the upper half of refrigerant tubes,
as there may be oil in the lower half.
7.2.4.3
At the indoor coil, two TCs shall be applied within three (3) inches of each other, with
one TC at the
10 o’clock position and one TC at the 2 o’clock position (for each liquid and vapor line,
total of four TCs). Each TC shall be measured individually. Average of the two temperatures on each
liquid and vapor line shall be used for calculations.
7.2.4.4
Each and every TC shall be applied to the tubes per ASHRAE Standard 41.1 Section
10.
7.2.4.4.1 There shall be no more than 3 turns of wires contacting each other.
7.2.4.4.2
The wires shall be
‘tinned’ or soldered together before application to the
tube.
7.2.4.4.3
The wires shall be secured to the tube via soldering or welding (without
burning insulation or melting wire).
7.2.4.4.4
The wires outside of the joint described in Section 7.2.4.4.3 shall be
prevented from touching each other or other metallic surfaces, preferably by applying
electrical tape between the wire and the tube outside of the solder bed.
7.2.4.5 Each and every TC shall be applied per ASHRAE Standard 41.1 Section 8.2, having
insulation with an R-value of at least 3.1, extending along the tube for at least six (6) inches on either
side of the TC. This requirement for 6” is not applicable to TCs applied to coil surfaces such as return
bends used for determining refrigerant saturation temperature.
7.2.5
TCs may be applied at to the condenser coil tubing halfway between the vapor connection and the
liquid connection of the individual circuit, in two (2) separate locations, in order to determine saturation temperature
a midpoint of the circuit.
7.3 Fan Motor Properties
7.3.1
Fan speed measurements, when measured, shall be taken with an instrument accurate to ± 1 rpm.
7.3.2
Fan amps, when measured, shall be taken with an ammeter having an accuracy of 2.0%, or better, of
the fan motor current being measured.