York YCUL0045E, Установка, эксплуатация и обслуживание

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JOHNSON CONTROLS
22
FORM 150.63-NM8 (1020)
INSTALLATION
REFRIGERANT PIPING NOTES
1. Based on R-22 at the nominal capacity of the unit or system, an ambient temperature of 95°F (35°C) and a suc -
tion temperature of 45°F (7.2 °C).
2. Suction line sizes were calculated based on a nominal maximum pressure drop of 3 PSI/100 ft. (20.7kPa30.5m).
When calculating suction line pressure drop for a specific application, it should be noted that system capacity
decreases as suction line pressure drop increases.
3. Liquid pressure drop (or gain) due to a vertical liquid line is not included in the tables and must be taken into ac-
count when determining pressure drop (or gain) of the liquid line. The nominal value that must be included in the
liquid line loss (or gain) is .5 PSI/foot (3.4 kPa/30 cm) of rise (or gain). To ensure a solid column of liquid refrigerant
to the expansion valve, the total maximum pressure drop of the liquid line should not exceed 40 PSI (276 kPa)
based on 15°F (8.3 °C) subcooled liquid. Vapor in the liquid line, even in small amounts, will measurably reduce
valve capacity and poor system performance will result. In addition, pressure loss for strainers, filter driers, sole -
noid valves, and isolation valve or fittings are not included in this table, and must be taken into account.
4. Nominal Tons (KW) Unloaded is based on one compressor (per system) operating at design conditions.
5. Based on minimum compressor staging for the given pipe size, a double suction riser should be used to ensure
proper oil return to the compressor on all vertical suction risers. Oil returning up the riser moves up the inner
surface of the pipe and depends on the mass velocity of the refrigerant vapor at the wall surface to move the oil
up the vertical rise
6. Hot gas bypass lines are typically 7/8" for lines up to 40 feet and 1-1/8" for lines over 40 feet (12 meters) in length.
The field connections sizes are 7/8" for the optional factory mounted hot gas bypass valve.
7. For more information, please refer to either the York DX Piping Application Guide or the ASHRAE Refrigeration
Handbook.
Hot gas bypass is only available
for refrigerant system number 1.