Carrier 50RHE006-060 specifications Typical Ground-WaterPiping Installation

Step 7 — Piping Connections — Depending on the application, there are 3 types of WSHP piping systems to choose from: water loop, ground-water and ground loop. Refer to Piping Section of Carrier System Design Manual for addi- tional information.

All WSHP units use low temperature soldered female pipe thread fittings for water connections to prevent annealing and out-of-round leak problems which are typically associated with high temperature brazed connections. Refer to Table 1 for connection sizes. When making piping connections, consider the following:

•Use a backup wrench when making screw connections to unit to prevent internal damage to piping.

•Insulation may be required on piping to avoid condensa- tion in the case where fluid in loop piping operates at temperatures below dew point of adjacent air.

•Piping systems that contain steel pipes or fittings may be subject to galvanic corrosion. Dielectric fittings should be used to isolate the steel parts of the system to avoid galvanic corrosion.

WATER LOOP APPLICATIONS — Water loop applications usually include a number of units plumbed to a common pip- ing system. Maintenance to any of these units can introduce air into the piping system. Therefore, air elimination equipment comprises a major portion of the mechanical room plumbing.

The flow rate is usually set between 0.040 and 0.054 l/s per kW of cooling capacity. For proper maintenance and servicing, pressure-temperature (P/T) ports are necessary for temperature and flow verification.

In addition to complying with any applicable codes, consid- er the following for system piping:

•Piping systems using water temperatures below 10 C require 12.7 mm closed cell insulation on all piping surfaces to eliminate condensation.

•Avoid all plastic to metal threaded fittings due to the potential to leak. Use a flange fitted substitute.

•Teflon tape thread sealant is recommended to minimize internal fouling of the heat exchanger.

•Use backup wrench. Do not overtighten connections.

•Route piping to avoid service access areas to unit.

•Flush the piping system prior to operation to remove dirt and foreign materials from the system.

GROUND-WATER APPLICATIONS — Typical ground- water piping is shown in Fig. 8. In addition to complying with any applicable codes, consider the following for sys- tem piping:

•Install shut-off valves for servicing.

•Install pressure-temperature plugs to measure flow and temperature.

•Connect boiler drains and other valves using a “T” con- nector to allow acid flushing for the heat exchanger.

•Do not overtighten connections.

•Route piping to avoid service access areas to unit.

•Use PVC SCH80 or copper piping material.

NOTE: PVC SCH40 should not be used due to system high pressure and temperature extremes.

Water Flow

Control Regulator

Valve

Boiler

Drains

Pressure-

Temperature

Plugs

Pressure

Tank

Water Out

Water In

From Pump

Shut-Off

Valve

Strainer – Field-Installed Accessory (16 to 20 mesh recommended for filter sediment)

Fig. 8 — Typical Ground-Water Piping Installation

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