Pipework Arrangement - York YMAA 0045 Installation Manual

Air-cooled chiller and heat pump 50hz 44-255kw

Table of Contents

FORM NO.: 6U6K-B01E-NB-EN

Consideration should be given to compressor and control panel

access when laying out water piping. Routing the water piping

too close to the unit could make compressor/ control panel

servicing/ replacement difficult.

Hand stop valves should be installed in all lines to facilitate

servicing.

Piping to the inlet and outlet connections of the

unit should include high-pressure rubber hose or

piping loops to ensure against transmission of water

pump vibration. The necessary components must be

obtained in the field.

Drain connections should be provided at all low points to permit

complete drainage of the cooler and system water piping.

A small valve or valves should be installed at the highest point

or points in the chilled water piping to allow any trapped air

to be purged. Vent and drain connections should be extended

beyond the insulation to make them accessible.

The piping to and from the cooler must be designed to suit

the individual installation. It is important that the following

considerations be observed:

1.The chilled liquid piping system should be laid out so that the

circulating pump discharges directly into the cooler. The suction

for this pump should be taken from the piping system return

line and not the cooler. This piping scheme is recommended,

but is not mandatory.

2.Standard pipework connections are victaulic connections.

The inlet and outlet cooler connection sizes are 2" (YMAA/

YMPA 0045-0065), 2-1/2" (YMAA/YMPA 0080-0130) and 4"

(YMAA/YMPA 0160-0260) .

3.A strainer is integrated in the cooler inlet line just ahead of

the cooler. This is important to protect the cooler from entrance

of large particles which could cause damage to the evaporator.

4.All chilled liquid piping should be thoroughly flushed to

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free it from foreign material before the system is placed into

operation. Use care not to flush any foreign material into or

through the cooler. It is recommended that a suitably sized by-

pass and valve arrangement be installed to allow flushing of the

pipework system. The by-pass can be used during maintenance

to isolate the cooler without disrupting flow to other units.

5.As an aid to servicing, thermometers and pressure gauges

should be installed in the inlet and outlet water lines.

6.The chilled water lines that are exposed to outdoor ambient

should be wrapped with supplemental heater cable and insulated

to protect against freeze-up during low ambient periods, and to

pre- vent formation of condensation on lines in warm humid

locations.

7.The cooler is protected by heater mats placed under the

insulation, which are powered from the unit control system

power supply. During cold weather when there is a risk of

freezing, unit power should be left switched on to provide the

freeze protection function unless the liquid systems have been

drained.

8.A chilled water flow switch is already installed in the leaving

water piping of the cooler. If the units are modularized, it is

recommended to install another flow switch in main liquid

leaving pipe. There should be a straight horizontal run of at

least 5 diameters on each side of the switch. Adjust the flow

switch paddle to the size of the pipe in which it is to be installed

(see manufacturer's instructions furnished with the switch).