Carrier 30XA080-500 specifications A30-4415, PT Hydronic Pump Package

INSIDE

UNIT

OUTSIDE

UNIT

LEGEND

D— Drain,3/4-in. NPT D′ — Drain, 1/4-in. NPT

E— Expansion Tank Connection, 3/4-in. NPT FS — Flow Switch

PP— Pipe Plug, 1/4-in. NPT

PT — Pressure/Temperature Tap T1 — Leaving Water Thermistor T2 — Entering Water Thermistor

V— Vent, 1/4-in. NPT

*Field-supplied and installed. †Factory-installed option. **Required for open loop systems.

a30-4415

D	V	T1	PP
	Heater
		FS PP		T2

Chilled Water Out

PT HYDRONIC PUMP PACKAGE

D

PT
D	PT
PT	E	PT
		D
		Heater

Chilled

Water In

Pressure Relief*

Flexible Connections*

Pressure Reducing

Fill Valve*

Air Separator with Vent*

Strainer/Suction Guide

Reverse Flow Check Valve/Service Valve

Service Valve

Pump

Combination Valve

Isolation Valve*

20 Mesh Stainer**

Fig. 26 — Typical Piping Diagram on 30XA Units with Hydronic Package — Dual Pumps

NOTE: It is recommended for units with the hydronic package that an inlet isolation (shut-off) valve be placed exterior to the unit to allow removal and service of the entire pump assembly, if necessary. The hydronic package is supplied from the factory with a combination valve for isolation of leaving water. Also, if the unit is isolated with valves, a properly sized pressure relief valve is recommended and should be installed in the pip- ing between the unit and the valves, following all applicable local codes.

Air Separation — For proper system operation, it is essential that water loops be installed with proper means to manage air in the system. Free air in the system can cause noise, reduce terminal output, stop flow, or even cause pump failure due to pump cavitation. For closed systems, equipment should be provided to eliminate all air from the system.

The amount of air that water can hold in solution depends on the pressure and temperature of the water/air mixture. Air is less soluble at higher temperatures and at lower pressures. Therefore, separation can best be done at the point of highest water temperature and lowest pressure. Typically, this point would be on the suction side of the pump as the water is return- ing from the system or terminals. This is generally the optimal place to install an air separator, if possible.

1.Install automatic air vents at all high points in the system. (If the 30XA unit is located at the high point of the sys-

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tem, a vent can be installed on the piping leaving the heat exchanger on the 1/4 in. NPT female port.)

2.Install an air separator in the water loop, at the place where the water is at higher temperatures and lower pres- sures — usually in the chilled water return piping. On a primary-secondary system, the highest temperature water is normally in the secondary loop, close to the decoupler. Preference should be given to that point on the system (see Fig. 27). In-line or centrifugal air separators are read- ily available in the field.

It may not be possible to install air separators at the place of the highest temperature and lowest pressure. In such cases, preference should be given to the points of highest temperature. It is important that the pipe be sized correctly so that free air can be moved to the point of separation. Generally, a water velocity of at least 2 feet per second (0.6 m per second) will keep free air entrained and prevent it from forming air pockets.

Automatic vents should be installed at all physically elevated points in the system so that air can be eliminated during system operation. Provisions should also be made for manual venting during the water loop fill.

UNITS WITH HYDRONIC PUMP PACKAGE — The 30XA090-160 units can be equipped with a factory-installed hydronic pump package consisting of a suction guide/strainer, pump, combination valve, internal piping and wiring con- nected at the factory.