EMI T3HB, T4HB, T2HB, S2HB manual Piston/Orifice Change Kit Installation

Multi-Zone Heat Pump Refrigerant Piping Installation

NOTE: Refrigerant Piping Installation for all of the multi-zone heat pump models.

Interconnecting Tubing Specs

S2HB, T2HB, T3HB, & T4HB models:

Nominal	Maximum	Maximum	Liquid	Suction
Circuit			Line	Line
	Length	Lift
Capacity			OD	OD
9,000	100’	35’	1/4”	1/2”
12,000	100’	35’	1/4”	1/2”
18,000	100’	35’	3/8”	5/8”*
24,000	100’	35’	3/8”	3/4”

*CAH24, UNH24, WLH24 Suction Connection size is 3/4” O.D. and must bush down to 5/8” for 18,000 Btuh circuits at the indoor unit.

The system will support refrigerant runs to the inside unit of up to 100' equivalent feet with a 35' rise included. The units are furnished with sweat connections and are equipped with refrigerant valves and

Schrader fittings for charging and taking pressure readings. The following precau- tions should be made:

•Be certain no burrs remain on the fittings.

•Use only clean refrigeration tubing.

•Use tube benders to guard against kinking.

•Avoid piping on wet and rainy days and insulate suction line. Be certain that plastic end caps remain in place when inserting through wall openings. Isolate tubing from transmitting vibra- tion to the building or unit and avoid contact with sharp edges. Refrigera- tion valves should be wrapped with a wet rag "heat sink" to protect valves while brazing.

Piston/Orifice Change Kit Installation

When a WLH24 or UNH24 air handler is matched with a T2HB or T3HB contain- ing a 24,000 Btuh nominal capacity circuit, the air handler must have it’s stock piston changed from 0.059 to 0.063.

Air Handler

A 24,000 Btuh nominal circuit can be identified by the “4” in the model number capacity field (i.e.

T2HBx4xx). Refer to the instructions sup- plied with kit part number; 240006777.

Circuit Designators: 9 = 9000 Btuh • 2 = 12000 Btuh • 8 = 18000 Btuh • 4 = 24000 Btuh (ex. - 8400 consists of one 18000 Btuh compressor and one 24000 Btuh compressor)

Model #

Air Handler

Condenser

Btuh

Factory installed Piston/Orifice Size

Field Changeover

Piston/Orifice Size

WLH24

or

UNH24

T2HB2400 T2HB8400 T2HB4400 T3HB9940 T3HB9240 T3HB2240

.059”

.063”

Note: this kit is only supplied with the above Heat Pump models.

Multi-zone Heat Pump Condensing Units 9 www.enviromaster.com