Thomas & Betts RZ405, RGM 405 dimensions Optional Cased Cooling Coil, Model ACUA, ACUB, or Acuc

OPTIONAL ACCESSORIES

17. Optional Cased Cooling Coil, Model ACUA, ACUB, or ACUC

This cased cooling coil is designed for use with the Model CAUA upflow heater. It is shipped separately for field installation over the discharge opening of the heater. Before installing, verify that the coil cabinet is the same size as the heater cabinet.

Follow the installation instructions shipped with the cooling coil (Installation Form RZ 405-CC), the wiring diagram, and the instructions provided by the compressor manufacturer.

Model		ACUA				ACUB				ACUC
S i z e	060		072	090	090		120	150	120	150		180
Nominal Cooling Capacity (MBH)	60		7 2	9 0	9 0		120	150	120	150		180
Refrigerant Type	R-22		R-22	R-22	R-22		R-22	R-22	R-22	R-22	R-22
Thermal Expansion Valves*	1		1	1	1		2	2	2	2		2
Approximate Weight (lbs)	8 3		8 6	105	110		122	140	176	180		188
No. of Intertwining Circuits	8		8	1 2	1 2		1 2	1 8	1 2	1 6		1 8
Face Area (sq ft)	7.79		7.79	9.38	14.04		11.67	13.70	17.13	15.38	17.13
Rows-Fins/Inch	2-10		2-12	3-10	2-12		3-10	3-12	2-12	3-10		3-10
Airflow (cfm) Low		1800				3000				4000
Nominal		2400				4000				5000
High		3000**				5000**				6000**

* - TXV's are factory supplied. Models with two TXV's have intertwined circuiting.

** - Airflow in excess of maximum values shown may result in blow-off of condensation.

Heater/Coil Cross-Reference

Table by Cabinet Size

Heater Model CAUA

150	200	250	300	350	400
ACUA		ACUB		ACUC
060		090			120
072		120			150
090		150			180

Figure 19 - A Model ACU cooling coil installed on a Model CAUA heater and the line connection sizes

Suction Line
Connection(s)	ModelACU
Liquid Line
	Cased
Connection(s)	Cooling Coil
3/4" Drain Line
Connection
ModelCAUA
Heater

Hole for Burner Condensate Drain Tube (use this hole or the one on the opposite side) - see Paragraph 10, page 14

Model	S i z e	Connections
ACUA 060/072		(1) 7/8" Suction Line
	060	(1) 3/8" Liquid Line
	072	(1) 1/2" Liquid Line
	090	(2) 7/8" Suction Lines
	090	(2) 3/8" Liquid Lines
ACUB	090/120/150	(2) 7/8" Suction Lines
	090/120	(2) 3/8" Liquid Lines
	150	(2) 1/2" Liquid Lines
ACUC 120/150/180		(2) 7/8" Suction Lines
	120	(2) 3/8" Liquid Lines
	150/180	(2) 1/2" Liquid Lines

Drain line connection is 3/4" for all sizes.

Burner Condensate Drain

When a system includes a cooling coil, a burner condensate drain must be installed. The parts required for the drain are shipped with the heater. Instructions for installing the drain are in Paragraph 10, page 14.

Electrical Connections

Figure 20 - Typical

Heater Terminal Strip

Low Voltage Wiring (field-supplied)

Thermostat	24V Supply *
Connections
(Read thermostat
manufacturer’s	Common
installation
instructions
before wiring.)	1st Stage Cooling
	2nd Stage Cooling
	1st Stage Heating
	Optional 2-Stage Heating
	Fan

R

C

Y1

Y2

W1

W2

G

Condensing Unit Connections (Read

Common manufacturer’s installation instructions before wiring.)

1st stage cooling 24V control relay

2nd stage cooling 24V control relay for Sizes 090, 120, 150, and 180

* A separate 24V control transformer may	Legend (field-supplied 24V wiring)
be required for the condensing equipment controls
Install a jumper wire between RH and RC terminals		Thermostat wiring - 24V
on the thermostat for single transformer operation.
		Field control wiring - 24V
Consult the thermostat manufacturer’s instructions.
		Mfg No. 164771, Page 19