A. O. Smith RXLD-28 User Manual

®

Residential Heating

CIRCULATING LOOP HEAT EXCHANGERS

The ProMax® XL circulating loop heat exchanger is designed specifically for
installation with A.O. Smith ProMax® SL (Side Loop) gas water heaters.
The combination of a ProMax SL water heater and ProMax XL heat exchanger
provides domestic hot water, and an isolated source of hot water for radiant
floor heating, hydronic air handlers and other closed loop applications.

OUTPUT OPTIONS

■ 28,000 BTU (RXLD-28 and RXLS-28)

■ 52,000 BTU (RXLD-52 and RXLS-52)

COMPACT, EFFICIENT, BRAZED PLATE HEAT EXCHANGER

■ UP TO 60% smaller than traditional shell & tube and coaxial heat exchangers

SINGLE OR DOUBLE-WALL DESIGN

■ Double-wall construction for applications requiring double isolation between fluid streams

AUXILIARY CONNECTIONS EXPAND OPTIONS

■ Plugged connections can be used as installation points for thermowells, a drain or for flushing

heat exchanger

■ Connections located on front of heat exchanger, common to primary side of heat exchanger

115V/60Hz PUMP

■ Control relay (24 volt coil) located inside wiring junction box

PROMAX SL GAS WATER HEATER OPTIONS

■ Standard Vent

■ Direct Vent

■ Power Vent

■ Power Direct-Vent

STANDARDS

■ All components UL Listed

1-YEAR LIMITED WARRANTY

■ For complete information, consult written warranty or contact A.O. Smith Water Heaters

June 2010R

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AOSRG46600

ARGSS00307

®

Residential Heating

CIRCULATING LOOP HEAT EXCHANGERS

COIL & AIR HANDLER APPLICATION - HEAT EXCHANGER SELECTION TABLE

0

140

F SOURCE (TANK)

0

F SOURCE (TANK)

150

0

160

F SOURCE (TANK)

BTUH GPM

30,000 3.0 1.1

55,000

36,000

60,000

5.5

3.6

6.0

DOUBLE WALL

HEAT EXCHANGER

SINGLE WALL

HEAT EXCHANGER

MODEL

RXLD-28

RXLD-52

RXLS-28

RXLS-52

BTUH

28,000 2.8 1.0

52,000

28,000

52,000

GPM

5.2

2.8

5.2

PD (FT.)

0.9

0.7

1.3

RADIANT FLOOR APPLICATION - HEAT EXCHANGER SELECTION TABLE

0

150

F SOURCE (TANK)

4.9

8.3

5.0

8.4

DOUBLE WALL

HEAT EXCHANGER

SINGLE WALL

HEAT EXCHANGER

MODEL

RXLD-28

RXLD-52

RXLS-28

RXLS-52

1400F SOURCE (TANK)

BTUH GPM PD (FT.)

28,000

52,000

28,000

52,000

2.8

5.2

2.8

5.2

1.0

0.9

0.7

1.3

BTUH GPM

48,000

82,000

50,000

84,000

HEAT EXCHANGER PRESSURE DROP

For Secondary Loop Flow Calculations

PD (FT.)

1.1

1.1

1.7

PD (FT.)

3.0

2.4

2.3

3.6

BTUH

55,000

79,000

68,000

95,000

BTUH GPM

65,000

110,000

98,000

115,000

GPM

0

F SOURCE (TANK)

160

11.1

11.6

PROMAX SL WATER HEATER

CROSS-REFERENCE

PROMAX SL

WATER HEATER

STANDARD

VENT

DIRECT

VENT

POWER

VENT

POWER

DIRECT

VENT

MODELS

GCVH-40L
GCVT-50L
GCVX-50L
GCV-65L

FCG-75L

GDV-40L

GDVT-50L

GDV-75L
GPVT-40L

GPVT-50L
GPVX-50L
GPS-75L

GPD-40L

GPDX-50L
GPD-75L

OUTPUT

29,600
38,000
50,050
49,400
57,000

30,780
40,500
44,550

39,000
39,500
49,400
64,000
30,400
47,450
53,200

5.5

2.3

6.8

9.6

6.5

9.8

PD (FT.)

3.7

0.5

4.3

8.5

PD (FT.)

5.3

4.1

8.9

6.2

For Technical Information and Automated Fax Service, call 800-527-1953. A.O. Smith Corporation reserves the right to make product changes or improvements without prior notice.

June 2010R

www.hotwater.com

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AOSRG46600