©Johnstone Supply eCatalog 216

HYDRONICS Boiler Controls

Low Water Cut-Off For Water Boilers • For hot water boilers of any size, including steam • Protects against low water conditions with circuit for low water alarm • Manual reset • Designed with 1" NPT equalizing pipes • Maximum boiler pressure: 50 PSI

• 120VAC — maximum F/L amps 10.2; maximum L/R amps 61.2; 240VAC — maximum F/L amps 5.1; maximum L/R amps 30.6 • Pilot duty: 120/240VAC, 60 Hz, 125VA; 115VDC, 0.5A WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

Order #

Mfg. #

Model #

L86-135

143100

63-M

No. 2 Switches • For series 47, 247, 51, 51S, 53, 63 and 847 water feeders to add low water cut-off function • Provides flexibility for selection of functions desired

• L38-775 has manual reset WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

Order #

Mfg. #

Model #

Description

Volts

L38-774 L38-775

110000 110100

2

Low Water Cut-Off Switch 120/240 Low Water Cut-Off Switch 120/240

2M

Low Water Cut-Off For Hot Water Boilers Electric • For residential and, where codes allow, commercial applications • Electro-mechanical operation • Automatic reset • No blow-down required Specifications:

• Maximum water pressure: 160 PSI • Voltage across probe to ground: 125VAC • Power consumption: 15VA • Probe sensitivity: 6,000 ohms WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

• Maximum ambient temperature: 120°F • Maximum water temperature: 250°F

Fig. Order #

Mfg. #

Model # RB-122

Volts

For Use With

A

B

L38-788

A

144676

120VAC

—

Replacement Probe B L41-531 354083

PA-RB-122

—

RB-122

Low Water Cut-Off for Hot Water Boilers Electric • For residential applications • Automatic reset resumes operation after a power outage

• LED for power to the unit and presence of water in the boiler WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

Order #

Mfg. #

Model # RB-24E

Volts

L38-787

144692

24

Universal Wire Harness Kits For Atmospheric and Sealed Combustion Boilers • Used with all RB-24s (sold separately)

• Both harness kits consist of three Molex wiring harnesses; a common “connector cable” and two “Y” harnesses WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

• L41-528 used in most 24-volt “atmospheric” hot water boiler applications that use 6-pin aquastats or vent damper • L41-529 used in 24-volt “sealed combustion” hot water boiler applications

Fig. Order #

Mfg. # Model #

Volts

Fig. Order #

Mfg. # Model #

Volts

A

B

L41-528

L41-529

A

144681 UWH-RB-24-A 24

B

144682 UWH-RB-24-S 24

540

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