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Relays

55 products

Showing 1 - 55 of 55 products

Switching relays, electric heat relays and damper relays for HVAC and hydronic controls.

Switching relays (RA89, RA832, RA889, R8222, R8228) let a 24 V thermostat or control switch a line-voltage load such as a circulator, fan or burner. Choose by coil voltage and by contact arrangement: SPST, SPDT or DPST.

Electric heat relays (RC840, R841, RT850) switch baseboard and duct heaters. Models with a built-in transformer (T suffix) supply their own 24 V, and the RT850 is solid state for silent, high-cycle switching. Heat sequencers (R24AA) stage electric elements on one at a time.

Related: contactors, transformers, zone dampers.

Popular in this collection: Honeywell Home RC840/U Electric Heat Relay.

Frequently asked questions

What is a switching relay used for?

It lets a 24V thermostat or control switch a line voltage load such as a circulator pump, fan or burner.

Which relay do I need for a baseboard or duct heater?

Use an electric heat relay such as the RC840 or R841. Models with a T suffix include a built-in transformer, so they supply their own 24V control power.

How do I match a replacement relay?

Match the coil voltage and the contact arrangement (SPST, SPDT or DPST) and check the contact rating against the load you are switching.

Showing 1 - 55 of 55 products

Resideo Electromechanical Relay Without Transformer

Resideo Electromechanical Relay Without Transformer

Honeywell Home Honeywell Home RC840/U Electromechanical Relay Without Transformer

$68.51

In stock, 8 units

Honeywell Home SDCR/U Slave Damper Control Relay

Honeywell Home Honeywell Home SDCR/U Slave Damper Control Relay

$403.11

Special order · ships in 3–4 weeks

Resideo RT850T-240/U Solid State Electric Heat Relay with Built-In Transformer, 208–240/24 V

Resideo Resideo RT850T-240/U Solid State Electric Heat Relay with Built-In Transformer, 208–240/24 V

$126.44

Special order · ships in 3–4 weeks

Honeywell Home RC840T-347/U Electromechanical Electric Heat Relay with Built-In Transformer, 347/24 V

Honeywell Home Honeywell Home RC840T-347/U Electromechanical Electric Heat Relay with Built-In Transformer, 347/24 V

$118.36

Special order · ships in 3–4 weeks

Resideo RT850/U Solid State Electric Heat Relay without Transformer, 120/208/240/347 V

Resideo Resideo RT850/U Solid State Electric Heat Relay without Transformer, 120/208/240/347 V

$95.69

Special order · ships in 3–4 weeks

Honeywell Home RC840T-277/U Electromechanical Electric Heat Relay with Built-In Transformer, 277/24 V

Honeywell Home Honeywell Home RC840T-277/U Electromechanical Electric Heat Relay with Built-In Transformer, 277/24 V

$105.57

Special order · ships in 3–4 weeks

Resideo RA889A1001/U Switching Relay, 120 VAC 60 Hz, SPDT Two Line Voltage Loads, SPST Low Voltage

Resideo Resideo RA889A1001/U Switching Relay, 120 VAC 60 Hz, SPDT Two Line Voltage Loads, SPST Low Voltage

$96.19

Special order · ships in 3–4 weeks

Resideo R841C1169/U Electric Heat Relay with Built-In Transformer, 208–240/24 V

Resideo Resideo R841C1169/U Electric Heat Relay with Built-In Transformer, 208–240/24 V

$123.06

Special order · ships in 3–4 weeks

Resideo R841C1151/U Electric Heat Relay with Built-In Transformer, 600/24 V

Resideo Resideo R841C1151/U Electric Heat Relay with Built-In Transformer, 600/24 V

$138.04

Special order · ships in 3–4 weeks

Resideo RA832A1082/U Switching Relay, 120 VAC 50/60 Hz, DPST Line Voltage, SPST Low Voltage

Resideo Resideo RA832A1082/U Switching Relay, 120 VAC 50/60 Hz, DPST Line Voltage, SPST Low Voltage

$249.96

Special order · ships in 3–4 weeks

Resideo RA89A1116/U Switching Relay, 120 VAC 50/60 Hz, SPST Line Voltage

Resideo Resideo RA89A1116/U Switching Relay, 120 VAC 50/60 Hz, SPST Line Voltage

$180.36

Special order · ships in 3–4 weeks

Resideo R841C1029/U Electric Heat Relay with Built-In Transformer, 240/24 V

Resideo Resideo R841C1029/U Electric Heat Relay with Built-In Transformer, 240/24 V

$109.19

Special order · ships in 3–4 weeks

Resideo RA832A1074/U Switching Relay, 240 VAC 50/60 Hz, DPST Line Voltage and Low Voltage Load

Resideo Resideo RA832A1074/U Switching Relay, 240 VAC 50/60 Hz, DPST Line Voltage and Low Voltage Load

$206.73

Special order · ships in 3–4 weeks

Resideo R8239D1007/U Fan Center, 120 V, 40 VA Transformer and DPST Relay

Resideo Resideo R8239D1007/U Fan Center, 120 V, 40 VA Transformer and DPST Relay

$123.50

Special order · ships in 3–4 weeks

Resideo R841C1144/U Electric Heat Relay with Built-In Transformer, 347/24 V

Resideo Resideo R841C1144/U Electric Heat Relay with Built-In Transformer, 347/24 V

$126.71

Special order · ships in 3–4 weeks

Resideo R8239B1043/U Fan Center, DPDT Relay with 2 Normally Open and 2 Normally Closed Contacts

Resideo R8239B1043/U Fan Center, DPDT Relay with 2 Normally Open and 2 Normally Closed Contacts

Resideo Resideo R8239B1043/U Fan Center, DPDT Relay with 2 Normally Open and 2 Normally Closed Contacts

$89.20

Special order · ships in 3–4 weeks

Resideo R8285D5001/U Fan Center, DPST, 120 V, 50 VA Transformer, for SV9500/SV9600

Resideo Resideo R8285D5001/U Fan Center, DPST, 120 V, 50 VA Transformer, for SV9500/SV9600

$70.01

Special order · ships in 3–4 weeks

Resideo R8285B1038/U Fan Center, 120 V, 40 VA Transformer and DPDT Relay

Resideo Resideo R8285B1038/U Fan Center, 120 V, 40 VA Transformer and DPDT Relay

$85.24

Special order · ships in 3–4 weeks

Resideo R847A1085/U Line Voltage Relay, 120 VAC 60 Hz, DPST or SPST

Resideo Resideo R847A1085/U Line Voltage Relay, 120 VAC 60 Hz, DPST or SPST

$168.46

Special order · ships in 3–4 weeks

Resideo R8229A1005/U DPST Relay, Up to Two Electric Heat Elements Plus Fan Motor, 277 VAC

Resideo Resideo R8229A1005/U DPST Relay, Up to Two Electric Heat Elements Plus Fan Motor, 277 VAC

$101.46

Special order · ships in 3–4 weeks

Resideo R8239A1003/U Fan Center, 120 V Primary, Metal Cover

Resideo R8239A1003/U Fan Center, 120 V Primary, Metal Cover

Resideo Resideo R8239A1003/U Fan Center, 120 V Primary, Metal Cover

$143.71

Special order · ships in 3–4 weeks

Resideo R8229A1021/U Electric Heat Relay, DPST, with Adapter Plate and Mounting Hardware

Resideo Resideo R8229A1021/U Electric Heat Relay, DPST, with Adapter Plate and Mounting Hardware

$132.89

Special order · ships in 3–4 weeks

Resideo R8285B1053/U Fan Center, 40 VA Transformer and R8222D Plug-In Relay, 120/208/240 V

Resideo Resideo R8285B1053/U Fan Center, 40 VA Transformer and R8222D Plug-In Relay, 120/208/240 V

$91.13

Special order · ships in 3–4 weeks

Resideo R8225D1003/U Fully Enclosed Relay, DPST Normally Open, 24 V Coil, Leadwire Connections

Resideo Resideo R8225D1003/U Fully Enclosed Relay, DPST Normally Open, 24 V Coil, Leadwire Connections

$117.96

Special order · ships in 3–4 weeks

Resideo R8222U1079/U Relay, DPST Normally Open, 24 V Coil, Quick Connect Terminals

Resideo R8222U1079/U Relay, DPST Normally Open, 24 V Coil, Quick Connect Terminals

Resideo Resideo R8222U1079/U Relay, DPST Normally Open, 24 V Coil, Quick Connect Terminals

$31.87

Special order · ships in 3–4 weeks

Resideo R8225A1017/U Fully Enclosed Relay, SPDT, 24 V Coil, Leadwire Connections

Resideo Resideo R8225A1017/U Fully Enclosed Relay, SPDT, 24 V Coil, Leadwire Connections

$101.03

Special order · ships in 3–4 weeks

Resideo R8222V1003/U Relay, DPDT, 24 V Coil, Quick Connect Terminals

Resideo R8222V1003/U Relay, DPDT, 24 V Coil, Quick Connect Terminals

Resideo Resideo R8222V1003/U Relay, DPDT, 24 V Coil, Quick Connect Terminals

$32.49

Special order · ships in 3–4 weeks

Resideo R8239B1076/U Fan Center, Transformer and R8222D Relay on 4 x 4 Plate, 120/208/240 V

Resideo Resideo R8239B1076/U Fan Center, Transformer and R8222D Relay on 4 x 4 Plate, 120/208/240 V

$107.64

Special order · ships in 3–4 weeks

Resideo R24ED5007/U Heat Sequencer, 5 Switches, On 1–160 sec, Off 1–160 sec

Resideo Resideo R24ED5007/U Heat Sequencer, 5 Switches, On 1–160 sec, Off 1–160 sec

$69.99

Special order · ships in 3–4 weeks

Resideo R24BA1006/U Heat Sequencer, 2 Switches, On 1–20 sec, Off 40–110 sec

Resideo Resideo R24BA1006/U Heat Sequencer, 2 Switches, On 1–20 sec, Off 40–110 sec

$32.37

Special order · ships in 3–4 weeks

Resideo R24DB4005/U Heat Sequencer, 4 Switches, On 1–110 sec, Off 1–110 sec

Resideo Resideo R24DB4005/U Heat Sequencer, 4 Switches, On 1–110 sec, Off 1–110 sec

$56.71

Special order · ships in 3–4 weeks

Resideo R24AA3004/U Heat Sequencer, 1 Switch, On 30–90 sec, Off 1–30 sec

Resideo Resideo R24AA3004/U Heat Sequencer, 1 Switch, On 30–90 sec, Off 1–30 sec

$25.26

Special order · ships in 3–4 weeks

Resideo R4222N1002/U Pilot Duty Relay, DPDT, 120 V Coil, Quick Connect Terminals

Resideo Resideo R4222N1002/U Pilot Duty Relay, DPDT, 120 V Coil, Quick Connect Terminals

$46.90

Special order · ships in 3–4 weeks

Resideo R24AA1008/U Heat Sequencer, 1 Switch, On 1–20 sec, Off 40–110 sec

Resideo Resideo R24AA1008/U Heat Sequencer, 1 Switch, On 1–20 sec, Off 40–110 sec

$25.26

Special order · ships in 3–4 weeks

Resideo R4222B1082/U Relay, SPDT, 120 V Coil, Quick Connect Terminals

Resideo Resideo R4222B1082/U Relay, SPDT, 120 V Coil, Quick Connect Terminals

$29.90

Special order · ships in 3–4 weeks

Resideo R24CB4007/U Heat Sequencer, 3 Switches, On 1–110 sec, Off 1–110 sec

Resideo Resideo R24CB4007/U Heat Sequencer, 3 Switches, On 1–110 sec, Off 1–110 sec

$49.29

Special order · ships in 3–4 weeks

Resideo R24BA3002/U Heat Sequencer, 2 Switches, On 30–90 sec, Off 1–30 sec

Resideo Resideo R24BA3002/U Heat Sequencer, 2 Switches, On 30–90 sec, Off 1–30 sec

$32.37

Special order · ships in 3–4 weeks

Resideo R24AA2006/U Heat Sequencer, 1 Switch

Resideo Resideo R24AA2006/U Heat Sequencer, 1 Switch

$29.91

Special order · ships in 3–4 weeks

Discontinued

Resideo Q633A1007/U Plate-Mounted Relay Receptacle, 8 Leadwires

Resideo Resideo Q633A1007/U Plate-Mounted Relay Receptacle, 8 Leadwires

$53.43

Sold out

Discontinued

Resideo 129384A/U Case/Cover for R8222/R8228 Relays

Resideo Resideo 129384A/U Case/Cover for R8222/R8228 Relays

$103.76

Sold out

Electromechanical Heating Relay with 208/240V Transformer

Honeywell Home Honeywell Home RC840T-240/U Electromechanical Heating Relay with 208/240V Transformer

$102.76

In stock, 1 unit

Resideo 12 VA General Purpose Relay with DPDT Switching

Resideo 12 VA General Purpose Relay with DPDT Switching

Resideo Resideo R8222D1014/U 12 VA General Purpose Relay with DPDT Switching

$28.79

In stock, 219 units

Electromechanical Relay with 24 V to 120 V Transformer

Honeywell Home Honeywell Home RC840T-120/U Electromechanical Relay with 24 V to 120 V Transformer

$82.13

In stock, 9 units

Internal Transformer Switching Relay with Low Voltage Contacts

Resideo Resideo RA832A1066/U Internal Transformer Switching Relay with Low Voltage Contacts

$131.84

In stock, 19 units

Multisystem Switching Relay with Internal Transformer

Resideo Resideo R8845U1003/U Multisystem Switching Relay with Internal Transformer

$103.26

In stock, 12 units

Switching Relay with Internal Transformer

Resideo Resideo R845A1030/U Switching Relay with Internal Transformer

$130.00

In stock, 3 units

Resideo R841D1036/U 24 V SPST switching Electric Heater Relay

Resideo Resideo R841D1036/U 24 V SPST Switching Electric Heater Relay

$85.94

In stock, 12 units

24 V SPST switching Electric Heater Relay

Resideo Resideo R841C1227/U 24 V SPST Switching Electric Heater Relay

$125.29

In stock, 10 units

General Purpose Relay with DPDT Switching

Resideo General Purpose Relay with DPDT Switching

Resideo Resideo R8222N1011/U General Purpose Relay with DPDT Switching

$30.44

In stock, 11 units

Resideo General Purpose Relay with SPDT Switching

Resideo General Purpose Relay with SPDT Switching

Resideo Resideo R8222B1067/U General Purpose Relay with SPDT Switching

$26.89

In stock, 73 units

Resideo 208/240 Vac General Purpose Relay with DPDT switching

Resideo 208/240 Vac General Purpose Relay with DPDT switching

Resideo Resideo R4222D1021/U 208/240 Vac General Purpose Relay with DPDT Switching

$32.39

In stock, 7 units

Resideo 120 V General Purpose Relay with DPDT switching

Resideo 120 V General Purpose Relay with DPDT switching

Resideo Resideo R4222D1013/U 120 V General Purpose Relay with DPDT Switching

$30.99

In stock, 24 units

Pilot Relay, 10 Amp SPDT, 10-30 Vac/dc/120 Vac Coil, NEMA 1 Housing

Functional Devices Functional Devices RIBU1C Pilot Relay, 10 Amp SPDT, 10-30 Vac/dc/120 Vac Coil, NEMA 1 Housing

$56.25

In stock, 9 units

DiversiTech Sequencer, 2 Main Circuits, DPST-NO, Delay On 1-24 sec, Delay Off 45-75 sec

DiversiTech Sequencer, 2 Main Circuits, DPST-NO, Delay On 1-24 sec, Delay Off 45-75 sec

DiversiTech DiversiTech HDR-201 Sequencer, 2 Main Circuits, DPST-NO, Delay On 1-24 sec, Delay Off 45-75 sec

$32.56

Only 3 units left

Sequencer, 1 Main Circuit, SPST-NO, Delay On 1-24 sec, Delay Off 45-75 sec

DiversiTech Sequencer, 1 Main Circuit, SPST-NO, Delay On 1-24 sec, Delay Off 45-75 sec

DiversiTech DiversiTech HDR-101 Sequencer, 1 Main Circuit, SPST-NO, Delay On 1-24 sec, Delay Off 45-75 sec

$26.80

Only 3 units left

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