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Switching Relays

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More About Switching Relays

Switching relays are used to control the flow of water in a heating system by monitoring temperatures and adjusting boiler water temperature to match the demand. They are used in coordination with circulator pumps and programmable thermostats to control zoning in a hydronic heating system. This makes them ideal for indirect water heaters and priority zoning applications. They maximize efficiency and reduce fuel usage, which saves money. In addition, they provide intermediate switching of a line voltage device from a low voltage controller. Switching relays are available in one to six zone models, and if additional zones are required expandable models provide the ability to expand up to 20 zones.

We offer a wide selection of Taco, Honeywell , Argo, and Bell & Gossett switching relays for residential and light commercial applications.
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Product Image of 1 Zone Switching Relay
1 Zone Switching Relay
SKU: SR501-4
Taco
SKU: SR501-4
Brand: Taco
(159)
$71.42 each
In Stock
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Product Image of 2 Zone Switching Relay w/ Priority
2 Zone Switching Relay w/ Priority
SKU: SR502-4
Taco
SKU: SR502-4
Brand: Taco
(32)
$175.36 each
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Product Image of 2 Zone 120V Switching Relay w/ DPST Switching, RA832A1066
$112.00 each
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Product Image of 3 Zone Switching Relay
3 Zone Switching Relay
SKU: SR503-4
Taco
SKU: SR503-4
Brand: Taco
(50)
$185.24 each
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Product Image of 4 Zone Switching Relay w/ Priority
4 Zone Switching Relay w/ Priority
SKU: SR504-EXP-4
Taco
SKU: SR504-EXP-4
Brand: Taco
(41)
$237.95 each
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Product Image of 1 Zone 120V Switching Relay w/ Internal Transformer, 1 SPST Line Relay, RA89A1074
$92.44 each
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Product Image of Switching Relay w/ Internal Transformer DPST Line Voltage Relays, R845A1030
$110.44 each
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Product Image of Replacement Fuse - 6 Amp (10 Pack)
Replacement Fuse - 6 Amp (10 Pack)
SKU: SR6A-001RP
Taco
SKU: SR6A-001RP
Brand: Taco
(13)
$25.27 each
In Stock
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Product Image of 2 Zone Pump Controller Switching Relay with Priority Protection
$103.95 each
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Product Image of Replacement Fuse - 5 Amp (10 Pack)
Replacement Fuse - 5 Amp (10 Pack)
SKU: SR5A-005RP
Taco
SKU: SR5A-005RP
Brand: Taco
(5)
$16.74 each
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Product Image of 1 Zone Pump Controller Switching Relay with Surge & Fuse Protection (DPDT)
$53.75 each
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Product Image of 3 Zone Pump Controller Switching Relay with Priority Protection
$125.95 each
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Product Image of Universal Switching Relay w/ Internal Transformer, R8845U1003
$87.72 each
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Product Image of ARM-6P 6 Zone Expandable Switching Relay
ARM-6P 6 Zone Expandable Switching Relay
SKU: ARM6P
Argo
SKU: ARM6P
Brand: Argo
(51)
$399.25 each
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Product Image of ARM-3P 3 Zone Expandable Switching Relay
ARM-3P 3 Zone Expandable Switching Relay
SKU: ARM3P
Argo
SKU: ARM3P
Brand: Argo
(51)
$247.33 each
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Product Image of 24 Volt Replacement Relay
24 Volt Replacement Relay
SKU: SR024-001RP
Taco
SKU: SR024-001RP
Brand: Taco
(11)
$42.75 each
In Stock
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Product Image of 1 Zone Switching Relay
1 Zone Switching Relay
SKU: AR822II
Argo
SKU: AR822II
Brand: Argo
(8)
$93.79 each
In Stock
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Product Image of ARM-4P 4 Zone Expandable Switching Relay
ARM-4P 4 Zone Expandable Switching Relay
SKU: ARM4P
Argo
SKU: ARM4P
Brand: Argo
(51)
$377.47 each
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Product Image of 6 Zone Pump Controller Switching Relay with Priority Protection
$198.95 each
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Product Image of 4 Zone Pump Controller Switching Relay with Priority Protection
$179.95 each
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Product Image of Isolation Relay for Up to 3 Zones
Isolation Relay for Up to 3 Zones
SKU: IR882
Argo
SKU: IR882
Brand: Argo
(19)
$115.86 each
In Stock
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Product Image of 304P Switching Relay - 4 Zones w/ Priority
$213.15 each
In Stock
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Product Image of 301P Switching Relay - 1 Zone
301P Switching Relay - 1 Zone
SKU: 301P
Tekmar
SKU: 301P
Brand: Tekmar
(2)
$92.77 each
In Stock
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Product Image of 306P Switching Relay - 6 Zones w/ Priority
$275.07 each
In Stock
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Product Image of 3 Zone Expandable Switching Relay w/ Priority
$224.00 each
In Stock
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Product Image of Replacement Fuse - 1 Amp (10 Pack)
Replacement Fuse - 1 Amp (10 Pack)
SKU: SR1A-001RP
Taco
SKU: SR1A-001RP
Brand: Taco
$25.27 each
In Stock
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Product Image of 1 Zone Expandable Switching Relay w/ Priority
$93.00 each
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Product Image of 1 Zone Switching Relay
1 Zone Switching Relay
SKU: SR501-EXP-4
Taco
SKU: SR501-EXP-4
Brand: Taco
(41)
$173.56 each
In Stock
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Product Image of 120 Volt Replacement Relay
120 Volt Replacement Relay
SKU: SR120-001RP
Taco
SKU: SR120-001RP
Brand: Taco
(4)
$40.65 each
In Stock
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Product Image of 302P Switching Relay - 2 Zones w/ Priority
$164.18 each
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Product Image of 120V, 60 Hz Switching Relay with SPDT switching, RA889A1001
$81.72 each
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Product Image of Hydronic Three Zone Switching Relay
$180.69 each
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Product Image of ARM-2P 2 Zone Expandable Switching Relay
ARM-2P 2 Zone Expandable Switching Relay
SKU: ARM2P
Argo
SKU: ARM2P
Brand: Argo
(51)
$216.12 each
In Stock
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Product Image of 4 Zone Expandable Switching Relay w/ Priority
$216.68 each
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Product Image of Hydronic Four Zone Switching Relay
$224.74 each
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Product Image of 5 Zone Pump Controller Switching Relay with Priority Protection
$179.58 each
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Product Image of 303P Switching Relay - 3 Zones w/ Priority
$177.16 each
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Product Image of 6 Zone Expandable Switching Relay w/ Priority
$262.00 each
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Product Image of Taco PC705 Variable Speed Pump Control
Taco PC705 Variable Speed Pump Control
SKU: PC705-2
Taco
SKU: PC705-2
Brand: Taco
(2)
$494.06 each
In Stock
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Product Image of Fuses for SP-82, SP-83 (Pack of 5)
$9.16 each
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Product Image of 120V, 50/60 Hz Heavy Duty Switching Relay w/ Integral Transform, DPST or SPST Line Voltage Relays, R847A1085
$143.10 each
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Product Image of Hydronic Six Zone Switching Relay
$314.64 each
In Stock
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Product Image of Taco Boiler Reset Control
Taco Boiler Reset Control
SKU: PC700-2
Taco
SKU: PC700-2
Brand: Taco
(5)
$371.78 each
In Stock
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Product Image of Hydronic Single Zone Switching Relay
$66.96 each
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Product Image of 3 Zone Switching Relay with priority
3 Zone Switching Relay with priority
SKU: AR861-3II
Argo
SKU: AR861-3II
Brand: Argo
(1)
$267.02 each
In Stock
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Product Image of Taco Boiler Reset Control 2-Stage
Taco Boiler Reset Control 2-Stage
SKU: PC702-1
Taco
SKU: PC702-1
Brand: Taco
(2)
$456.89 each
In Stock
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Product Image of DPST Line Voltage Relay, RA832A1074
DPST Line Voltage Relay, RA832A1074
SKU: RA832A1074
Resideo
SKU: RA832A1074
Brand: Resideo
$175.62 each
In Stock
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Product Image of Add-On Zoning Module For ARM Control, 1 Zone
Add-On Zoning Module For ARM Control, 1 Zone
SKU: AD1
Argo
SKU: AD1
Brand: Argo
(4)
$113.20 each
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More About Switching Relays
Switching relays are used to control the flow of water in a heating system by monitoring temperatures and adjusting boiler water temperature to match the demand. They are used in coordination with circulator pumps and programmable thermostats to control zoning in a hydronic heating system. This makes them ideal for indirect water heaters and priority zoning applications. They maximize efficiency and reduce fuel usage, which saves money. In addition, they provide intermediate switching of a line voltage device from a low voltage controller. Switching relays are available in one to six zone models, and if additional zones are required expandable models provide the ability to expand up to 20 zones.

We offer a wide selection of Taco, Honeywell , Argo, and Bell & Gossett switching relays for residential and light commercial applications.
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Show In Stock Only (56)

Application

Zoning (38)
Boiler Reset (3)
Replacement Part (6)

Review Score

(32)
(5)
(1)

Price Range

$1 to $5 (1)
$5 to $10 (1)
$10 to $15 (1)
$15 to $20 (3)
$25 to $30 (2)
$40 to $45 (2)
$50 to $60 (1)
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