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SR506-EXP-4 has been discontinued
Discontinued January 3, 2025
This product was discontinued by the manufacturer.
MANUALS (3)
This item replaces: SR506-EXP-1
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Direct Replacement:
6 Zone Next Generation Switching Relay, Expandable
Product Highlights
–
120 VAC Input
6
20 Amps
120v
Description
–
Taco Switching Relays combine clearly labeled PC board layouts with advanced features that allow
for total system customization. Whether using basic priority switching or the advanced features
of the -EXP controls, the job is made easy. External indicator lights provide instant diagnostic
feedback, making a snap of service calls or new installation start-ups. All switching relays are UL
and CSA listed, use standard "ice cube" replaceable relays and are compatible with conventional
and programmable thermostats.
Whether you want to expand up to 20 zones or utilize the advanced features of the PowerPort Cards and Add-on Power Controls, Taco -EXP controls allow for simple integration of advanced features. Plug in any combination of cards and controls to optimize the operation of any system.
Features include:
Additional -EXP Features
Whether you want to expand up to 20 zones or utilize the advanced features of the PowerPort Cards and Add-on Power Controls, Taco -EXP controls allow for simple integration of advanced features. Plug in any combination of cards and controls to optimize the operation of any system.
Features include:
- External Indicator Lights
- Switchable Priority
- Simplified Wiring
- Fully Enclosed Snap-Out Relays
- Compact Design
- Fuse Protected
- 100% Factory Tested
- Isolated End Switch
- Contractor Friendly PC Board Layout
- Universal Thermostat Compatibility
- UL and CSA Approved
- 24 Volt Power Input or Output Terminal
- Extended 3 Year Warranty
- Made in the USA
Additional -EXP Features
- Plug-in PowerPort Card Slots
- Add-on Power Control Plug
- Expandable to 20 Zones
- Interface with -EXP Zone Valve Controls
Specs
–
| Application: | Zoning |
|---|---|
| Number of Zones: | 6 |
| Amperage: | 20 |
| Power Control Plugs: | 1 |
| Power Method: | 120 VAC Input |
| Voltage: | 120v |
Questions?
Speak with a real person who will go out of the way to help!
Call or text 888-757-4774
Monday – Thursday
8am–7:45pm
Friday
9am–7:45pm
Saturday – Sunday
9am–5:45pm
Compare Similar Products
Brand
Number of Zones
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3 Replacement Parts
Replacement Fuse - 5 Amp (10 Pack)
SKU: SR5A-005RP
TacoReplacement Fuse - 1 Amp (10 Pack)
SKU: SR1A-001RP
TacoReplacement Fuse - 6 Amp (10 Pack)
SKU: SR6A-001RP
Taco
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Product Reviews
4.6 out of 20 reviews
89% would recommend this product
5 star
80%
4 star
10%
3 star
0%
2 star
10%
1 star
0%
Customer Images
Most Liked Positive Review
Did what I neede it to do.
This relay worked great with the hot water boiler that was installed.
VS
Most Liked Negative Review
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Taco Zone controller has problem
The transformer is undersized to fit in the box. Mine went out so I bought another transformer --I guess industrial grade one and put it in...working well for the past 3 weeks.
Showing 1-10 of 20 reviews
Defective part
I was without heat and hot water. Shipping was excellent and timely. However day I received switching relay i I changed out defective unit and replaced with new. Circuit board was bad. Tried contacting Supply House for new unit to get shipped immediately as I had no heat or hot water….. no deal….. had to go thru return order new process again. I declined. I returned and got a new unit elsewhere.
Bubba
Boonville NY
3 years ago
Verified Buyer
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Great Service
Was able to work with SupplyHouse to get the product I needed to fix my furnace.
TAK
Somerset, PA
3 years ago
Verified Buyer
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Worth the upgrade
All of the nest thermostats needed rewired, to work with the newer controller requires 18/3 wire from the nest thermostats not the 18/2.
Russell
Dedham, MA
4 years ago
Verified Buyer
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This product is doing exactly what we hoped venting without
I found it comical that they apologized for a black cover instead of green😁
THOMAS
ME
4 years ago
Verified Buyer
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Yes, simple to install.
simple connection, easy and better operations compare to the I Link (Azel) , Which I replaced,
work with any brand thermostat. only fault its larger than the I Link
Rob
Montclair,NJ
5 years ago
Verified Buyer
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Isolated incident
I received an SR506 that when powered burned up the power supply capacitor. Being an electronics designer and engineer I noticed it had been installed backwards. I replaced the Cap and its all good. Would have returned the unit for replacement but can't leave people without heat. Never had any other issues.
603OBS
New Hampshire
5 years ago
Verified Buyer
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Does what it says on the tin
This Taco zone controller was fairly simple to hook up. The instructions could be better, but I know from a previous experience that the Taco tech support is good if you need it.
Mike
New Bedford
5 years ago
Verified Buyer
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Best controller
I created a 12 zones heating system using two expendable Taco units, very easy to install and setup.
Marcin
Delmar NY
6 years ago
Verified Buyer
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yes
It has the extra terminal for common power for thermostats
Michael
New York
7 years ago
Verified Buyer
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Great product
I used this to replace my controller that was fried during a storm. If you have the skills and knowledge to order the correct part, you shouldn't have any problem hooking it up.
Hubbs
Tully, NY
7 years ago
Verified Buyer
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Product Q&A
2 Questions2 Questions
Q: what is the difference between priority && non priority why would I need one over the other. I have a 6 zone hot water heating system which I intend to include a Amtrol BoilerMate
Asked by snapsplash 10 years ago
Add your answer
Verified Reply- SupplyHouse StaffPriority gives "priority" to the domestic heating zone. This is ideal because if you were taking a shower, the system would make sure there was hot water in the shower before satisfying the space heating.
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Q: Can I purchase a replacement transformer for a Taco sr506-ext-4 switching relay
Asked by Clarky 11 years ago
Add your answer
Verified Reply- SupplyHouse StaffThis part is not available as a replacement part.
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