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Universal Switching Relay w/ Internal Transformer, R8845U1003
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$99.29 each
In Stock
Get 19 Tomorrow, Jun 25
Order by 6PM, receive Tomorrow
MANUALS (2)
This item replaces: R182C1051
Free Shipping This item ships free
Easy Returns No restocking fee for 90 days
Product Highlights
–
120V
Two SPST, plus PowerPile® rated low voltage SPST relay
1
6-1/4"
7.4 Amps
120v
Description
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Honeywell R8845U1003 is a universal switching relay with internal transformer. This switching relay provides intermediate switching of line voltage and low voltage devices from a line voltage or low voltage controller. It is typically applied in Hydronic heating systems.
Honeywell Universal Switching Relays R8845U with 24 V transformer provide intermediate switching of line-and low-voltage devices from a line- or low-voltage controller and is typically applied in Hydronic heating systems.
Features:
Honeywell Universal Switching Relays R8845U with 24 V transformer provide intermediate switching of line-and low-voltage devices from a line- or low-voltage controller and is typically applied in Hydronic heating systems.
Features:
- Two troubleshooting LED
- Push-to-test button
- Replaceable transformer fuse
- Low-voltage contact rating for Powerpile applications
- Long-life DC relay drive control technology
- Relay for use with external 24 Vac or 24 Vdc supply, with line-voltage control, or with internal 24 V transformer supply
- One model replaces many competitor models
- One model may replace many Honeywell models:R182A,B,C,J; R482A,B,C,J; R845; R882A,B,C,J and RA832
- Includes integral transformer, enclosure
- Approvals of Canadian Underwriters Laboratories and Underwriters Laboratories Inc.
Specs
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| Application: | Zoning |
|---|---|
| Number of Zones: | 1 |
| Width: | 4-7/16" |
| Height: | 6-1/4" |
| Amperage: | 7.4 |
| Power Method: | 120V |
| Voltage: | 120v |
| Hertz: | 60 |
| Depth (Inches): | 3-1/2" |
| Ambient Conditions: | -20 F to +120 F 0-90% RH non-condensing |
| Switch Action: | Two SPST, plus PowerPile® rated low voltage SPST relay |
| Relays: | Low Voltage SPST |
| Thermostat Compatibility: | Electronic 2-wire Electronic 3-wire Honeywell Electromechanical |
Questions?
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Product Reviews
4.88 out of 25 reviews
100% would recommend this product
5 star
88%
4 star
12%
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Showing 1-10 of 25 reviews
Worked as expected
Switched my old millivolt heating system to use modern Google Nest thermostat. Family loves it!
skywalk7
Palo Alto, CA
3 years ago
Verified Buyer
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Good Product - big improvement over its predecessor.
The first one I ordered arrived defective. Was not assembled at the factory correctly. The replacement that came very quickly, did work and is a big improvement over its predecessor and at a lower cost. Has a test button and functional LED indicators on the PCB.
MPL
NJ
3 years ago
Verified Buyer
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Perfect solution for using Nest Thermostats with Taco SR 506
I installed three Universal Switching relays to connect three Nest thermostats to my TACO SR 506 relay that controls my forced hot water heating system. The installation required new (3 conductor) wires be run from the new relays to the thermostats to replace the 2 conductor wire that previously worked with the low voltage thermostats. The new relays provide the 14v AC required by Nest and the low voltage signal required by the Taco system. The Nest thermostat trips the universal relay which in turn trips the low voltage relay in the SR 506.
Jeff the Homeowner
New Hampshire
4 years ago
Verified Buyer
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Super supplier
Great products and service. Their tech staff are knowledgeable and helpful if you have a problem.
Alwsys my first choice.
Hugh
Minnesota
5 years ago
Verified Buyer
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Worked perfectly
It worked without hesitation. Great choice.
Daniel
Bronx
5 years ago
Verified Buyer
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Works perfectly
Used for controlling a gas wall heater's millivolt valve with a wifi thermostat (Ecobee).
Supplyhouse's response time was phenomenal. It was at the door in one day.
Dave the runner
San Jose, CA
6 years ago
Verified Buyer
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Just what I needed!
Exactly what I needed to use my millivolt thermostat
with a 24 volt WiFi unit. The ordering, shipping and arrival was flawless, couldn't have gone better!
Joe G.
NH
6 years ago
Verified Buyer
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Works as intended
Fast shipping, product used to get a Nest to work with two wire system. Works flawlessly.
JJaocbs
Vermont
7 years ago
Verified Buyer
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Helped get my nest up and running
Great product! Definitely helped install a nest thermostat in an old millivolt system. One of the screws, however, was bent.
Home owner
Connecticut
8 years ago
Verified Buyer
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Exactly what I needed
Used this to hook up my millivolt pellet stove to my nest. Worked just as I expected. Highly recommend.
astetson
North Reading, MA
8 years ago
Verified Buyer
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Product Q&A
6 Questions6 Questions
Q: I am trying to control a grundfos circulating pump with my thermostat from the house. I still have the 2 wires in the basement that connect to the thermostat, but the the old 24 volt transformer was removed with the old boiler when basement flooded. Do I need a 24 volt transformer for the thermostat or can I connect thermostat to this unit and regulate the 120v pump?
Asked by Marcel 11 years ago
Add your answer
Verified Reply- Supplyhouse StaffYes, you can power and connect a 24V thermostat with this relay.
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Q: How do you wire this switch relay to a Uponor 519 thermostat? The switcher calls for heat all the time. This is installed on garage radiant heat floor, using the floor sensor with thermostat.
Asked by Dave 11 years ago
Add your answer
Verified Reply- Supplyhouse StaffBelow is linked the install instructions for that relay: http://s3.supplyhouse.com/product_files/R8845U1003-Install.pdf
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Q: I have 4 zone valves running off one circulator I was told I can run all of them with this relay box
Asked by 14 years ago
Add your answer
Verified Reply- PexSupply StaffWe'd recommend a Taco ZVC404 or ZVC404-EXP (the -EXP version is "expandable" and can be combined with other -EXP controls).
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Q: I have 4 zones. Do I need 4 switching relays 0r will this control 4 zones?
Asked by 15 years ago
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Verified Reply- PexSupply StaffThis can only control one zone, so you would need 4 switching relays. Another option would be to use the Taco SR504 switching relay, which can accommodate four zones.
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Q: when I connect lines 1 and 2, and jump r-w on a switching relay (honeywell R8845U) should I get 24V on X1-X2, also 120v should come out to connect circulator pump?
Asked by Fred 15 years ago
Add your answer
Verified Reply- PexSupply StaffNo, the X1 and X2 are dry, low-voltage rated contacts. A circulator may be wired to either COM and NO or to A and B, as both of these are line voltage rated contacts. They are also dry contacts.
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Q: can you control 2 heating zone valves and 1 circulator pump with this control ?
Asked by hubby 16 years ago
Add your answer
Verified Reply- PexSupply StaffNo, you cannot. For that application, you need the Taco ZVC403-2.
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