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$169.59 each
In Stock
Get 17 Tomorrow, Jul 2
Order by 6PM, receive Tomorrow
MANUALS (1)
This item replaces: MC-100V-1S, MC-91-2W
Free Shipping This item ships free
Easy Returns No restocking fee for 90 days
Product Highlights
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White
Description
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Rinnai MC-601-W White Controller
A wired temperature controller accessory for compatible Rinnai tankless water heaters, used to adjust temperature, set parameters, and run diagnostics from a convenient indoor location.
Key Features:
Compatibility & Applications:
Installation & Operation Notes:
Maintenance & Troubleshooting:
User Reviews & Q&A Summary:
A wired temperature controller accessory for compatible Rinnai tankless water heaters, used to adjust temperature, set parameters, and run diagnostics from a convenient indoor location.
Key Features:
- Accessory controller for Rinnai tankless water heaters used to adjust temperature, set parameters, or run diagnostics
- Up to four controllers may be connected for added convenience
- Color: White (listing/manufacturer)
- This item replaces: MC-100V-1S, MC-91-2W (listing)
- Physical dimensions (manufacturer specs): 5" depth x 3.5" width x 1" height; 0.2 lb
Compatibility & Applications:
- Intended to pair with a Rinnai tankless water heater
- SupplyHouse Q&A confirms compatibility for:
- Rinnai RE199e
- A user asking about Rinnai RUCS 651LP was told this controller will replace the MC-91-2S controller
- Must only be used where the manufacturer specifies this exact part number: MC-601-W
Installation & Operation Notes:
- Professional installation is recommended (manufacturer)
- Installation should be performed by a qualified service professional and should follow the tankless water heater's service/installation manual and the controller's install instructions
- Review/Q&A notes from the product page:
- Installation commonly involves running a two-wire connection
- Users note the wiring does not have a positive/negative orientation requirement (reviewer experience)
- One reviewer noted their package included the cable that plugs into the control board on the water heater
- One reviewer wished it included four crimp connectors instead of two (packaging expectation)
Maintenance & Troubleshooting:
- This controller is typically replaced or added when:
- A homeowner wants indoor control and easier adjustments instead of using the heater's onboard interface (review-reported use)
- Upgrading to a newer Rinnai tankless model that uses this controller (review-reported use)
- If the controller doesn't function after installation, follow the heater/controller documentation to confirm wiring and compatibility for the specific model and existing controller type
User Reviews & Q&A Summary:
- Reviews (general themes):
- Most describe it as easy to install, working as expected, and useful for adding convenient control on a main living level
- Several call out fast shipping and receiving the correct manufacturer-recommended part
- Mixed feedback on included installation details: one reviewer felt the instructions didn't clearly mention the non-polarized wiring and noted difficulty getting phone support
- Some users mention temperature-limiting behavior in their setup (one review states they wished it could go below 115°F; another review claims a 120°F max in their experience)
- Q&A highlights:
- Compatibility confirmations (e.g., RE199e)
- Max setpoint question: SupplyHouse staff states the maximum temperature setting is 140°F
Specs
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| Product Type: | Controller |
|---|---|
| Color: | White |
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Product Reviews
4.75 out of 20 reviews
95% would recommend this product
5 star
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Most Liked Positive Review
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Nice accessory to control water heater
Aside from running a two-wire circuit, it is an easy install. My only complaint is the installation instructions fail to mention that there is no positive or negare requirement when connecting the wires to the control board. I was fairly certain there was no +/- orientation, but I called Rennai customer service to confirm. The wait time was quite long. The person who answered the phone claimed he could not provide technical assistance. I called a second time and endured another long wait. Luckily, I got an answer on my second try.
The controller is a good product, but Rennai could do better job with documentation and customer assistance.
VS
Most Liked Negative Review
I would not buy this again
The Max heat is 120 and minimum is 115 I needed it to go down to 98 degrees because the unit works on flow.
Showing 1-10 of 20 reviews
What was sent was what we wanted.
The part number recommended by the manufacture was on hand, sent, and handled by SupplyHouse with speed and accuracy.
What else could I ask? Outstanding service. Thank you. I'll be back for more from SupplyHouse.
Jungle Daddy
Forest, Mississippi
1 years ago
Verified Buyer
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I would buy it again if needed.
At this moment it is working as I thought it would. It would have been nice if it came with 4 crimp connectors instead of 2.
Marc
Gainesville, TX
2 years ago
Verified Buyer
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Exactly what I needed to add indoor control of water heater
Product was exactly as described and came with everything I needed to connect to my water heater, including the 3 pin cable that plugs into the control board on the water heater.
AJ
Madison Al.
2 years ago
Verified Buyer
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Great price, fast shipping
Upgraded an old Rinnai water heater and needed the new controller to match the new model. Ordered Monday at noon and was delivered Tuesday pm. Great price : 35 % less than local stores!
Gracie
College Station TX
2 years ago
Verified Buyer
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Good Product
We use this to reduce the temperature of the hot water. It works as described. We wish it would go lower than 115 degrees, but that's the nature of the beast.
Olan
Monticello, FL
2 years ago
Verified Buyer
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I would buy this product again
The hot water heater is located in my basement and I installed the controller on the main level. It was very easy to install.
FJ
Vienna Virginia
2 years ago
Verified Buyer
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So far so good
Connects to my Rinnai V53DeP on demand heater and setup was simple
Anto
Trinidad, Colorado
3 years ago
Verified Buyer
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Easy to install and performs as advertised
Easy to install to replace an existing remote control unit in an older model Rinnai tankless water heater.
RAP
South Carolina
3 years ago
Verified Buyer
Was this review helpful to you?
Nice accessory to control water heater
Aside from running a two-wire circuit, it is an easy install. My only complaint is the installation instructions fail to mention that there is no positive or negare requirement when connecting the wires to the control board. I was fairly certain there was no +/- orientation, but I called Rennai customer service to confirm. The wait time was quite long. The person who answered the phone claimed he could not provide technical assistance. I called a second time and endured another long wait. Luckily, I got an answer on my second try.
The controller is a good product, but Rennai could do better job with documentation and customer assistance.
JJ
Central TX
3 years ago
Verified Buyer
Was this review helpful to you?
Would buy again
Working great, no issues, fast shipping!
cstrn
MS
3 years ago
Verified Buyer
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Product Q&A
3 Questions3 Questions
Q: Is this controller compatable with my Rinnai RUCS 651lp heater?
Asked by Di 2 years ago
Add your answer
Verified Reply- SupplyHouse StaffHello, thanks for writing in. Yes, this will replace the Rinnai MC-91-2S controller.
Was this review helpful to you?
Q: Does this work with the Rinnai RE199e?
Asked by Alex 2 years ago
Add your answer
Verified Reply- SupplyHouseHi Alex! Yes, the MC-601-W is compatible with your RE199e.
Was this review helpful to you?
Q: What is the max temperature that can be set with the controller. Another user in this thread mentioned that the max is 120F, but that is the default setting.
Asked by Kay 3 years ago
Add your answer
Verified Reply- SupplyHouse StaffHi Kay. The max temperature setting on this controller is 140 degrees F.
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