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Z

Zero KST203 Water Heater Thermostat,Upper Thermostat,UL certification,Black

  • Based on 64 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Wednesday, Sep 30
Order within 8 hours and 30 minutes
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Color: Kst203


Features

  • Double Throw, 120/480 VAC,for dual element tanks
  • Energy saving range setting
  • Built in safety switch to prevent overheating
  • Cross-reference:59T SPDT+66T
  • All thermostats are adjustable,UL certification

Description

ZERO HVAC is specialist in offering solution in refrigeration. We can provide integral cold room system's design,completed spare parts for air cooler, condensing unit, refrigerator and air conditioner.Meanwhile,water heater thermostat, fittings and tools used in installation project are also available in ZERO HVAC. Most of product are certificated with UL,TUV. We also can customize product according to customer specific requirement. HAZARD OF ELECTRICAL SHOCK! Before removing any access panels of servicing the water heater, make sure the electric supply to the water heater is turned “OFF”. Failure to do this could result in DEATH, SERIOUS BODILY INJURY OR PROPERTY DAMAGE. Failure to place the thermostat behind the thermostat bracket and against the tank could cause overheating resulting in DEATH, SERIOUS BODILY INJURY OR PROPERTY DAMAGE. KST203 SERIES controls are designed to meet the high electrical capacity requirements of electric water heaters. The speed and force of contact separation provides long-dependable control life at high electrical loads.Approval: UL,CUL High quality home appliance accessories make your life easier and better! WHY CHOOSE US We have rich experience in home appliances, HVAC applications and automotive thermal control technology, and develop products and solutions. HIGH QUALITY SERVICE If you are not satisfied with the product for any reason, please feel free to contact zero through Amazon, and we will be happy to serve you! We focus on innovative technology, improving product quality, practical solution development and automated manufacturing. Our components have strict process control and quality testing, as well as all major certification and environmental safety compliance. We have our own factory. Our products will undergo strict quality inspection before leaving the factory to ensure quality. Because our products can bring more convenience and happiness to your life. Single Electric Water Heater Thermostat

Brand: Z


Controller Type: Push Button


Special Feature: Portable


Color: Kst203


Specific Uses For Product: Heater


Controller Type: Push Button


Additional Features: Portable


Specific Uses For Product: Heater


Temperature Control Type: digital


Connectivity Technology: Z-Wave


Power Source: Battery Powered


Voltage: 480 volts


Display Type: digital


Control Type: Button Control


Control Method: Touch


Connectivity Protocol: Z-Wave


Mounting Type: Surface Mount


Wattage: 120 watts


Item Weight: 0.17 kg


Brand Name: Z


Included Components: Safety Switch, Relay


Model Number: KSD203


UPC: 611864965512


Manufacturer: Longterm


Number of Items: 1


Manufacturer Part Number: KSD203


Color: Kst203


Shape: Rectangular


Product Style: Indoor Installation


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, Sep 30

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • Zip Pay in 4
  • Financing through Apple Pay
  • Financing through Google Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


  • Exactly as described!
Color: Kst203
Worked great! but our waterheater was leaking, so we threw it out.
Reviewed in the United States on April 1, 2026 by Help

  • Just like OEM
Color: Kst203
This is a durable replacement to the OEM units. Easy to install and have not had any fail
Reviewed in the United States on March 21, 2026 by Jennifer B

  • Please delete this review.
Color: Kst203
Lasted only a year before the lower element stopped heating.
Reviewed in the United States on November 20, 2025 by Nate

  • Needed it
Color: Kst203
Arrived quickly and works well
Reviewed in the United States on July 31, 2024 by Belgath

  • Fits perfectly
Color: Kst203
It fixed my hot water and fit perfectly
Reviewed in the United States on January 5, 2025 by Brad Damron

  • shipped on time and worked
Color: Kst203
shipped on time and worked
Reviewed in the United States on November 19, 2024 by john carnes

  • Cost is a lot better than the rest and there the same
Color: Kst203
Not a darn thing it was great and I got hot water..bless u.
Reviewed in the United States on April 29, 2024 by Henry earl Adams

  • Works
Color: Kst203
Direct replacement and its been working fine for a few months.
Reviewed in the United States on December 23, 2022 by E 💘 T

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