Search  for anything...

Romalon 42001-0053S Heater Thermistor Stainless Steel for Pool Heater Parts Replacement Pool and Spa Heater

  • Based on 91 reviews
Condition: New
Checking for product changes
$14.77 Why this price?
Holiday Deal · 30% off was $20.99

Buy Now, Pay Later


As low as $3 / mo
  • – 4-month term
  • – No impact on credit
  • – Instant approval decision
  • – Secure and straightforward checkout

Ready to go? Add this product to your cart and select a plan during checkout. Payment plans are offered through our trusted finance partners Klarna, PayTomorrow, Affirm, Afterpay, Apple Pay, and PayPal. No-credit-needed leasing options through Acima may also be available at checkout.

Learn more about financing & leasing here.

Free shipping on this product

Eligible for Return, Refund or Replacement within 30 days of receipt

To qualify for a full refund, items must be returned in their original, unused condition. If an item is returned in a used, damaged, or materially different state, you may be granted a partial refund.

To initiate a return, please visit our Returns Center.

View our full returns policy here.


Availability: Only 5 left in stock, order soon!
Fulfilled by Amazon

Arrives Sunday, Dec 29
Order within 14 hours and 52 minutes
Available payment plans shown during checkout

Features

  • PART NUMBER: 42001-0053S Thermistor Compatible with pool and spa heaters.
  • Replacement for pool and spa heaters electrical system.
  • Kit for Part Number 42001-0053S.
  • This part is made from durable high quality material and the performance is tested to meet OEM product.
  • Package includes 1pc of 42001-0053S Thermistor.

Package Dimensions: 3.5 x 2.1 x 0.3 inches


Item Weight: 1.76 ounces


Manufacturer: Romalon


Item model number: 42001-0053S


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Dec 29

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
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


  • Easy to install - solve Mastertemp 400 heater error code e01 (open temp resistor)
Easy to install. I replaced the control board. Got error code e01. Replaced the thermistor (open temp resistor) as someone recommended. The top one is the inlet water temp resistor to replace. Took me less than 20 min. to finish. The heater is running again.
Reviewed in the United States on December 16, 2020 by Amazon Customer

  • The Romalon Heater Thermistor fit my Pentair pool heater and works great.
The Romalon Heater Thermistor fit my Pentair pool heater and works great. Great price and super fast delivery. The original thermistor failed after 7 years and the heater would not heat. Now it works like it should. Great product.
Reviewed in the United States on November 28, 2022 by SanJan

  • Good price and function
Thermistor worked perfectly in my Hayward pool heater. Easy install and works flawlessly along with a good price
Reviewed in the United States on March 23, 2024 by jeff in NY

  • Fixed our pool heater - let summer begin!
This tiny, inexpensive piece was the key to fixing our pool heater! It was shipped in a reasonable amount of time and much cheaper than hiring someone to fix the heater.
Reviewed in the United States on June 27, 2020 by Supa Momma G

  • Did the trick
Easy to install, and saved me hundreds. Any pool equipment repair person would charge $300+ to fix.
Reviewed in the United States on May 22, 2020 by Brian

  • Great!
Works great.
Reviewed in the United States on July 14, 2021 by Amazon Customer

  • Perfect replacement part
This thermistor is exactly what I needed to fix my pool heater. It was easy to install and was an exact replacement.
Reviewed in the United States on June 8, 2020 by Tim E.

  • Easy to install!
Easy to Install saved me $$$$
Reviewed in the United States on June 24, 2021 by Chicago Girl

Can't find a product?

Find it on Amazon first, then paste the link below.