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Model#: RHMNRTG20124

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Brand new items;Full manufacturer warranty available
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Rheem RTG20124 Tankless Water Heater Flushing Kit

  • Rheem RTG20124 Tankless Water Heater Flushing Kit
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  • Helps maintain the performance of your Rheem tankless water heater
  • Connects easily to tankless isolation valves
  • Rheem's Tankless Water Heater Flushing Kit should prolong the life of your tankless water heater.
  • For use with all tankless models
  • This item may ship in the original manufacturer's packaging.
  • Tankless Water Heater Flushing Kit - RTG20124
  • (1) 5 Gallon Bucket
  • (1) Submerisible Pump
  • (2) Rubber Hoses
  • (1) Instruction Sheet
Compliance and Restrictions
warning: Cancer and Reproductive Harm --


Compatible With: Tankless Models



4.6 / 5.0
5 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
Yes, I would recommend this to a friend (3)
Excellent quality. Easy to use and includes great instructions
January 19, 2019
Great kit, works perfectly, good price.
This is a complete flushing kit (except for the vinegar you'll need), ready to go. Works great and frankly, considering the high quality of the included pump & the amount a service company would have charged to come do the job, this is very reasonably priced. I highly recommend it.
March 28, 2018
Yes, I would recommend this to a friend
Useful kit of parts
This is a convenient collection of off the shelf parts. It consists of a bucket (like the orange ones Home Depot sells) a Franklin UP16M 1/6 HP submersible pump and two washing machine hoses.

Add two gallons of white vinegar. Connect one hose from the pump to the cold service valve on your tankless heater and the other one from the hot service valve to drain back into the bucket. Set the valves and run for 45 min to an hour. That's it.

To purge the vinegar, relocate the "hot" hose to a drain and restore just the cold service valve to normal. Let it run for five minutes. Only then restore the hot valve to normal.
October 8, 2014
Yes, I would recommend this to a friend
Easy as boiling water
Fast and easy to use
March 29, 2012
Yes, I would recommend this to a friend
Great Kit
Works great for flushing out a tankless water heater. Very nice kit.
November 11, 2011

Questions & Answers

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Browse 3 questions Browse 3 questions and 4 answers
How long are the hoses
wendy on Jan 11, 2013
BEST ANSWER: The hose is 12 inches long but larger ones can be attached.
How often should this be used on your water heater?
Julie on Feb 19, 2015
BEST ANSWER: Flushing the tank once per year to remove mineral deposits is recommended.
Do I need isolator valves on this tankless unit to use this cleaner
car on Jul 29, 2013
BEST ANSWER: Yes, this flush kit is easy to use and connects to tankless isolation valves.