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Model#: RHMNRTE-18
Condition:
New

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New
Brand new items;Full manufacturer warranty available
Reconditioned
Manufacturer inspected, repaired and tested items; CPO 60 day money back guarantee
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Returned items inspected, repaired and tested by CPO technicians; CPO 60 day money back guarantee

Rheem RTE-18 Electric Tankless Water Heater - 18 kW

  • Rheem RTE-18 Electric Tankless Water Heater - 18 kW
List:
$549.99
Sale Price:
$449.99
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Product Overview

Additional Information

Details

Continuous, on demand, hot water and a compact design means this Electric Tankless Water Heater is perfect for point-of-use applications.
Features:
  • Can heat a maximum of 5 gallons per minute
  • Energy efficient when compared to traditional water heaters
  • On-unit temperature control
  • LEDs indicate active element and standby mode
  • Standard 1/2 in. water connection
  • Rugged brass/copper heat exchanger
  • Great for homes, condos, hospitals, boats, offices, laboratories, and anywhere hot water is needed
Includes:
  • 18 kW Electric Tankless Water Heater - RTE-18

Specifications

Weight: 12 lbs.
Activation Flow: 0.40 GPM
Amperage: 75
Application: Point-Of-Use
Kilowatts: 18
Required Breaker: (2) 40 Amp
Water Connection: 1/2 in. NPT
Wire Size: (2) 8 Gauge

Recommendations

Reviews

4.1 / 5.0
8 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
2
5
1
0
0
Would you recommend?
Yes (6)
No (1)
Recommendations
No, I would not recommend this to a friend
Ok heater after painful exchange process
We chose this model to to provide warmish water in winter and hot water in summer to our sink in a New England horse barn. The half inch copper pipe run is only six insulated, interior feet from heater to sink, and we have brand new 8-gauge wiring to 2x40 amp breakers in a new 200 amp panel 20 feet away. When we first turned it on at 3+ GPM there was no discernible rise in temperature above 45 degrees. Only after throttling down to below 1.5 GPM could we get a 35 degree temperature rise. My electrician says the interior heating elements looked like it was a refurb gone wrong. The first unit was clearly defective, but we could not get any of several people at Rheem to admit it to me, my electrician, or my plumber over several phone calls. Only after much further haggling and jumping through hoops with Rheem and some help from CPO was I able to negotiate a replacement. The second unit was shipped quickly by CPO, but there was some warping or bending to the front panel so that it fits poorly on the main housing. My electrician suspected another refurb. Otherwise the second RT-18 works about as expected at nearly the specified rise and flow to provide adequately warm water in winter. No way can my particular unit supply more than one sink at a time in our location in February, but we expected no more than that. We would buy another product from CPO again, but not Rheem. From our perspective Rheem's customer service efforts were geared toward preventing a legitimate return rather than satisfying the customer. After too many hours already wasted it's just easier to live with a less than perfect second unit rather than pay my electrician and plumber yet again to roll the dice on a third unit. In an age of online reviews its very unwise of Rheem to wear down a customer rather than doing the right thing from the very beginning. At least CPO, the retailer, acted as if they understand that.
March 28, 2012
Recommendations
Yes, I would recommend this to a friend
Works Fine But a Little Slow
I recommend this product especially if you want to get rid of a tank water heater to make more room. In my case it was a laundry room. It mounts on the wall and is smaller than I thought it would be. The water gets very hot but for some reason it takes quite a bit longer for hot water to come out of the faucet than when I had the tank in there. Also, take into consideration the cost for installation. I had to run 2 bigger cables to the unit which took up 4 spaces in my breaker panel. Plumbing was simple but once again, it's an added cost.
November 30, 2011
Recommendations
Yes, I would recommend this to a friend
i wish i had this a long time ago
i have peace of mind that it is not running and wasting electricity. no rust at the bottom of a tank no leaks, no elements to replace like a tank water heater. what else can i say i love it.
November 6, 2011
Recommendations
Yes, I would recommend this to a friend
Electric Tankless Water Heater - 18 kW
Bought over-sized unit so it could do whole house if I needed to due to increaseing oil cost . Will do up-to 5 GPM , I only need it on kitchen faucet at this time at a flow of 2 GPM . Very capable unit . Fit right under my kitchen sink .Quiet and quick .
December 6, 2011
Hot but Thankless
Installed in a single-wide trailer to provide water for the shower and sinks. Works well - love having hot water! - but requires hook up to it's own 75 amp circuit.
March 27, 2014
Recommendations
Yes, I would recommend this to a friend
Excellent on-demand water heater
It lasted almost 4 years before leaking, but I'm still happy with the model. I did a lot of research before I bought the first and the RTE-18 was the best in my price range. My new one is an RTE-18 also; plug and play so to speak.
March 21, 2015
Recommendations
Yes, I would recommend this to a friend
Had one it lasted 5 yrs bought another
Works great
December 1, 2015
Recommendations
Yes, I would recommend this to a friend
THE NAME SAY'S IT ALL
HOT STUFF
November 6, 2012

Questions & Answers

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Browse 22 questions Browse 22 questions and 30 answers
Will this work in NYS where incoming village water is cold all year and colder in the winter? 1 person 1kitchen sink, 1 bathroom. Never in use at the same time. Thank you.
inquiringmind on Feb 23, 2016
BEST ANSWER: In general, yes; but it will depend on the temperature of the water coming into the water heater. If the temperature coming in is too cold, thus lowering the GPM, it may not have enough flow rate to activate the pilot to heat the water. We recommend talking to a professional installer in your area to be certain that it will work before making this purchase.
How long do they last....
Johnny on May 3, 2016
BEST ANSWER: The Applicable Warranty Periods are ten (10) years from the Effective Date for the heat exchanger and three (3) years from the Effective Date for the component parts if the water heater is installed in a single-family dwelling. If the water heater is installed anywhere other than a single-family dwelling or in any system in which the water is recirculated, the Applicable Warranty Periods will be limited to one (1) year from the Effective Date.
Why don't someone state how many volts these units need? If these are placed under the sink, do we need to run 220 volts to our sink area, most of us only have 110 at the sink area. Don't understand why this info is not in the specs.
sparky on Oct 7, 2014
BEST ANSWER: One would logically think that it is 240 volt as it states 2-40Amp What they forget to mention is that you need 2 40Amp double breakers. BIG difference!
I live in an area that can sometimes get to 0 degrees on a really cold winter day, and the average tempurature through the year is around 50 degrees. I live in a condo with two sinks and 1 shower would this unit work for me?
Jordie on Jul 14, 2016
BEST ANSWER: I feel it will work for you once the water becomes hot. You may have a
shorter run between the unit and your fixtures than we do. That will get
you your hot water quicker. It will take a bit of time to heat your water
in your climate however. It does mention temperature of water coming into
your dwelling possibly being an issue when cold outside. I live in Florida
so not an issue here.
Is the RTE18KW 110/120 or 220
tnrooster on Jul 6, 2016
BEST ANSWER: The Rheem RTE-18 uses 240 volts.
what is the cost of installation
jim on Mar 25, 2016
BEST ANSWER: Installation cost will vary. We recommend contacting local installers for a quote.
What are the dimensions of this particular unit? Maybe I just missed them in the Specs? I see weight is 12lbs
Jon on Mar 24, 2016
BEST ANSWER: The dimensions of this product are as follows: 11.2 x 11.2 x 10.5 inches.
Our cold water runs clear. When we use the Reem tankless water heater, the water runs yellowish orange. Will that go away? Do we need to flush the heater? It was installed about a month ago. Also, we were unable to find the serial number to register for warranty.
Tracey on Nov 24, 2015
BEST ANSWER: Please contact Rheem directly for tech support at 866-720-2076.
Has anyone put one in Florida? The guys that sell the tank models say it won't work in FL.
chuck on Nov 16, 2015
BEST ANSWER: Location is not as much of a concern as flow rate is. An RTE 18 will supply hot water to a shower, but it wont be able to supply to anything else at the same time.
what size would i need four a 2 bath 4 people house
Neil on Nov 13, 2015
BEST ANSWER: The RTE 28 would be recommended for applications where both showers would be used at the same time.
How many peple can shower at the time
Ed on Oct 28, 2015
BEST ANSWER: It all depends on the degree rise that the unit is needing to maintain. If the water during the winter is coming in at 50 degrees or so,the RTE-18 will be able to supply water to one shower
what fittings needed to connect water line to unit
Larry on Sep 27, 2015
BEST ANSWER: This will need standard 1/2" water connection fittings.
If the unit requires 2/double breaker 40 amp and you have 2/double breaker 50 amps, can you run the unit on the double pole 50 amps without damaging the unit?
Vonniebell on Sep 15, 2015
BEST ANSWER: For technical support, we recommend contacting Rheem directly at 1-866-720-2076.
what is maximum operating temperature? conversion rate?
David on Sep 4, 2015
BEST ANSWER: 105 degrees fahrenheit
I am looking at tankless elcctric w/heaters but do not know whay size i would need for 3/2 one store/ two adults.
Please help
ROR on Aug 28, 2015
BEST ANSWER: You will need at least a 25 kw or bigger, just in case you are running a washer and trying to shower at the same time make sure you have a minimum flow of 5 gallons per minute flow rate.
Do u still have to run a T&P valve
Dan on Aug 27, 2015
BEST ANSWER: No valve kit is needed for the Rheem Electric Tankless Water Heater - 18 kW.
I have a kitchen sink & 1 bathroom with shower and sink with one person living there. What size Electric unit will i need?

Thanks
Denny
Denny on Aug 7, 2015
BEST ANSWER: The Rheem Electric Tankless Water Heater - 18 kW will work with your application.
Thinking of using this type of water heater in one bdrm, 1 bath mobile home units (10) for elderly and/or disabled veterans. Would there be satisfactory hot water flow to handle shower, sinks, washing machine without the water running cold or just barely warm for the occupant? How would the cost of running the unit stack up against a regular water heater?
Ginny in Tn. on Jun 26, 2015
BEST ANSWER: The RTE 18 is on the low end for a unit to fit your needs. The unit will struggle in the winter, and on the further applications from the heater. It will run any single application by itself,but it will struggle to maintain the desired water temp once multiple things are run at the same time.
Is one double throw 220 volt 40 amp breaker the same as two 40 amp breakers ?
Andy on May 9, 2015
BEST ANSWER: No, the double pole breaker is 40 amps but the two poles gives it the 220V. A single pole will only provide 110V.
I'm starting my research for a Tankless Water Heater, I'm looking at Rheem since it is a recognized brand for a/cs. Looking at the RT-18, we have a 3 bedroom, 2.5 bath , 2 story townhome. Only 2 adults occupying, would the RT-18 be enough ?
Pat on May 7, 2015
BEST ANSWER: With a 5gpm max flowrate given the best possible case in terms of water temp before the unit has to heat it, the RTE-18 is going to be a bare minimum in terms of KW.
Do you sell parts for this heater? We installed one in February and are having trouble with it over heating and tripping the eco. The power keeps running after the water is turned off, and thought it might be the temperature control box.
Wayne on Dec 9, 2014
BEST ANSWER: Please contact Rheem directly at 866-720-2076 for parts.
my home is a 2 bath and I have 4 b.r. Have 3 kids and 2 adults. what size is ok...
Harvey on Nov 20, 2014
BEST ANSWER: With 2 baths and 5 residents I would recommend nothing smaller than the RTE-18, a safe bet would be the RTE-27.

Warranty

LIMITED WARRANTY
RHEEM® or RUUD® Residential Tankless Gas Water Heaters

GENERAL

This Limited Warranty is only available to the original owner of this water heater. It is not transferable. Rheem Manufacturing Company (Rheem) warrants this Rheem or Ruud water heater, and its component parts, to be free from defects in materials and workmanship, under normal use and service, for the Applicable Warranty Period. At its option, Rheem will repair or replace the defective water heater, or defective component part(s), in accordance with the terms of this Limited Warranty, if it fails in normal use and service during the Applicable Warranty Period. The replacement water heater must be manufactured by Rheem. The replacement component part(s) must be Rheem authorized component part(s). The replacement unit will be warranted only for the unexpired portion of the original unit's Applicable Warranty Period.

EFFECTIVE DATE

The Effective Date of warranty coverage (or the beginning of the Applicable Warranty Periods) is the date of installation of the water heater, if properly documented. Otherwise, it is the date of manufacture of the water heater plus ninety (90) days.

APPLICABLE WARRANTY PERIODS

The Applicable Warranty Periods are ten (10) years from the Effective Date for the heat exchanger and three (3) years from the Effective Date for the component parts if the water heater is installed in a single-family dwelling. If the water heater is installed anywhere other than a single-family dwelling or in any system in which the water is recirculated, the Applicable Warranty Periods will be limited to one (1) year from the Effective Date.

APPLICABLE WARRANTY PERIODS FOR PURCHASES AFTER 7/1/08 or a 53, 66, or 74 Model Rheem Tankless Water Heater

The Applicable Warranty Periods are twelve (12) years from the Effective Date for the heat exchanger and five (5) years from the Effective Date for the component parts if the water heater is installed in a single-family dwelling. If the water heater is installed anywhere other than a single-family dwelling or in any system in which the water is recirculated, the Applicable Warranty Periods will be limited to one (1) year from the Effective Date.

APPLICABLE WARRANTY PERIODS FOR PURCHASES BEFORE 7/1/08 or a 42 Model Rheem Tankless Water Heater

The Applicable Warranty Periods are twelve (12) years from the Effective Date for the heat exchanger and five (5) years from the Effective Date for the component parts if the water heater is installed in a single-family dwelling. If the water heater is installed anywhere other than a single-family dwelling or in any system in which the water is recirculated, the Applicable Warranty Periods will be limited to one (1) year from the Effective Date.

All Applicable Warranties will be limited to three (3) years from the Effective Date if the water heater is installed in a system in which the water is re-circulated, but not if its an on-demand re-circulation system which utilizes existing hot and cold water lines, or a dedicated return line without the use of a temperature sensor, timer, or a continuously operating pump

All Applicable Warranties will be limited to three (1) year from the effective date if the water heater is installed anwhere other than a single-family dwelling.

WARRANTY EXCLUSIONS

This Limited Warranty will not cover:

  1. Service trips to your home to teach you how to install, use, or maintain this water heater or to bring the water heater installation into compliance with local building codes and regulations.
  2. This residential tankless water heater if it is installed for use in: spa or pool heating; a mobile home; a recreational vehicle; a boat or any other watercraft.
  3. Units installed in any circulating system in which the temperature of the incoming water to the water heater is in excess of 120° F.
  4. Damages, malfunctions or failures resulting from failure to install the water heater in accordance with applicable building codes/ordinances or good plumbing and electrical trade practices.
  5. Damages, malfunctions or failures resulting from improper installation or failure to operate and maintain the unit in accordance with the manufacturer's instructions provided, including outside of recommended water quality levels as listed in the chart below:
  6. Performance problems caused by improper sizing of the water heater or the gas supply line, the venting connection, combustion air openings, electric service voltage, wiring, or fusing.
  7. Damages, malfunctions or failures caused by improper conversion from natural gas to LP gas or LP gas to natural gas fuel source.
  8. Damages, malfunctions or failures caused by operating the water heater with any parts removed or with modified, altered, or unapproved parts installed.
  9. Damages, malfunctions or failures caused by abuse, accident, fire, flood, freeze, lightning, acts of God and the like.
  10. Heat exchanger failures (leaks) caused by operating the water heater in a corrosive or contaminated atmosphere or damages, malfunctions or failures caused by lime or mineral build-up.
  11. Damages, malfunctions or failures caused by operating the unit at water temperatures exceeding the maximum setting of the operating, or high limit, control.
  12. Heat exchanger failures caused by operating the water heater when it is not supplied with potable water.
  13. Damages, malfunctions or failures caused by subjecting the heat exchanger to pressures, or firing rates, greater than those shown on the rating label.
  14. Damages, malfunctions or failures resulting from the use of any attachment, including any energy saving device, not authorized by Rheem.
  15. Units installed outside the fifty states (and the District of Columbia) of the United States of America and the Dominion of Canada.
  16. Units removed from the original installation location and reinstalled elsewhere.
  17. Units that have had their rating labels altered, tampered with, or removed. A water heater should not be operated if the rating label is removed.

LABOR, SHIPPING, AND PROCESSING COSTS

This Limited Warranty does not cover any labor expenses for service, repairs, reinstallation, permits, or removal and disposal of the failed water heater, or defective component part(s). All such expenses are your responsibility. Rheem will pay the transportation costs for an “in-warranty” replacement water heater, or “in-warranty” replacement component part(s), to a convenient delivery point (selected by Rheem) near the place the original water heater, or original component part(s), is located: such as a local Rheem or Ruud water heater distributor.You must pay any local freight charges, including the cost of returning the failed water heater, or defective component part(s) to a convenient shipping location (selected by Rheem): such as a local Rheem or Ruud water heater distributor. Rheem does not authorize, recommend, or receive any benefit from any claims processing or similar fees charged by others to process warranty claims for any Rheem or Ruud water heater or component part(s). Rheem will not reimburse any party for these, or any other, fees not specifically covered in this Limited Warranty document.

HOW TO OBTAIN WARRANTY CLAIM ASSISTANCE

Any claim for warranty assistance must be made promptly. First, determine if your water heater is “in-warranty” (that is, within the Applicable Warranty Period).You can determine your unit's warranty status by adding its Applicable Warranty Period to its date of installation. However, if you do not have documentary proof of your water heater's date of installation, your unit's warranty status will be based on its date of manufacture. The first four digits of the unit's serial number represent the month and year it was manufactured. Add the Applicable Warranty Period plus ninety (90) days to the date of manufacture to determine whether the water heater is still covered by this Limited Warranty.You may also determine your unit's warranty status by obtaining the complete model number, complete serial number, and date of installation of your water heater and then accessing the “Warranty Verification” information on Rheem Water Heaters' internet website (www.rheem.com) or contacting Rheem Water Heaters' Claims Department (telephone (800) 621-5622) during normal business hours (in the Central Time Zone) to determine if the Applicable Warranty Period has expired. If your water heater is “in-warranty”, contact the plumber, or mechanical contractor, that installed it for assistance with the warranty repairs, or replacement, required.You may also select a plumber, or mechanical contractor, from your local Yellow Pages to assist you. Rheem Water Heaters' Technical Service personnel are available to assist you (by telephone at (800) 432-8373 or via e-mail at techserv@rheem.com) in obtaining “in-warranty” service or to answer your questions about the operation or repair of your water heater during normal business hours (in the Central Time Zone). Be prepared to provide the plumber, mechanical contractor, or Rheem Technical Service person you call with the complete model number, the complete serial number, and the date of installation of your water heater in addition to an explanation of your water heater problem. If an exact replacement is not available, Rheem will provide you with the current model of your water heater, or component part(s), or a replacement unit with comparable operating features. If government regulations or industry certification or similar standards require the replacement water heater, or replacement component part(s), to have features not found in the defective water heater, or the defective component part(s), you will be charged for the difference in price represented by those required features. If you pay the price difference for those required features and/or to upgrade the size and/or other features available on a replacement new water heater, you will also receive a complete new Limited Warranty (with the full Applicable Warranty Periods) for the replacement new water heater. Rheem reserves the right to inspect, or require the return of, the failed water heater or the defective component part(s). Each “in-warranty” failure water heater must be made available to Rheem (with the rating label and all the component parts intact) in exchange for the replacement water heater. Each defective “in-warranty” component part to be replaced must be returned to Rheem in exchange for the replacement component part. Warranty compensation is subject to validation of “in-warranty” coverage by Rheem Claims Department personnel.

  • To obtain warranty compensation for an “in-warranty” water heater failure, you must provide Rheem with: (at Rheem's option) either the failed water heater (with the rating label and all the component parts intact) or the complete original rating label (photocopies are not acceptable) removed from the failed water heater; the complete model number and the complete serial number of the Rheem or Ruud water heater that replaced the failed unit; and the date the original water heater failed.You may also be required to provide documentary proof of the failed water heater's date of installation to establish its “in-warranty” status.
  • To receive warranty compensation for an “in-warranty” defective component part, you must provide Rheem with: the defective component part; the complete model number and the complete serial number of the Rheem or Ruud water heater from which the defective component part was removed; and the date the defective component part failed.You may also be required to provide documentary proof of the date of installation of the Rheem or Ruud water heater from which the defective part was removed — or the date of purchase of the part (if it was purchased separately) — to establish the “in-warranty” status of the defective component part.
Warranty claim documentation should be mailed promptly to
Rheem Water Heaters, Claims Department
2600 Gunter Park Drive East
Montgomery, Alabama 36109