Rheem RTG-84 Tankless Water Heater Reviews


Today we had a chance to look over the Rheem RTG-84 tankless water heater. As with all tankless water heater reviews, went over this unit with a fine comb. The Rheem RTG line is their mid-efficiency line. We did a review on their high efficiency line here. The RTG line comes in 3 sizes: 199,900 BTU, 180,000 BTU and 150,000 BTU. All 3 models can burn natural gas or liquid propane. Also, these series is offered in a indoor or outdoor option.


What we likes about the Rheem RTG-84

1. The price point. The current street value is around $750-$800. This is a very fair value for the unit.


2. This unit and all the other Rheem gas units have minimum flow rate of 0.26 GPM. You do need to exceed a flow rate of 0.40 GPM to activate the unit, then can turn the water back down to where you need it.


3. The unit is high altitude compliant up to 9,840 ft.


4. The units have freeze protection for down to -30ºF. Now that is cold!


5. There is a 12 year warranty on the heat exchanger and 5 year on parts and 1 year on labor. This is for residential installs.


6. While this might not be for the average home owner. The unit can be upgraded to have a temperature range of 85ºF-185ºF (Note: we do not recommend running a unit this hot as it can burn skin instantly)


7. Rheem has a technology called EZ-Link™, which allows 2 units to be hooked up together and function like one unit.


8. The burn is conveniently located and will be easy to service, if needed.


What we didn’t like about the Rheem RTG-84

There isn’t much we didn’t like about this unit when comparing it to like models in its class.


1. The GPM at 77 ºF is 3.9 GPM. While this isn’t bad, we just think it could be a little better in our opinion.


2. Again, like the other Rheem products the max temperature is set to 120 ºF. It can be changed in the field to a max of 140 ºF. We still hate this!


3. No scale build up detector for the home owner to know when to have the unit serviced.


If you are on a budget or going to be selling your house soon, this might be a good option for you. The price point is right and it does have some solid features.


Rheem RTG-84 tankless water heater:

  • Min Gas Consumption Btu/h – 11,000
  • Max Gas Consumption Btu/h – 180,000
  • Water Capacity GPM Activation – .4
  • Water Capacity GPM Min -.26
  • Water Capacity GPM Max – 8.4
  • TemperatureRange  – 85 ° to 140 ° (option to upgrade to 85 ° to 185 °)
  • Gas Supply Connection – 3/4 inch MNPT
  • Cold Water Input Connection – 3/4 inch
  • Hot Water Input Connection – 3/4 inch
  • Weight -82 lbs
  • Dimensions 25.625” x 13.875” x 9.875” (H x W x D)
  • 5 year parts and labor warranty
  • 1 year labor warranty
  • 12 year heat exchange warranty

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Rheem RTG-84
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