Five outdoor models. Different flow rates, different burner ratings, the same no-vent install. This guide compares the full Rheem outdoor lineup — RTG-64 through RTG-95, plus the RTGH-95 Prestige condensing — so you can pick the right size before the truck rolls.
Compare GPM, BTU, and bathroom-count fit, then jump to the model page that matches.
Maximum flow rate at 35°F temperature rise
Every Rheem outdoor tankless installs without venting and includes built-in freeze protection down to -30°F (with power). The differences that drive sizing are flow capacity, BTU input, and efficiency class.
For the cabin, the in-law unit, the one-and-a-half bath bungalow.
The dependable middle. Two bathrooms and the dishwasher running.
The all-rounder. Three baths, back-to-back showers, no theatrics.
Big house, cold climate, no patience for the second-shower wait.
Same flow as the RTG-95 — condensing efficiency, EcoNet-ready.
Skip the homework. Find the situation that sounds like yours and start there.
Low simultaneous demand, occasional use, often propane. The RTG-64 is purpose-built for this — small footprint, lowest BTU draw, no venting headache.
Florida, Texas, the Carolinas. Inlet temps stay above 60°F most of the year, so a mid-size unit hits its rated flow. The RTG-70 or RTG-84 is the sweet spot.
Midwest or Mountain West. Inlet can drop to 40°F in January. You'll need a 77°F rise and 5+ GPM at that rise — only the 9.5 GPM units deliver.
Going outdoor frees up a closet and skips the venting bill. Match flow to your old tank's recovery: a 50-gallon equivalent is RTG-84, larger families step up to the RTG-95.
If you plan to stay 10+ years and your utility offers condensing rebates, the RTGH-95 Prestige pays back the premium through lower fuel draw and federal tax credit eligibility.
Every model in this lineup has a propane variant — same chassis, same BTU, just dialed for LP. Match the model to your bathroom count, then swap the suffix from N to P.
RheemTanklessOnline.com is operated by LCP Supply alongside our flagship plumbing wholesale site, PlumbersCrib.com. Every order is fulfilled by PlumbersCrib — an authorized Rheem dealer with full manufacturer warranty support. Talk to us before you order. Proper sizing is the difference between a happy install and a callback. Call 877-881-2742 and we'll walk through inlet temperature, fixture count, and your fuel situation in five minutes.