A tall 40-gallon propane tank for an atmospheric installation
The Rheem PROG40-36P RH62 is a Professional Classic atmospheric water heater built for propane (LP). It uses a 36,000 BTU/h burner and a natural-draft vent with a factory draft hood. Its 19½-inch tank diameter can make it worth considering where a wider tank would be difficult to accommodate, provided there is enough height and proper venting.
For a replacement in Palm Beach Gardens, Jupiter or nearby communities, WHE checks the existing installation and the household’s hot-water demand before recommending a model. Two heaters labeled “40 gallon” can differ in burner input, delivery, dimensions and vent requirements.
Verified capacity and performance
| Nominal capacity / rated storage | 40 gallons / 38 gallons |
|---|---|
| Fuel and burner input | Propane (LP), 36,000 BTU/h |
| Uniform Energy Factor | 0.66 UEF |
| First-hour rating | 84 gallons |
| Recovery at a 90°F temperature rise | 36.3 gallons per hour |
| Standard manufacturer warranty | Six-year limited tank and parts warranty |
The tank holds 38 gallons of rated storage within the 40-gallon nominal class. Its 84-gallon first-hour rating is a tested delivery measure that includes burner recovery; it does not mean the tank contains 84 gallons. Actual hot-water delivery varies with incoming water temperature, settings and usage.
WHE asks which fixtures run together and when hot water becomes insufficient. A large tub, repeated showers or simultaneous laundry may call for a different balance of stored water and recovery. The first-hour rating helps with that assessment, but it is not a guarantee of a particular number of showers.
Dimensions and space around the heater
Rheem lists a 60-inch tank height, a 19½-inch diameter and 63¼ inches to the vent connection. The height above the tank matters when fitting the draft hood and connecting the vent.
The top water connections are ¾ inch on 8-inch centers. The gas connection is 14 inches above the base, and the side temperature-and-pressure relief connection is 53½ inches high. The drawing shows a ½-inch gas connection. Shipping weight is 135 pounds; this is not the filled operating weight.
We also check access through the doorway, room for piping and a drain pan where required, relief-discharge routing, and service access to the gas control, drain valve and anode. Tank dimensions alone are not the minimum dimensions of a suitable installation space.
Propane supply and the correct model number
The LP supply must support this heater’s 36,000 BTU/h input along with the other appliances served. WHE reviews the propane supply, regulator arrangement, pressure, piping capacity and accessible shutoff. The heater’s ½-inch connection does not by itself determine the upstream gas-line size.
The PROG40-40N RH62 natural-gas model has the same rated storage, dimensions, UEF and first-hour rating, but lists 40,000 BTU/h input and 40.4 GPH recovery at a 90°F rise. It is a different fuel version. Rheem’s manual warns against converting the heater to a gas type other than the one on its rating plate.
Also verify the complete suffix when comparing quotes. The PROG40-36P RH AX is a separate version with installed side water connections. This guide covers the RH62 model, whose exact specification row lists 36.3 GPH recovery.
Natural-draft venting and electrical requirements
The US manual identifies this heater as a Category I natural-draft appliance. Rheem’s model row lists a 3- or 4-inch vent. WHE checks the vent size, condition, routing and draft, together with combustion-air provisions and the manufacturer’s required clearances. The listed vent sizes are not permission to reuse an existing vent without reviewing the whole arrangement.
This model uses a pilot and piezo ignition system and has no electrically powered exhaust blower. It does not need the 120-volt blower connection required by a power-vent heater. Any separately powered accessories need their own review. A power-vent or direct-vent installation uses a different arrangement and should be evaluated separately. The manual excludes manufactured/mobile-home use.
Compare other Rheem propane tank options
| Model | Rated storage | Tank height × diameter | First-hour rating | UEF |
|---|---|---|---|---|
| PROG40-36P RH62 | 38 gallons | 60 × 19½ inches | 84 gallons | 0.66 |
| PROG40-32P RH62 | 38 gallons | 58½ × 18½ inches | 67 gallons | 0.59 |
| PROG50-36P RH60 | 48 gallons | 58⅜ × 20½ inches | 85 gallons | 0.64 |
The 32,000 BTU/h 40-gallon version is shorter and narrower, but its first-hour rating is 17 gallons lower than this 36,000 BTU/h model. The 50-gallon RH60 adds 10 gallons of stored water and needs a wider footprint, yet its published first-hour rating is only one gallon higher. These differences show why WHE compares the full model specifications rather than choosing by nominal gallons alone.
If the existing heater has a powered exhaust, the PROG50-42P RH67 PV propane power-vent guide explains that separate option and its electrical and venting requirements. Switching between vent types requires a new installation review.
Maintenance and six-year limited coverage
Rheem lists an anode rod, protective tank lining, sediment-control features and a brass drain valve. The filter-free combustion system does not eliminate maintenance. WHE considers burner and vent condition, sediment, anode access, water pressure, thermal expansion and relief-discharge routing when reviewing installation or service needs.
The standard manufacturer listing is a six-year limited tank and parts warranty, subject to the applicable Residential Warranty Certificate. ProtectionPlus tank-warranty extensions are optional. The tank-and-parts term should not be read as a promise of installation-labor coverage. WHE confirms the applicable equipment terms and any separate installation coverage in the estimate.
Equipment availability and installed price depend on the proposed job and are confirmed after the installation review.
Manufacturer references: Rheem PROG40-36P RH62 product page, US specification sheet, PROG RH N COMBO Rev. 7, May 2024 and US use and care manual, AP22543 Rev. 04. Rheem’s product page retains older series-wide EF wording and some generic series labels; this guide uses the exact Professional Classic propane model row for UEF and delivery. The image is Rheem’s shared atmospheric-series photo; appearance may vary by model.
PROG40-36P RH62 frequently asked questions
Is PROG40-36P RH62 the propane model?
Yes. It is the propane (LP) model with 36,000 BTU/h input. The similarly sized PROG40-40N RH62 uses natural gas. Rheem warns against changing a heater to another gas type.
Does this 40-gallon heater actually hold 40 gallons?
Rheem lists 40 gallons nominal capacity and 38 gallons rated storage. Its 84-gallon first-hour rating is a delivery test result that includes recovery, not the tank’s storage volume.
How tall is it with the draft hood?
The tank is 60 inches tall, and Rheem lists 63¼ inches to the vent connection. The installation also needs the required space for venting, piping, clearances and service access.
Does it need a power outlet or a powered vent?
This atmospheric model uses a pilot and piezo ignition system with natural-draft venting. It has no electric exhaust blower and does not need a 120-volt blower outlet. Separately powered accessories are reviewed individually.
Can I replace any 40-gallon propane heater with this model?
Not solely on the basis of gallon size and fuel. WHE checks the complete model number, dimensions, demand, propane supply, venting and combustion air. Short, power-vent and direct-vent heaters have different requirements.
Request a WHE propane water heater estimate
Text the current model label and photos of the heater, gas connection, vent and surrounding space to 561-602-9062. WHE can review gas water heater replacement options and explain the proposed equipment and installation work. Use the estimate button above to begin your request.