Rheem PROG40S 38NRH62 644196 40 Gal Ng Water Heater

Product Description

The RHEEM PROG40S 38NRH62 644196 is an atmospheric natural gas water heater designed for residential hot water supply systems. Part of the Professional Classic Series, this short-profile unit holds 40 gallons and delivers 38,000 BTU/h of heating output. Its atmospheric vent design uses a standard B-vent flue, making it a straightforward drop-in replacement in conventional installations. Licensed plumbers and HVAC technicians handle installation and service. The compact short-body configuration suits locations with limited vertical clearance while maintaining full 40-gallon storage capacity.

This water heater is rated for natural gas fuel supply and fits residential applications where an atmospheric-style tank water heater is required. The short model designation indicates a reduced-height cabinet, suited for installations in low-clearance utility rooms, crawl spaces with interior access, or alcove installs where a standard-height unit would not fit. It carries a 6-year warranty, consistent with professional-grade residential water heater service life expectations.

Key Features

• 40-gallon storage capacity for residential hot water demand
• 38,000 BTU/h natural gas burner with atmospheric combustion
• Short-profile cabinet at 50.25 inches tall and 21.375 inches diameter for low-clearance installs
• Atmospheric vent design compatible with standard B-vent flue systems
• 6-year warranty coverage on the unit
• Professional Classic Series construction for trade and contractor installation

Compatibility

Designed as an OEM-style replacement or new-installation atmospheric natural gas tank water heater for residential systems requiring a 40-gallon short-profile natural gas unit with B-vent flue configuration.

Installation Notes

Installation must be performed by a licensed plumber or qualified HVAC technician in accordance with local plumbing codes and the International Fuel Gas Code (IFGC). Shut off the gas supply and cold water inlet before beginning any service or replacement work. B-vent flue connections must be properly sized and sealed per manufacturer guidelines and local code. Do not operate the unit before verifying all gas connections are leak-free and the flue path is unobstructed.

Technical Specifications

• Storage Capacity: 40 gallons
• BTU/h Input: 38,000 BTU/h
• Fuel Type: Natural Gas
• Vent Type: Atmospheric (B-vent)
• Unit Height: 50.25 inches
• Unit Diameter: 21.375 inches
• Warranty: 6 years
• Series: Professional Classic Series

Standard Information

• Brand: RHEEM
• Manufacturer Part Number: PROG40S 38NRH62 644196