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AO Smit® - ProMax® SL 40 gal. Gas Water Heater

Item: WH-GCR-40T
MFR: GCR4000L010000
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Product Info


The Promax® 300/301 Series gas water heater is designed to deliver an economical performance that can lower your energy bills and also provide long-lasting value.

Featuring a 40-gallon tank and a 40,000 BTU gas burner, the GCR-40L Standard Vent delivers a first hour rating of 70 gallons and a recovery rate of 41 gallons per hour. With an 0.62 Energy Factor, this water heater is not ENERGY STAR® qualified. It carries a 6-year limited tank warranty, and meets Low NOx emission requirements.

Intelligent Control Logic
The internal microprocessor provides enhanced operating parameters and tighter differentials for precise sensing and faster heating response to optimize performance.
Uses a thermopile to generate the power needed to operate the electronic gas control without requiring an external power source.
The electronic gas control incorporates an LED status indicator that monitors system operation and service diagnostics.
Green Choice® Gas Burner
Patented eco-friendly design reduces NOx emissions by up to 33% and complies with low emissions of less than 40 ng/J.
DynaClean™ Diffuser Dip Tube
Helps reduce lime and sediment buildup, maximizes hot water output. Made from long lasting PEX cross-linked polymer.
CoreGard™ Anode Rod
Our anode rods have a stainless steel core that extends the life of the anode rod allowing superior tank protection far longer than standard anode rods.

How it Works
Gas water heaters heat water by burning either natural gas or LP (propane). Gas water heaters need a source of air and also need to be vented properly. Cold water enters the water heater through an internal "dip tube" which forces the cold water to the bottom of the tank and pushes hot water out through the outlet connection. This arrangement provides the most hot water for a given tank size. Most gas water heaters use a pilot light. The pilot light on some models also generates the power needed to operate an electronic gas valve. When cold water enters the tank, the temperature sensor on the gas control tells the main gas valve to open. Gas flows to the burner where it is lit by the pilot light. The air needed by the burner is supplied by the room where the water heater is installed. The exhaust gases are vented to the outside. When the proper temperature is reached, the main gas valve shuts off. Because water can corrode the steel tank, we glass line the inside of the tank and install an anode rod to help reduce corrosion. The temperature and pressure relief valve is a safety device designed to open if the internal temperature or pressure of the tank exceeds certain limits. Water heaters should be large enough to provide adequate hot water even when temperatures are cold and household demand is greatest.


Weight150 Pound (lb.)
Width21.13 Inches (in)
Height62.31 Inches (in)
Country of OriginMEX
UPC or Barcode671657197681
Hazardous MaterialNo
EPA Cert RequiredNo
Length24.13 Inches (in)
BrandAO Smith
BTU Input40000
Capacity Gallons40
CertificationsANSI Z21.10.1-CSA 4.1
Connection Size3/4"
Energy Star RatedNo
Fuel TypeNatural Gas
Gas Connection1/2"
Gas TypeNatural
Ignition TypePiezo Ignitor
Maximum Pressure (PSI)150 PSI
Maximum Temperature160°F (71.1°C)
UL ListedNo
UL RecognizedNo
Warranty Offered6 Year Parts - 6 Year Tank

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