Lochinvar Gas Water Heaters

Lochinvar gas water heaterLochinvar
(photo: amazon)

Check out Lochinvar gas water heaters for efficient water heating, comfortable showers, and savings. A review of the models, types, and features.

Buying and installing a Lochinvar gas water heater can make a big difference in your home, especially if buying one of the latest and most innovative models. No matter the size, gas models can, in general, heat the water fast and easy, keeping up with the high demand for hot water than the electric one. The operating costs are lower, making them more affordable.

Lochinvar gas water heaters are available as the standard type for residential and light commercial water heating or manufactured housing:


Many of the above Lochinvar gas water heater models meet or exceed the energy efficiency standards, NAECA and ASHRAE.

Also, they meet the ANSI standards required for residential gas-fired water heaters. This is done by implementing the combustion technology that protects from the accidental ignition of flammable vapors outside the water heater. Shield Combustion System is Lochinvar's patented system that meets the above requirements.

Thanks to the Shield Combustion System, Lochinvar gas water heaters are high-efficient units, providing great benefits to the customers and the environment.

The main components for all Lochinvar gas water heaters with the FVIR technology are the Lock-Shield Flame arrestor plate, made of stainless steel, low NOx burner, and resettable thermal switch to protect the water heater from the heat created by flammable vapors.

Most models are equipped with electronic gas control, which utilizes the microprocessor to provide accurate temperature control, and LED status indicators for diagnostics. Low NOx gas burner provides heating by burning natural or propane gas and emit fewer greenhouse gases than the standard type. Some models have ultra-low NOx burners.

Lochinvar models equipped with the pilot light to light the main burner are using the piezo igniter, while some, more advanced, utilize an electronic spark ignition and hot surface.

Lochinvar water heaters utilize glass lining for protection, which is applied to the inner tank surface, and a magnesium high capacity anode rod is added for protection against corrosive water action. A magnesium anode rod is found in most Lochinvar models, while those with stainless steel construction do not have any.

Additional elements that are added for your convenience are the temperature and pressure relief valve as a safety feature and durable brass drain valve for easy fill and drain.

Lochinvar gas water heaters are available with warranties of 6, 8, and 10 years.

Energy Saver

The Energy Saver group of gas water heaters is the standard type that uses the atmospheric vent system and mostly standard features, making it the most affordable group, but with the lower energy factor of up to 0.62.

There are two groups of water heaters with tank capacity ranging from 30 to 55 gallons in short and tall configurations and with warranties of 6 and 8 years.

35-50 series

This is the most advanced group of gas water heaters from Lochinvar. There are several models available utilizing 34 and 50-gallon tanks and gas burners with different gas inputs.

Thanks to the high gas input of 199,000 BTU, the most powerful unit can achieve high first hour ratings of up to 253 GPH, recovery rate of 293 GPH, and energy efficiency of 96%.

The units are equipped with ultra-low NOx gas burners, resulting in less pollution and compliance with the strict emission law, as found in some states.

Models are equipped with advanced electronics, which allows easy control (large screen) and diagnostics.

Features that make them unique and different from most standard gas water heaters are the stainless steel construction of the tank and heat exchangers, which has a helical shape for an enhanced heat transfer. The stainless steel construction eliminates the risk of corrosion, so the anode rod is not needed anymore.

Large capacity

Large Capacity models are recommended for larger homes and applications. They include two tank sizes of 75 and 100 gallons. While they have a high first hour rating of up to 170 gallons and a recovery rate of 81, the energy factor is low – around 0.6.

High efficiency

High-efficiency Lochinvar water heaters are designed in sizes of 40 and 50 gallons in short and tall configurations.

To increase efficiency, all the models utilize atmospheric vents and automatic flue dampers, including a thick foam and heat traps.

The energy factor is higher than the one found on the standard type; it ranges from 0.64 to 0.69. Only the 50-gal unit with the EF of 0.69 is Energy Star compliant, which also has the highest first hour rating of 84 gallons, while the recovery rate is the same for all models – 42 GPH.

Other components are mostly standard, including the low NOx gas burner, electronic ignition, and FVIR technology.

They are certified for potable water and space heating applications. The warranty is 10 years.

Ultra-Low NOx

Thanks to the newly designed radiant burner system, Ultra-Low NOx residential gas water heaters produce less than 10 ng/j of NOx gases. This makes them environment-friendly and compliant with the strict emission laws, as present in some states.

Lochinvar water heaters with ultra-low NOx gas emissions are designed as atmospheric and power vents, in sizes from 30 to 50 gallons, short and tall configurations.

They are equipped with standard features such as the FVIR technology, electronic gas control with the microprocessor, large anode rod, heat traps, etc.

The ultra-low NOx Lochinvar water heater features the Honeywell gas control valve, allowing better and accurate control of the improved economy. It also enables easy diagnostics and troubleshooting with the installed LED display.

The 50-gal unit with the atmospheric venting is the largest model, has 50,000 BTU, energy factor of 0.60, first hour rating of 91 gallons, and recovery rate of 51 GPH. Atmospheric type models are available with 6, 8, and 10-year warranties.

Ultra lox NOx models are also available as power vent models in sizes of 40 and 50 gallons. Due to the high energy factor of 0.70, they are considered as high-efficiency models. The 40-gallon model has the highest efficiency, also the first hour rating of 76 gallons, while the recovery rate is lower than the above model – 43 GPH.

Power vent

Power vented residential gas water heaters are designed in several sizes, from 40 to 75 gallons, and with the power range from 40,000 to 76,000 BTU.

Lochinvar water heaters with the power vent use the environment-friendly low NOx burner, which is part of the standard FVIR technology.

Venting is very simple; power vented water heaters use 120 VAC blower fan and the sidewall flue termination where the pipe is made of the cheaper PVC or CPVC material and can run up to 180 feet. Vertical venting is also an option, and based on the size of the water heater; you will use 2, 3, or 4" vent size.

All the models use standard 3/4" NPT water connection and side connection, so they can also be used for space heating.

The models are equipped with durable and reliable hot surface ignition, control logic to provide an accurate temperature, LED for diagnostics, safety high limit switch, flammable vapor sensor, and protection from the dirt and other contaminants.

The 75-gal model is the largest model, which comes with the highest recovery rate of 80 GPH and gas input of 76,000 BTU but is not Energy Star compliant. The highest first hour rating of 119 gallons is found on the 50-gal unit, with the highest energy factor of 0.73.

All models are certified for both potable water and space heating and come with a 10-year warranty.

Power direct vent

Lochinvar water heaters with the power direct vent utilize the sealed combustion gas burning process to provide a fast recovery and high first-hour rating, and it is available in three tank sizes; 40, 50, and 75 gallons. The maximum gas input is 72,000 BTU, a first hour rating of 129 gallons, and a recovery rate of 82 GPH, all found on the 75-gal unit.

Except for the 75-gal model, all other models are Energy Star compliant due to the energy factor ranging from 0.68 to 0.73.

A power direct venting system is a 2-pipe vent system, where one pipe is used to remove the products of combustion outside and the other for the fresh air intake needed for gas combustion. It can use 2", 3" or 4" PVC, PP, or CPVC vents.

All the models utilize the FVIR technology to prevent accidental ignition, low NOx gas burner for reducing gas emission, electronic ignition and LED for status and diagnostics, and heat traps. Power direct vent water heaters use the hot surface ignition to light the gas inside the combustion chamber.

Models can be used for both domestic water and space heating. The warranty is 10 years.

Balanced flue direct vent

Lochinvar water heater is also available as the direct vent unit that features the sealed combustion and concentric vent system (a pipe within the pipe). The concentric or co-axial vent draws the outside fresh air through the outer pipe and inner pipe; it runs the products of combustion out.

The advantage of these vent systems is in the flexible installation as they can rotate 360 degrees. The vent pipe and vent cap are included with the purchase of the unit.

Available models are with capacities of 40 and 50 gallons and maximum gas input of 47,000 BTU, first hour rating of 83 gallons, and recovery rate of 51 GPH, found on the 50-gal unit. Thanks to the thick foam insulation and installed heat traps, the maximum energy factor found is 0.66 (40-gal unit).

Both models are using a low NOx burner and the pilot light ignition. Except for potable water heating, it can also be used for space heating.

Manufactured homes

Lochinvar water heaters that are specifically designed for manufactured homes can be found with capacities from 30 to 50 gallons for direct vent models and 30 and 40 gallons for the atmospheric type. The maximum gas input of 38,000 BTU is found on the 50-gal DV unit, which also comes with the highest first hour rating of 67 gallons and recovery rate of 67 gallons, while the energy factor is only 0.56. 

All the models come with a low NOx gas burner, FVIR technology, and electronic gas control with the LED status indicator.

A conversion kit is supplied with the unit, so it is convenient to convert the water heater from using natural gas to LP or propane gas, but with a recommendation to call a technician for this job.

A 10-year warranty is offered with the purchase of the models.

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