Age of lochinvar water heater

Find an A. O. Smith replacement water heater. This tool will provide you the best match for your current brand and model. *Product data and claims used to match products and display within this tool are subject to change without notice. Some product dimensions may have changed due to NAECA regulations. Always review manufacture product data and ...

Age of lochinvar water heater. How do you date a Lochinvar water heater? Under the Lochinvar nameplate on the front of the heater. The above models will have either a 7 character or a 12 character serial code. Examples: J-930001… Built in September of 1993 A07H00123456 Built in January of 2007 First letter indicates month produced. Is Lochinvar and AO Smith same?

How to replace a thermopile on a water heater. Since almost all major brands of atmospherically vented water heaters have switched from a thermocouple to a t...

Incoming, cold water mixes the remaining stored water below this 25F° (14C°) limitation. Energy Factor i s an indicator of the combined thermal efficiency and standby efficiency of a water heater. The higher the energy factor, the more efficient the water heater will be. Minerals and gases will separate from water as temperature increases.Rinnai Corporation makes gas water heaters, home heating appliances and accessories to use with them, according to the Rinnai website. You can use the Document Library on the Rinnai website to find a copy of the manual for your product. You...If you have trouble finding a mechanical system installation or service manual, Contact Us and we will research it for you at no charge. Contact Lochinvar Corporation -UK: Lochnivar Ltd. (United Kingdom) 7 Lombard Way The MXL Centre Banbury, Oxon, ON16 4TJ UK General Inquiries: (01295)-269-981 Fax: (01295)-271-640. Previous replacement, improper installation and other conditions, outside the manufacturer’s control and requirements for warranty may prevent reimbursement. A.O. Smith reserves the right to deny reimbursement if, upon investigation, any such condition is identified.The water heater is equipped with 3/4 inch NPT water temperature - pressure relief valve by the manufacturer. connections. Page 13: Gas Piping serving the water heater, and • A drip leg (sediment trap) ahead of the gas control valve to help prevent dirt and foreign materials from entering the gas control valve.Lochinvar Brands Energy Saver Golden Knight Knight Lochinvar uses a 20-letter code for the year of manufacture of their water heaters. The first letter of the serial number is the one to use. The letters I, O, Q, R, U and V are excluded. Because the letter code recycles every 20 years “A,” for example, can be 1964, 1984, 2004. About Lochinvar. For nearly 80 years, Lochinvar, an American company, has been a leader of innovation and high-efficiency water heating. Through Lochinvar's pride in leadership and commitment to excellence, the company has continually improved year after year. Today, Lochinvar touts the broadest line of high-efficiency water heating solutions ...

At Lochinvar, we have long recognized the importance of innovation to any product or service. Those who enter into business must also accept the challenge of meeting constantly changing needs. The designer’s guide you are now holding has been designed to make it more convenient for you to select the perfect Lochinvar water heater for your ...How to determine the date of production/manufacture or age of Lochinvar® HVAC and Water Heater Systems. The date of production/manufacture or age of Lochinvar® HVAC equipment can be determined from the serial number located on the data plate. The Serial Numbers shown are utilized with all Lochinvar Brand systems of …Our Junior Electric water heaters come in a variety of capacities, from 2 to 40 gallons. Space-saving dimensions. Adjustable thermostat. NAECA compliant. Durable fused glass lining.The year and week number of manufacture are encoded in the first four digits of the heater's serial number. So your heater serial number (IF that is what you meant by "product number" - if not, look again on the data tag for the individual water heater's serial number) of 0320030 would translate to. year: 2003. week: 20.Lochinvar has a 6-year warranty on all water heaters they produce. Some models are longer, but you will always get at least 6 years. For high efficiency tanked …How to determine the date of production/manufacture or age of Lochinvar ® brand Water Heater & Boiler Systems. Water heaters in general have an average estimated useful service life of 10-12 years, though water quality, routine …Solar water heaters could help cut your utility bills. Visit HowStuffWorks to learn about solar water heaters. Advertisement Heating up water accounts for a good chunk of a home's energy use. It's a near-constant need -- we use hot water fo...

Lochinvar uses a 20-letter rolling letter code to age their water heaters. The first letter in the serial number denotes the year the unit was manufactured, and the second letter is the month it was made.How Long Does a Water Heater Last? Gas Water Heater Life Expectancy. Posted on March 15, 2018 by E.R. Services - All Things Plumbing, Hot Water Heaters, Water Heaters. Gas Water Heater Basics. A slight majority of Americans have gas water heaters (53%); approximately 40% have electric water heaters.The remaining 7% have …Excerpt: The sidewall fan/powered vent cap MUST be interlocked with the units control system to start the fan on a call for heat and prove fan operation before the boiler fires. LOCHINVAR CFC-CHX INSTALLATION & OPERATION MANUAL [PDF] Models 402-2702 Lochinvar EFFICIENCY + BOILER USER MANUAL [PDF] all modelsLet’s decode the above rating plate: This is water heater model number 21V50-2, serial number 1291A39968, manufactured in December of 1991, 50 gallons, 36000 BTU’s per hour, and is set to work with natural gas only.About Lochinvar. For nearly 80 years, Lochinvar, an American company, has been a leader of innovation and high-efficiency water heating. Through Lochinvar's pride in leadership and commitment to excellence, the company has continually improved year after year. Today, Lochinvar touts the broadest line of high-efficiency water heating solutions ...

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100057228. 100057228 LOCHINVAR CONTROL BOARD GEN,1,ELEM,ON-OFF. Qty ea. Price: $360.14 / ea. Log In for Availability Add to Cart. compare. 100063315. 100063315 LOCHINVAR 4.5KW 240V - 3.75KW 208V SCREW IN ELEMENT 13-1/2IN LONG OLD# ELE1408 ELE1408K 100142494. Qty ea.To age your Daikin equipment, find the serial number that is printed just below the model number on the data plate. The first two digits are the year the equipment was made, and the second two digits are the month. This is the same as aging Goodman HVAC equipment. In the example below the serial number is 1705282056.HotWaterSolutionsNW.org. It might be difficult to predict how long your water heater will survive – depending on the type and fuel source, its lifespan could be anywhere from 8 and 20 years.The typical traditional electric water heater has a lifespan of 10–15 years and is covered by a normal six-year guarantee.If you are unsure of the age of your …The date of production/manufacture or age of Knight/Lochinvar brand Water Heater & Boiler equipment can be determined from the serial number located on the rating data plate. The multiple Serial Number styles shown were utilized with all Lochinvar Brand systems of Boilers, Water Heaters, Pool Heaters, etc. - but typically with specific model …Oct 3, 2023 · Signs That Your Lochinvar Water Heater Might Be Aging. Typically, water heaters require replacement every 10 years, though some might not even last that long. Anecdotal evidence from home inspections revealed the discovery of rare gems – water heaters from the late 1970s still in operation.

Lochinwar water heaters are highly valued by the quality standards for water heater manufacturing (visit : http://waterheaterreviewsno1.com/ ). Lochinwar has...Tank water heaters typically hold 40, 50, or 55 gallons or more. The size you buy depends on the number of people living in your home and your peak water usage.Water heaters in general have an average estimated useful service life of 10-12 years, though water quality, routine upkeep/maintenance, and location of the water heater will all play critical roles in the longevity of these systems. Parent Company: Lochinvar - A subsidiary of A.O. Smith (since 2011)We are a leading producer of energy-efficient water heating solutions that are radically simple, brilliantly engineered and perfectly suited for most any application. We focus solely on serving the unique needs of each customer with a product portfolio including boilers, water heaters, pool heaters, cogeneration products and commercial package ...Tips to estimate the age without a serial number. Brand Histories. Brand info that may help determine an age or era. Select one of the drop-down lists below. that corresponds to the 1st letter. of your HVAC brand name. Then make your selection from the Brand Names list. HVAC - A.About Lochinvar. For nearly 80 years, Lochinvar, an American company, has been a leader of innovation and high-efficiency water heating. Through Lochinvar's pride in leadership and commitment to excellence, the company has continually improved year after year. Today, Lochinvar touts the broadest line of high-efficiency water heating solutions ...Goodman® HVAC age. How to determine the date of production/manufacture or age of Goodman® brand HVAC Systems. The industry average service design life for most forced air furnaces is 15-20 years, and the industry average service design life for most air conditioning condensing units is 10-15 years. The average …The date of production/manufacture or age of Knight/Lochinvar brand Water Heater & Boiler equipment can be determined from the serial number located on the rating data plate. The multiple Serial Number styles shown were utilized with all Lochinvar Brand systems of Boilers, Water Heaters, Pool Heaters, etc. - but typically with specific model …Apr 7, 2023 · It’s just very, very rare. Lochinvar Water Heater Age Chart Locate the serial number on your Lochinvar water heater and check the first letter. Match the letter to the chart below and you will decode your water heater’s age by the year of manufacturing. Let’s check out a real Lochinvar Water Heater label below. The specific items covered under the warranty for a Whirlpool water heater varies from model to model. The actual terms of the warranty can be found in the product’s Warranty Guide.The date of production/manufacture or age of Knight (Lochinvar) brand Water Heater & Boiler equipment can be determined from the serial number located on the rating data plate. The multiple Serial Number styles shown were utilized with all Lochinvar Brand systems of Boilers, Water Heaters, Pool Heaters, etc. - but typically with specific model ...

This category contains Lochinvar Shield and Lochinvar Armor commercial gas water heaters, both available in a variety of models to meet your water heating needs. Free shipping on orders over $99 Your Zip: 23917

Water heaters raise the temperature of water for use in bathing, cooking, irrigation, industry and other hot-water applications. Here’s how the three basic types of water heaters work.How to replace a thermopile on a water heater. Since almost all major brands of atmospherically vented water heaters have switched from a thermocouple to a t...Patterson-Kelley Will Be Attending The 2023 AHR Expo! Read More. Contact Patterson-Kelley. Patterson-Kelley manufactures and sells a full-line of high-efficiency commercial boilers and water heaters for commercial applications.Apr 7, 2023Lochinvar is well-known as a leading manufacturer of high-efficiency hot water heaters, boilers, and pool & spa products, including models incorporating solar technology. With up to 99 percent fuel efficiency in many models, Lochinvar makes an excellent choice for property owners focused on lowering their energy bills and recouping ROI quickly.There are some parts that tend to go bad on hot water heaters, including heating elements on electric water heaters and fuel valves on gas water heaters. Plumbing supply stores that have a local brick-and-mortar presence are a reliable sour...How Long Does a Water Heater Last? Gas Water Heater Life Expectancy. Posted on March 15, 2018 by E.R. Services - All Things Plumbing, Hot Water Heaters, Water Heaters. Gas Water Heater Basics. A slight majority of Americans have gas water heaters (53%); approximately 40% have electric water heaters.The remaining 7% have …Last Udated: October 3, 2023 Lochinvar, a luminary in the water heating industry, has been at the forefront of manufacturing top-notch water heaters. For homeowners and professionals, understanding the age of a water heater is crucial for gauging its efficiency, planning maintenance schedules, and predicting its operational lifespan.The date of production/manufacture or age of Lochinvar® HVAC equipment can be determined from the serial number located on the data plate. Parent Company: Lochinvar. Example serial number styles/formats found: The Serial Numbers shown are utilized with all Lochinvar Brand systems of Boilers, Water Heaters, Pool Heaters, etc.

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At Lochinvar, we have long recognized the importance of innovation to any product or service. Those who enter into business must also accept the challenge of meeting constantly changing needs. The designer’s guide you are now holding has been designed to make it more convenient for you to select the perfect Lochinvar water heater for your ...Jul 19, 2011 · Beginning in 1973, Lochinvar started using a letter year followed by a letter month, excluding certain letters. Letter years: A - 1973 B - 1974 C - 1975 D - 1976 E - 1977 F - 1978 G - 1979 H - 1980 J - 1981 K - 1982 L - 1983 M - 1984 N - 1985 P - 1986 S - 1987 T - 1988 W - 1989 X - 1990 Y - 1991 Z - 1992 A - 1993 B - 1994. Letter months: A ... Sep 3, 2023 · The date of production/manufacture or age of Cadet (Lochinvar) brand Water Heater & Boiler equipment can be determined from the serial number located on the rating data plate. The multiple Serial Number styles shown were utilized with all Lochinvar Brand systems of Boilers, Water Heaters, Pool Heaters, etc. - but typically with specific model ... Temperature range on residential gas water heater is from 110°F ±10° to 155°F ±10° and a 70°F vacation setting. The T&P valve will open at 195°F ± 10°. The water heater temperature adjusting dial is factory set at the lowest temperature, all the way counter-clockwise to the mechanical stop, unless specified differently by provincial or The data plate on your GE water heater should be located along the top of the tank. If your water heater is less than 20 years old, a manufacturing date will likely be printed on this label along with the model and serial number. The manufacturing date should look something like this MFG. Date: 04/2008.It’s designed for good results, and can hold a lot of liquid and water. And it costs a lot. A lochinvar water heater lasts about 5 years before it starts to make a …Lochinvar’s engineers have created some of the industry’s biggest breakthroughs. Building the best water heating solutions has been our mission since day one. Today, our Research & Development department, which is the largest in North America, relentlessly pursues innovations that yield higher efficiency and new ways to make your job even ... Brand Histories. Brand info that may help determine an age or era. WH Brands - A. WH Brands - B. WH Brands - C. WH Brands - D. WH Brands - E. WH Brands - F. WH Brands - G.3. Decode the label by finding out (chart below) how that brand of water heater documents the manufacturing date within the serial number on the label. Water heater manufacturers document the month and year or year and week of manufacturing as part of the serial numbers on the water heater. Check this chart to find the brand water heater you ...Lochinvar is well-known as a leading manufacturer of high-efficiency hot water heaters, boilers, and pool & spa products, including models incorporating solar technology. With up to 99 percent fuel efficiency in many models, Lochinvar makes an excellent choice for property owners focused on lowering their energy bills and recouping ROI quickly.o. The water heater has not been fired at the factory rated input and fuel for which it was factory built; or p. The water heater or any of its component parts fail due to sediment build-up; or q. The water heater does not have installed a temperature and pressure relief valve, certified to ANSI Z21.22 and ….

This Lochinvar water heater makes it to our list as a runner-up because of its high-quality construction. It has a high water storage capacity, decreasing the need for recirculation. This also helps you have a consistent supply of hot water once it gets full. The storage capacity of 75 to 100 gallons is also quite impressive.In example one, they’ve referenced the year as the initial two digits. The next two figures relate to the week number. In example two, we see a system consisting of the letters ‘A’ to ‘M’, excluding ‘I’, to represent the month. The third and fourth numbers indicate the year. Figure 5: American Water Heater.Lochinvar GTN05040 Energy Saver Tall Natural Gas Water Heater, 50 GAL, 40000 BTU/HR. Can't find a product? Call now! 888-756-4110 Cart (0) Items Can't ... Energy Saver Residential Tall Gas Water Heater, Capacity: 50 GAL, Natural Gas Fuel, 40000 BTU/HR BTU Rating, Material: Glass-Lined Steel Tank, First Hour Recovery: 88 GAL, Recovery: ...Lochinvar Brands Energy Saver Golden Knight Knight Lochinvar uses a 20-letter code for the year of manufacture of their water heaters. The first letter of the serial number is the one to use. The letters I, O, Q, R, U and V are excluded. Because the letter code recycles every 20 years “A,” for example, can be 1964, 1984, 2004.Whether replacing an old water heater or putting the water heater in a new location, the following critical points must be observed: 1. Select a location indoors as close as practical or centralized to the water piping system as possible. The water heater should be located in an area not subject to freezing temperatures. 2. The Squire uses the power and efficiency of the boiler that heats the home to generate domestic hot water for showers, dishwashing, clothes washing, etc. 17 Models : Capacities from 30 - 119 Gallons. 316L Stainless Steel Coil and Tank. Fully Welded Construction. Dent Resistant Jacket.LOCHINVAR KNIGHT HEATING BOILER SERVICE MANUAL [PDF] (2010) Models 80-285, Starting Serial #H07H10040039; Lochinvar Knight HEATING BOILER MANUAL [PDF] Models 80-500 ; LOCHINVAR NOBLE FIRE-TUBE COMBI BOILER PRODUCT DESCRIPTION [PDF] LOCHINVAR RB/RW BOILER & WATER HEATER MANUAL …This category contains Lochinvar Shield and Lochinvar Armor commercial gas water heaters, both available in a variety of models to meet your water heating needs. Free shipping on orders over $99 Your Zip: 23917Water heaters in general have an average estimated useful service life of 10-12 years, though water quality, routine upkeep/maintenance, and location of the water heater will all play critical roles in the longevity of these systems. Parent Company: Lochinvar - A subsidiary of A.O. Smith (since 2011) Age of lochinvar water heater, For instance, in serial number 9010-2008–114-1014, the water heater was made on the 14th day of January in 2008. This guide should help you determine the age of your water heater based on its brand and serial number. Always remember to consult with a professional if you have any doubts or concerns about the condition of your water heater., Lochinvar is well-known as a leading manufacturer of high-efficiency hot water heaters, boilers, and pool & spa products, including models incorporating solar technology. With up to 99 percent fuel efficiency in many models, Lochinvar makes an excellent choice for property owners focused on lowering their energy bills and recouping ROI quickly., This natural gas water heater comes with a 3-inch water vet with an overall rating of 95% AFUE. According to the manufacturer, this product can deliver 4.8 gallons of heated water per minute. Additionally, it comes with a 10:1 turndown ratio making its heating capacity just ideal for residential use., Aug 21, 2023 · How to determine the date of production/manufacture or age of A.O. Smith ® brand Water Heater Systems. Water heaters in general have an average estimated useful service life of 10-12 years, though water quality, routine upkeep/maintenance, and location of the water heater will all play critical roles in the longevity of these systems. , Mar 1, 2012 · The third and fourth numbers represent the year. For example *D04 means your water heater was installed in April of 2004. Check to see if the manufacturer is Bradford-White or Lochinvar. Observe the first two letters to determine the year, as part of a 20-year cycle, that the water heater was installed. , 11. All residential tank-type water heater parts have a six (6) year warranty from the date of purchase. 12. All commercial boiler, water heater and pool heater parts have a one (1) year warranty from date of purchase. All residential boiler parts have a two (2) year warranty from date of purchase. 13. , Apr 1, 2019 · Energy saver indirect water heater. Squire indirect water heater. Lochinvar’s 30-50 series is an advanced series of gas hot water heaters, offering you value and an impressive list of features: High first-hour recovery rates. Energy efficiency of 96%. Advanced electronics with large-screen display anddiagnostics. , Water heater stands are typically sold at hardware stores and plumbing suppliers, as well as by the major water heater manufacturers. They typically cost between $40.00 and $150.00 each. Be sure to measure your water heater and check the specs of the water heater stand prior to purchase., LIMITED RESIDENTIAL WATER HEATER WARRANTY ... and component parts for leak age or other mal func tion caused by defects in materials and/or work man ship. It ex tends to the first owner as long as the water heater ... Lochinvar, LLC. • 300 Maddox Simpson Pkwy • Lebanon, TN 37090 • 615-889-8900 / Fax: ..., Lochinvar uses a 20-letter rolling letter code to age his water heaters. The first letter in the serial number denotes the year the unit is manufactured, and the second letter your the month it was made. Skip to content 502-938-5190. Home; Ben's Blog. How To Age ..., The date of production/manufacture or age of STANDARD® Water Heater(s) can be determined from the serial number. Serial number styles/formats found are: Style 1: 043812019. Style 1: 0438 12019. Every effort is undertaken to offer you correct and concise information to assist you in determining the age or manufacture date of water heating ..., Lebanon, Tenn. – Lochinvar, LLC, a leading manufacturer of high-efficiency water heaters, boilers, pool heaters and storage tanks, today announced the upcoming expansion of its world headquarters in Lebanon, Tenn. The project will add 74,000 square feet of manufacturing and storage capacity, as well as an extended office area and a …, Lochinvar Water Heater Age. Here we have mentioned some of the most famous manufacturers and many popular brands, although it is impossible to list every single one. However, just about every company uses a similar system, and all you need to know is how to read the serial number., Water heater age decoders, water heater manual sources, all brands: In addition to details of how to de-code water heater age for all water heater brands we give six ways to determine the age of a water heater. We also discuss the conditions, maintenance, and factors that affect how long a water heater can be expected to last., I just got this info from Lochinvar. Thought some of you might find it useful. I asked for the key to their code for dating Water heaters with Model number or serial number. Here’s what they sent: "The following is a list of the starting letter of the serial number, as it applies to the year of manufacture." G=1990 H=1991 J=1992 K=1993 L=1994., The first two numbers (after a single letter) of the serial number are the year of manufacture of Reliance water heaters. So the water heater with the data plate shown below is from 1995. To determine the age of another manufacturer/brand of water heater, go to How do I determine the age of my water heater?, GSW Water Heating. JohnWood, GSW, Moffat, Superflue, Medal. Serial# – 1 st 4 digits. 1 st & 2 nd number = year, 3 rd & 4 th number = month. 8901xxx= made in the year 1989 in the first month, January. Heat Transfer Products. HeatTransfer. Lochinvar. EnergySaver, Golden Knight, Knight. Marathon. Marathon. Serial# – 1 st 4 digits. 1 st & 2 nd ..., Leaks: If your water heater is leaking, it must be replaced immediately. Leaks are usually the result of pressure buildup inside the tank. This happens when the water pressure or temperature is too high, or when the unit’s relief valve is not working properly. Neglecting a leak can lead to a tank explosion. Signs of leaks include moisture or ..., Jul 28, 2017 · The date of production/manufacture or age of Lochinvar® HVAC equipment can be determined from the serial number located on the data plate. Parent Company: Lochinvar. Example serial number styles/formats found: The Serial Numbers shown are utilized with all Lochinvar Brand systems of Boilers, Water Heaters, Pool Heaters, etc. , AllThingsHVAC Last updated: April 1, 2019 One element of your home's comfort that you may take for granted is a basic need - hot water. Your family becomes accustomed to turning on the faucet and having a plentiful supply of hot water for: Running your dishwasher Taking a relaxing bath Freshening up in a hot shower, Lochinvar has a 6-year warranty on all water heaters they produce. Some models are longer, but you will always get at least 6 years. For high efficiency tanked …, SNR201-100 Shield Water Heater Parts WHN155 Knight Boiler Parts Whether you’re heating water for a corporate building full of people or the daily comings and goings of a small mom and pop shop, Parts Town can keep the water hot and the lights on with our large selection of real OEM Lochinvar parts., To make it simple for Lochinvar themself and us, they created some alphabetic code that can help us determine how old the thing is. For example, say that the serial number is AJ8123596 and A is the year 1964. The thing was made back in 1964. The code also recycles. As the alphabet progress, so does the year. If A is 1964, then B would be 1965 ..., Energy saver indirect water heater. Squire indirect water heater. Lochinvar’s 30-50 series is an advanced series of gas hot water heaters, offering you value and an impressive list of features: High first …, If you’re considering an upgrade to your home’s hot water system, you may be wondering whether switching to a tankless water heater is worth it. While there are some definite advantages to going tankless, there are also a few drawbacks that..., The trick is being able to distinguish the age of water heaters with the same date codes manufactured after 1973. ... Lochinvar Corporation Lochinvar Corporation was acquired by A.O. Smith in July of 2011, so most Lochinvar numbers in …, Lochinvar Water Heater Age Chart. Locate the serial number on your Lochinvar water heater and look for the letter “A” in the beginning. Match the letter to the year on the table below, and you will be able to determine the age of your water heater based on the year it was manufactured. A = 1984, 2004. B = 1985, 2005., About Lochinvar. For nearly 80 years, Lochinvar, an American company, has been a leader of innovation and high-efficiency water heating. Through Lochinvar's pride in leadership and commitment to excellence, the company has continually improved year after year. Today, Lochinvar touts the broadest line of high-efficiency water heating solutions ... , Lochinvar Water Heater Age Chart. Locate the serial number on your Lochinvar water heater and look for the letter “A” in the beginning. Match the letter to the year on the table below, and you will be able to determine the age of your water heater based on the year it was manufactured. A = 1984, 2004. B = 1985, 2005., The lifespan of most water heaters is around 10-15 years, so a 15 year old water heater has exceeded its expected useful lifespan. As water heaters age, they become increasingly less efficient and can start to wear out, displaying signs of deterioration such as rust, corrosion, and strange odors and noises. , This is your single-source solution for who to contact and where to buy any of our products. Distributor. United States. 20 miles. Select an option. Select an option. *Please complete the required fields to continue. We are a leading producer of energy-efficient water heating solutions that are radically simple, brilliantly engineered and ..., Rinnai is one of the most trusted brands when it comes to gas appliances, especially water heaters. However, like any other appliance, it can break down and will need professional attention., Lochinvar Brands Energy Saver Golden Knight Knight Lochinvar uses a 20-letter code for the year of manufacture of their water heaters. The first letter of the serial number is the one to use. The letters I, O, Q, R, U and V are excluded. Because the letter code recycles every 20 years “A,” for example, can be 1964, 1984, 2004.