ASME Packaged Electric Water Heater

What temperature should I set my water heater?

For typical domestic potable hot water service the temperature of your water heater at 125°F is sufficient. This prevents wasted energy (which means cost savings for you) and also decreases the possibility of scalding water burns. If you run out of hot water on this setting, increase the temperature by five degrees incrementally until your hot water needs are met. The goal is to have the temperature set just high enough to meet your needs but within safe operating parameters. Please note that a water heater in and of itself should not be relied upon as the ultimate temperature controlling source for the hot water delivered to your fixtures. Please consult local and state codes for installation of the proper and code approved (ASSE 1016, 1070, 1017) mixing devices to achieve the safe delivery of hot water to the fixtures. For a more complete information please download the whitepaper PDF titled "Understanding Potential Water Heater Scald Hazards" developed by ASSE at the following link ASSE Whitepaper

Which is better for me, a tankless or storage type water heater?

It depends. A tankless water heater is sometimes referred to as a Point-of-Use (POU) or instantaneous water heater. Due to the relative small physical size of a tankless water heater compared to a storage tank water heater, a tankless option can be advantageous from a space saving perspective and can sometimes be installed closer to where you want hot water (hence the term POU). However, tankless heaters are not suited for many applications, so it is critical that before choosing to go tankless you have carefully considered all of the factors that sometimes make the tankless option more complicated and risky compared to a storage type water heater. In particular, you should understand the operational characteristics, maintenance requirements, reparability, and sometimes significant installation requirements of a tankless water heater before making a decision. Tankless units do not store heated water like a storage type water heater; they only heat water as there is demand and therefore must be sized to meet the maximum flow for the application. In some cases a tankless water heater may improve operating efficiency, but possibly at the expense of user comfort. Hubbell tankless water heaters are available inElectric Tankless or Gas Tankless.

How does my water heater ship?

All Hubbell storage type water heaters ship via common carrier and are classified by the Commodity Classification Standards Board under National Motor Freight Classification (NMFC) class 100. Each water heater is palletized and wood crated. All Hubbell tankless water heaters, when transported using common carrier, ship class 77.5. To provide the lowest transportation cost, in most cases the shipment is made on Hubbell’s account and the freight cost is added to the invoice, commonly referred to as “Pre pay and add”. For very large shipments, the most economical method (LTL or Dedicated Truck) for transporting the water heaters to the final destination will be analyzed by Hubbell's transportation department.

Does the Hubbell electric tankless water heater restrict water flow?

No. Hubbell electric tankless water heaters do not restrict water flow. Other brands may incorporate a flow restrictor device within their tankless heater or require a flow restricting device be installed in the plumbing or fixture itself as a method for controlling temperature. This is not the case for Hubbell electric tankless water heaters.

How small is the Hubbell electric tankless water heater?

About the size of an average briefcase. The Hubbell tankless water heaters are a fraction of the size of a conventional storage tank type water heater and they mount on the wall, so you can reclaim 100% of the floor space once occupied by your conventional water heater.

Can the standard Hubbell tankless water heater be installed outside?

No. However, Hubbell does off an electric tankless model with NEMA 4 construction and is suitable for outdoor installation, please see Hubbell model TX.

What temperature should the tankless heater be set to?

The Hubbell electric tankless water heater can be configured by the user to operate in any of three different ranges. Low temperature range is 32-104°F, Standard range is 32-140°F and High Temperature range is 32-194°F. The operator can field configure the electronic controller to operate in any of these ranges, and can then select a set temperature within the selected range that is appropriate for the application. The controller is also field configurable for either °F or °C operation and visual display

What is the difference between gas & electric tankless water heaters?

The most obvious difference between gas and electric tankless water heaters is the energy source that is used. Gas tankless heaters use either Natural Gas (NG) or Propane (LPG), but also use electricity (120v) to power an internal fan and other controls. Electric tankless heaters operate using only electricity. Electric tankless water heaters operate at higher energy efficiency, in the case of Hubbell the thermal efficiency is 98%+, compared to gas tankless which ranges from Energy Factor ratings of 0.82 to 0.96 depending upon model. Electric tankless is more efficient in large part because gas tankless models operate by burning gas, which is harder to control than electricity and is less efficient due to heat lost in the flue exhaust. Gas heaters require exhaust and/or fresh air intake venting, whereas electric heaters do not. Please note that efficiency and operating cost are two different things, to determine operating cost one must consider their cost of energy and usage in addition to the operating efficiency of the heater. Gas tankless water heaters cost more to purchase compared to electric tankless heaters. When replacing a storage tank type water heater with a tankless heater, it should be noted that both gas and electric tankless require changes to the existing plumbing and wiring of the tank they are replacing. When installing a new gas tankless heater, most installations will require a new/upgraded venting and gas line. When installing a new electric tankless heater, most installations will require upgraded wiring to the heater and replacement of the circuit breakers in the electrical panel. The largest available residential and light duty commercial gas tankless water heater is 199,000 BTU/Hr, but the most common size has an output of about 123,000 BTU/Hr. After factoring for energy efficiency, this is equivalent to roughly 36 kW. By contrast, the largest residential/light duty commercial electric tankless water heater is 27 kW, which has an effective output of 91,000 BTU/Hr. In terms of operation and maintenance, a gas tankless heater is considerably more complicated to maintain and service compared to electric tankless. In addition, an electric tankless heater will provide more accurate and consistent hot water temperature throughout a full range of flow rates compared to a gas tankless heater. However, gas tankless heaters because they are available in larger BTU sizes can provide a higher hot water flow rate/temperature rise for very large installations compared to a standard electric tankless heater.

Can my tankless heater serve a fixture that has an anti-scald valve?

Yes. However, it should be noted that a tankless water heating system is generally set to a “just right” temperature, unlike traditional storage tank water heaters which generally overheat the water and require mixing down to achieve a “just right” temperature. Therefore, with a tankless heater you may have to adjust the anti scalding valve to the maximum setting due to the delivery of “just right” temperature water to the shower valve.

What is the life expectancy of the Hubbell tankless water heater?

Depending on the type of installation, usage and water quality, the Hubbell electric tankless water heater can last from 15 to 25 years. In a typical application when properly maintained a Hubbell electric tankless water heater should have no problem lasting 25 years or more.

Will I get instant hot water with a tankless water heater?

This is a common misconception of tankless water heaters. A tankless water heater does heat water on-demand instantly. Just like a tank water heater, it still takes the same amount of time for the hot water to travel through the pipes and flush out the standing water that has cooled down and is already inside the hot water plumbing. No matter what type of heater is installed, it will always take time for the hot water to travel through the plumbing before arriving at the fixture. The length of time it takes always depends on the length of the pipes, the amount of flow through the fixture and the water pressure. In general, a centralized water heater will require the most time to deliver hot water to the fixture, whereas a Point-of-Use water heater will deliver hot water to the fixture in the shortest amount of time.

Is Tankless right for my application?

It depends. Due to the relative small physical size of a tankless water heater compared to a storage tank water heater, a tankless option can be advantageous from a space and weight saving perspective and can sometimes be installed closer to where you want hot water. Tankless water heaters do not store heated water like a storage type water heater; they only heat water as there is demand and therefore must be sized to meet the maximum flow and temperature rise for the application. Therefore, before proceeding with a tankless heater you must carefully understand your application and review your available power. Hubbell offers a wide range of electric tankless marine heaters go to Electric Tankless for details. It is critical that before choosing to go tankless you have carefully considered all of the factors that sometimes make the tankless option more complicated and risky compared to a storage type water heater.

Which NSF Standard is appropriate for this product?

The appropriate NSF Standard to use is NSF 5, titled “Water Heaters, Hot Water Supply Boilers, and Heat Recovery Equipment”. In the past the lead content requirement was only required in NSF 61 per Appendix G, but within the past few years changes have been made such that Appendix G has been removed and replaced by NSF 372, “Drinking Water System Components – Lead Content”. NSF 5 requires materials approved by NSF 51, “Food Equipment Materials” and the latest edition of NSF 51 requires that the materials comply with NSF 372. Therefore, NSF 5 now complies with the same low lead requirements as NSF 61.

Can my heater ship via UPS?

Yes. Hubbell packages and ships this model water heater via United Parcel Service (UPS).

How is a tankless heater different from a storage tank heater?

A storage tank water heater maintains a tank full of hot water 24/7/365 and will heat water even during periods of no usage in order to make up for standby heat loss. A tankless water heater only consumes power (whether its gas or electric) when there is demand for hot water. They take up significantly less space and typically can be located close to the point of use, thus providing more efficient delivery of hot water. Tankless water heaters provide continuous hot water and never run out as long as the heater capacity is not exceeded.

Is 277 volt 3 phase voltage available for a water heater?

For all water heaters 277V is only an available option in 1PH, not 3PH. The 277V 1PH voltage is a derivation of your existing 480V 3Ph power. Where 480V is the line to line voltage on a 3 phase system and 277V is the voltage from any one of these lines to neutral, thus making the 277V power available in 1PH only.

Does Hubbell offer DNV certification?

Yes. Hubbell marine water heaters come standard with ABS Type Approval, but and are also available on request with other third party approvals including DNV, BV or NR-13.

Do Hubbell water heaters qualify as Low Lead?

Yes, all Hubbell water heater models qualify as meeting the low lead requirements of the “Reduction of Lead in Drinking Water Act” amendment to the “Safe Drinking Water Act” (SDWA) Section 1417(d) effective as of January 4, 2014. Hubbell certifies that its water heaters meet the following requirements of the SDWA and therefore are qualified and certified as Low Lead : (a)Hubbell water heater do not contain more than 0.2 percent lead with respect to solder and flux (b)Hubbell water heaters do not contain more than a weighted average of 0.25 percent lead with respect to all wetted surfaces of the water heater

What is the difference between solid-state and electromechanical relays?

Depending on the application, one switch may be more advantageous than the other. Please refer to this article to read more about the differences between solid-state and electromechanical relays.

Does my tankless water heater need a T&P relief valve?

Yes and no. NEC paragraph 422-27 requires all water heaters to be equipped with a temperature limiting device in addition to its control thermostat with the exception of instantaneous water heaters identified as being suitable for such use and with a capacity of 4L (1 gallon) or less. Hubbell tankless heaters are have a capacity of less than 1 gallon and are listed to UL Standard 499 which is recognized by NEC and thus meet the requirements of this exception. However individual state and/or local plumbing codes, such as Massachusetts and Kentucky, may require the installation of a temperature and pressure (T&P) relief valve. Therefore Hubbell recommends checking state and local plumbing codes for verification.

Is American Bureau of Shipping (ABS) approval needed?

Equipment and specifically water heaters for use in commercial marine applications require special construction features to ensure longevity and proper operation in a marine environment. In addition, the water heater must be constructed in conformance to the Code of Federal Regulations USCG 46 CFR Part 53.01 and the pressure vessel must be designed and constructed to the proper ASME code and stamped. A Hubbell marine water heater is manufactured under a Certificate of Manufacturing Assessment as issued by American Bureau of Shipping (ABS) Here

Are any Federal, State, local or utility incentives available?

Depending upon your location and the type of water heater you select for your application, there may be financial incentives offered by local, state or federal government and/or your local utility. By visiting the following website at Incentives and clicking on your state, you may find available rebates and incentives.

How does the heat trap work?

The Hubbell water heater is constructed with a heat trap installed within the water heater’s hot water outlet connection. This device helps prevent heat from escaping through the storage tank’s hot water outlet during standby periods, resulting in improved operating efficiency. The heat trap is constructed from a specially designed bronze nipple with an internal floating ball that during standby periods of no flow settles and closes off the storage tank thereby preventing thermal conduction of hot water radiating through the hot water outlet.

Can a timer be installed on my Hubbell water heater?

Water heater timers are devices that provide automatic control of electric water heaters. They can be programmed to turn a water heater off or on at times typically set by your local utility. Your local electric utility may have in place an “Off-Peak” or Time-of-Use (TOU) rates which offer a customer the incentive to consume power during certain periods of the day. The Hubbell Model E is available with various timer control options, ranging from programmable 7 day timers to utility specific devices that control the water heater.

What temperature should I set my water heater?

For typical domestic potable hot water service the temperature of your water heater at 125°F is sufficient. This prevents wasted energy (which means cost savings for you) and also decreases the possibility of scalding water burns. If you run out of hot water on this setting, increase the temperature by five degrees incrementally until your hot water needs are met. The goal is to have the temperature set just high enough to meet your needs but within safe operating parameters. Please note that a water heater in and of itself should not be relied upon as the ultimate temperature controlling source for the hot water delivered to your fixtures. Please consult local and state codes for installation of the proper and code approved (ASSE 1016, 1070, 1017) mixing devices to achieve the safe delivery of hot water to the fixtures. For a more complete information please download the whitepaper PDF titled "Understanding Potential Water Heater Scald Hazards" developed by ASSE at the following link ASSE Whitepaper

Do I need to install an insulation blanket?

No. Most new electric water heaters are highly efficient with respect to the amount of heat loss radiating from the storage tank. This is due to the use of “blown in” polyurethane foam insulation as the insulating method for modern tanks, compared to the fiberglass blanket style insulation used by water heater manufacturer’s largely in the past. As such there is little to no benefit, and very possibly a detrimental effect to efficiency, installing an insulation blanket on a new electric water heater constructed with foam insulation.

What is the average life of an electric water heater?

The most important factor related to the life expectancy of a water heater is the quality and type of storage tank. On an average the life expectancy of a glass lined electric water heater is about 10-12 years (according to the National Association of Home Builders 2007 Study of Life Expectancy of Home Components http://www.nahb.org/fileUpload_details.aspx?contentID=99359 ), compared to a cement lined electric water heater’s average life expectancy of 23-26 years (Independent study of over 25,000 installations for an Electric Utility). Of course, there are various other factors that affect longevity including pressure fluctuations, usage, water conditions, environmental conditions, etc.

Is it OK to use softened water with my cement lined tank?

Yes it is OK. A water softener system will not affect the longevity or operation of a Hubbell cement lined water heater tank. A water softener is typically installed when a potable water system has hard water resulting in the need to soften the water. Unfortunately, the salt used in a water softener corrodes the anode rod and exposed steel surfaces of the water heater tank, rapidly causing a glass lined water heater to corrode and leak within a few years. This is an issue for a glass lined water heater due to its reliance on a sacrificial anode, however because a cement lined tank does not use a sacrificial anode softened water is of no concern to the Hubbell cement lined tank.

What is a sacrificial anode and does a cement lined tank need one?

All water heaters constructed using a steel tank requires a lining to protect the internal steel surfaces from corrosion. Certain linings (i.e. glass and epoxy), due to their nature, have unavoidable holes and imperfections resulting in exposure of the steel tank. As a result of this deficiency, the manufacturer will install an anode rod(s) in an attempt to delay corrosion of the steel tank. An anode rod is typically made of aluminum, magnesium or zinc, is a maintenance item that requires periodic inspection and replacement, and is often times the cause of a “rotten egg” odor to your hot water. Often referred to as a sacrificial anode rod because, over time, it slowly dissolves, sacrificing itself as it is attacked by aggressive substances in the water which would otherwise attack the steel tank through the pinholes and imperfections of the glass or epoxy lining. A cement lined steel tank on the other hand does not require an anode because of the thickness and guaranteed 100% coverage of the cement lining over all internal surfaces of the steel tank. This eliminates the need for an anode rod in a cement lined water heater, resulting in a significantly longer life compared to a glass or epoxy lined water heater. For a further discussion please click on the following link Cement Lining

What is the max water temperature setting?

The Hubbell cement lined tank is suitable for storing water up to 194°F. However, it should be noted that your water heater will likely require optional control accessories to achieve this temperature, but there is no concern regarding the ability of the lining to withstand this temperature. Additionally, there are numerous safety concerns that must be considered when storing water at elevated temperature, please consult factory.

Why is there an upper and a lower heating element in my tank?

Hubbell Model E water heaters with 30 gallon storage or more have both upper and lower heating elements in the tank, and models 20 gallon storage and less have one heating element in the tank. The purpose of having two heating elements in a tank is to improve the recovery rating in a water heater of significant storage capacity. Sometimes referred to as a “Quick Recovery” water heater, this configuration allows the upper element to heat a much smaller volume of water (about 25% of the tank's capacity) before the lower element takes over. This provides a small amount of usable hot water quickly while you wait for the bulk of the water to heat. It is worth noting that in the standard dual element design, the upper and lower heating elements are interlocked so that only one can heat at any time, with priority to the upper element. Once the thermostat controlling the upper element is satisfied (i.e. at set point temperature) the lower element is allowed to heat. As an option, you may order your Hubbell water heater with the optional “simultaneous operation” feature which allows each element to operate independently, potentially allowing both to be on at the same time in order to increase the recovery rate of the heater.

What is the difference between surface and immersion thermostats?

A surface thermostat is a bi metallic sensing temperature regulating thermostat that senses the outer wall temperature of the water heater tank. An immersion thermostat is a bulb and capillary style temperature regulating thermostat that senses the water temperature through a dry immersion well in the water. A surface thermostat is adjustable up to a maximum of 170oF and an immersion thermostat adjusts up to a maximum of 194oF. A surface thermostat is typically used in low wattage water heaters, whereas an immersion thermostat is used in high wattage water heaters.

Which is better for me, a tankless or storage type water heater?

It depends. A tankless water heater is sometimes referred to as a Point-of-Use (POU) or instantaneous water heater. Due to the relative small physical size of a tankless water heater compared to a storage tank water heater, a tankless option can be advantageous from a space saving perspective and can sometimes be installed closer to where you want hot water (hence the term POU). However, tankless heaters are not suited for many applications, so it is critical that before choosing to go tankless you have carefully considered all of the factors that sometimes make the tankless option more complicated and risky compared to a storage type water heater. In particular, you should understand the operational characteristics, maintenance requirements, reparability, and sometimes significant installation requirements of a tankless water heater before making a decision. Tankless units do not store heated water like a storage type water heater; they only heat water as there is demand and therefore must be sized to meet the maximum flow for the application. In some cases a tankless water heater may improve operating efficiency, but possibly at the expense of user comfort. Hubbell tankless water heaters are available inElectric Tankless or Gas Tankless.

What is the water pressure drop through the tank?

There is no major restriction of water flow through the Hubbell water heater. Cold water inlet and hot water outlet sizes are available in ¾” and 1-1/2” sizes to accommodate your application. By far, the ¾” size is more than adequate for most applications using a model E water heater. If your flow rate through the water heater is greater than approximately 10 GPM you may want to consider the 1-1/2” connection option (must be specified at time of ordering). As an approximate, pressure drop through any E model water heater with ¾” connections will be <4 psi with a flow rate of <10 GPM, and with 1-1/2” connections the pressure drop will be <3 psi with a flow rate of <20 GPM.

Why is the T&P valve tested to ASME standards (as opposed to CSA)?

The Hubbell water heater is built to and approved by UL to ANSI/UL 174 and CAN/CSA-C22.2 No. 110 (1990). These standards require that each assembled water heater be shipped with a factory installed combination temperature and pressure relief valve sized in accordance with ASME requirements. However, if a relief valve sized to CSA is required, you must indicate this at time of requesting a quote for your water heater as this may necessitate a larger opening in the tank to accommodate a larger CSA relief valve. For reference, please see the following link to an article on this subject Here

Do I need a drain pan under my heater?

Yes, Hubbell advises that a drip pan with a proper drainage connection be installed under your water heater. In some locations drip pans are required by code and in other situations they are highly recommended, but not required. In either case, if a water heater leak or a dripping relief valve could result in property damage then a drip pan must be installed under the water heater, even when not required by code.

Is there a cold water dip tube in the Hubbell tank?

Not exactly. The Hubbell cement lined tank includes a cold water diffuser integrated into the cold water connection which allows incoming cold water to be introduced into the tank in a controlled and non turbulent manner, thus avoiding premature mixing of cold water with the hot water in the tank. On Hubbell cement lined tanks the cold water inlet/diffuser is located on the side in the lower portion of the tank. Therefore, a Hubbell cement lined tank does not require a long dip tube extending all the way from the top to the bottom of the tank as is common in glass lined tanks.

How does my water heater ship?

All Hubbell storage type water heaters ship via common carrier and are classified by the Commodity Classification Standards Board under National Motor Freight Classification (NMFC) class 100. Each water heater is palletized and wood crated. All Hubbell tankless water heaters, when transported using common carrier, ship class 77.5. To provide the lowest transportation cost, in most cases the shipment is made on Hubbell’s account and the freight cost is added to the invoice, commonly referred to as “Pre pay and add”. For very large shipments, the most economical method (LTL or Dedicated Truck) for transporting the water heaters to the final destination will be analyzed by Hubbell's transportation department.

What is the Energy Factor (EF) rating?

The Energy Factor (EF) rating represents the efficiency of the water heater. The higher the EF, the more efficient the water heater unit. Hubbell Model E water heaters are classified by the Department of Energy as residential water heaters and are rated by an Energy Factor (EF) ranging from 0.80 to 0.92. The higher the EF, the more the heater transfers energy to the water using less energy. Please note that the use of R values as a measure of efficiency is incomplete and does therefore does not accurately capture a water heater’s true efficiency as does the EF rating. For additional information check out the Air-Conditioning, Heating, and Refrigeration Institute (AHRI) website at AHRI as well as the American Council for an Energy Efficient Economy (ACEEE) website at ACEEE

Why is Hydrastone Cement a better choice over glass lining?

Cement lining provides guaranteed 100% coverage with a minimum thickness of 0.5” over all internal tank surfaces. In comparison, glass lining is approximately 0.005” thick and includes imperfections, pinholes and variation in coverage thickness resulting in portions of unprotected steel tank exposed to corrosion. In an attempt to compensate, glass lined tanks include a sacrificial anode in an effort to slow down the corrosion of the tank. Cement lined tanks on the other hand do not require an anode due to the integrity of the lining. As such, a cement lined tank will far outlast a glass lined tank. For a more complete explanation of the benefits of the Hubbell cement lining please click on the following link Cement Lining

What does 3 phase Open Delta wiring mean to me?

Without getting into a lengthy discourse on electricity, the simple answer is that any water heater internally wired in a 3 phase open delta configuration is unbalanced, meaning that the amperage drawn by one of the three legs is high and unequal to the other two legs. This unbalanced water heater can have a detrimental effect on a buildings power system and therefore needs to be carefully understood before you install a water heater configured for 3 phase open delta. It should be noted that the branch circuit protection (i.e. circuit breaker) servicing a 3 phase open delta water heater needs to be sized for the high amperage leg. The Hubbell model E is available up to a maximum of 12kw in 3 phase open delta wiring. Alternatively, the Hubbell model SE is a balanced 3 phase water heater, meaning that all three legs draw equal amperage. The Model SE is available up to 58kw click here details Model SE

Why is a cement lined tank a better choice than stainless steel tank?

In almost all cases, a cement lined steel tank is a more robust tank compared to stainless steel. The weakness of a stainless steel tank is in the materials susceptibility to SCC (Stress Corrosion Cracking) caused by chlorides, bromides, iodides and fluorides in the water. The combination of residual stresses from welding, roll forming and stamping, and the cyclic stress from operating in a hot water system are sources of tensile stress, that when above a certain threshold stress, will make a stainless steel water heater tank susceptible to stress corrosion cracking. Cement lined steel tanks are not susceptible to this condition, and therefore are more resistant to corrosion and withstand the pressure and temperature cyclical operation of a water heater.

When should I specify an immersion thermostat?

An immersion thermostat should be specified when the desired operating temperature either is below 110F or above 170F, or the water heater is to be used in an unusual application that is outside of the normal operating parameters of a typical domestic water heater. Otherwise, the type of thermostat (surface or immersion) is determined by Hubbell as is appropriate for the kw and storage tank size of the water heater.

Is this model approved by Massachusetts?

Is American Bureau of Shipping (ABS) approval needed?

Equipment and specifically water heaters for use in commercial marine applications require special construction features to ensure longevity and proper operation in a marine environment. In addition, the water heater must be constructed in conformance to the Code of Federal Regulations USCG 46 CFR Part 53.01 and the pressure vessel must be designed and constructed to the proper ASME code and stamped. A Hubbell marine water heater is manufactured under a Certificate of Manufacturing Assessment as issued by American Bureau of Shipping (ABS) Here

Is 277 volt 3 phase voltage available for a water heater?

For all water heaters 277V is only an available option in 1PH, not 3PH. The 277V 1PH voltage is a derivation of your existing 480V 3Ph power. Where 480V is the line to line voltage on a 3 phase system and 277V is the voltage from any one of these lines to neutral, thus making the 277V power available in 1PH only.

What is the R value of a Hubbell water heater?

Hubbell uses a blown-in polyurethane foam insulation for all cement lined water heaters and tanks up to 150 gallon capacity. This insulation has an R value of 7.2 per inch. Most Hubbell tanks have a minimum of 2 inches of insulation resulting in an R value of 14. Certain models are available either standard or as an option with 3 inch insulation and therefore have an R value of 21. Large storage water heater tanks over 150 gallon capacity and custom made stainless steel or alloy tanks have either 2" or 3" fiberglass insulation with an R value of 3.5 per inch.

What type of venting can I use?

The Hubbell gas tankless heater can be vented with PVC, CPVC or Polypropylene. Please see Installation, Operation and Maintenance manual for complete venting details.

Why Hubbell recommends 300 series versus duplex stainless steel?

While it is true that duplex stainless steel typically offers higher strength and resistance to Stress Corrosion Cracking (SCC) and chloride corrosion compared to austenitic (300 series) stainless steel, there are other factors that ultimately make it a less desirable choice compared to 300 series stainless steel. Duplex stainless steel makes up only 1% of the stainless steel market making it less readily available and higher cost especially in flanges, fittings and formed parts such as tank heads. While it is commonly stated that this added expense is offset by the ability to use material that is thinner due to the higher strength, this only applies to very large tanks where a reduction results in using a lower common plate thickness. As an example, a thickness reduction of 25% for a tank that is 3/16" thick in 300 series stainless steel still results in using the common 3/16" thick plate size in duplex stainless steel. The higher strength of duplex also has the negative result of decreased formability and machinability, adding cost to the fabrication and production process. In terms of welding, duplex stainless steel presents many problems in maintaining the proper two phase mixture which commonly leads to issues in the Heat Affected Zone (HAZ) such as loss of corrosion resistance, toughness, and post-weld cracking. This is true in all duplex stainless steel welding processes including TIG, MIG and Laser. By comparison the process of welding austenitic stainless steel is much more forgiving. The main weakness of austenitic stainless steel is its susceptibility to Stress Corrosion Cracking (SCC) and chloride corrosion. Three factors that all must all be present cause this type of corrosion: elevated heat, the presence of chlorides, and residual stresses. In water heaters elevated heat and the presence of chlorides cannot be controlled. However, post-weld heat treating in a vacuum furnace followed by cooling in an inert atmosphere relieves the residual stresses in austenitic stainless steel tanks and therefore eliminates the susceptibility to this corrosion. For this reason, this post-weld heat procedure is performed on all Hubbell stainless steel tanks. The heat treating process is highly controlled and verifiable, unlike the difficult to control process of welding duplex stainless steel. Therefore, Hubbell offers stainless steel tanks fabricated from the 300 series (typically Type 304L or 316L) only, as this is a far more proven and verifiable material and fabrication process which will result in longer tank life. Of course, an alternative option is to specify the Hubbell cement lined steel tank which also provides a considerably longer life and is a more economical solution compared to duplex stainless steel and 300 series stainless steel.

Do Hubbell water heaters qualify as Low Lead?

Yes, all Hubbell water heater models qualify as meeting the low lead requirements of the “Reduction of Lead in Drinking Water Act” amendment to the “Safe Drinking Water Act” (SDWA) Section 1417(d) effective as of January 4, 2014. Hubbell certifies that its water heaters meet the following requirements of the SDWA and therefore are qualified and certified as Low Lead : (a)Hubbell water heater do not contain more than 0.2 percent lead with respect to solder and flux (b)Hubbell water heaters do not contain more than a weighted average of 0.25 percent lead with respect to all wetted surfaces of the water heater

Can my cement lined tank be damaged during installation and handling?

Although we don’t advocate dropping our tanks sometimes stuff happens. The Hubbell Hydrastone cement lining is a minimum of 1/2"thick (100 times thicker than a glass lined tank) and is guaranteed to uniformly cover 100% of all internal tank surfaces. Basically the Hubbell cement lining is a tank within a tank and should have no problem withstanding the rigors of shipping and installation. Although not necessry, you can specify an optional hand hole on our smaller tanks (150 gallon and under) to provide a means for inspection and repair. Water heaters with tanks larger than 36" generally include a 12" x 16" manway. In both cases, a Hubbell tank properly maintained will last decades.

What is the difference between solid-state and electromechanical relays?

Depending on the application, one switch may be more advantageous than the other. Please refer to this article to read more about the differences between solid-state and electromechanical relays.

How do I prepare my water heater for long term storage?

The water heater must be stored in the orientation of intended use (vertical, horizontal). The recommended ambient air temperature range is between 50 and 105 degree F and not exceeding 65% Rh. Under no conditions should the unit be subject to freezing temperatures. The unit is intended to be stored indoors, protected from the elements. Desiccant material should be inserted into the electric control panel and heating element terminal house (if applicable). Prolonged storage will require periodic inspection of desiccant. For cement lined tanks only, place approximately 10 gallons of water in the tank before closing and sealing all openings to ensure a humid atmosphere for the lining is maintained. Cap and seal all openings and tank tappings and/or flanges. Provide the necessary protection to ensure the tank and all accessories are protected from physical contact that could result in damage. Shrink wrapping or other suitable protective plastic may be applied to the exterior. Start up and installation guidelines must be followed, with particular attention to testing of the electric heating element.

When is ASME code required?

Engineers and designers should consider all local codes when specifying approval requirements. For an in depth explanation, reference the National Board of Boiler and Pressure Vessel Inspectors Guide In general, water heater pressure vessels require ASME if the heat input exceeds 200,000 Btu/Hr (58.6kW) or if the storage capacity exceeds 120 gallons. Many water heater manufacturers choose to label and rate their tank 119 gallon to avoid any confusion. However, a tank rated at 120 gallons does not require ASME as code is only required for tanks that exceed 120.