Water is said to be hard when it contains a significant amount of minerals. The most prominent of these minerals are calcium and magnesium.
It does not necessarily take a laboratory test to register the presence of these minerals. It will become quite obvious when you boil a pot of water and it leaves a white residue on the sides and bottom.
This white coating of minerals is called “scale.” It can build up inside the pipes that deliver the water to outlets like sinks or toilets. Scale formation inside plumbing is more rapid when the water is heated.
Electric Water Heater to Buy for Hard Water
Scale problems make it more expensive to heat water. It takes longer for heat to transfer from the source to the water.
Sometimes, the build-up is so bad that it occupies the space that should have been taken up by the hot water. This reduces the capacity of the water tank. When the mineral build-up has gone undetected for long, it will cause the tank to overheat and spoil.
The purpose of this buying guide is to provide you with viable options for heating hard water without negative consequences.
The point of use in this water heater means installing pipes to transport the water is unnecessary. It must be installed close to the hot water outlet, such as a bathtub or dish sink. It is small enough to be fitted into a tight space.
- The tank is made of a thin (heavy gauge) stainless steel material
- The inside of the tank is reinforced with Duraglas that is melded to the steel wall to prevent corrosion
- It has eco-friendly non-CFC foam insulation to increase energy efficiency by minimizing heat loss to the surrounding environment
- Preinstalled brass drainage valve at the bottom of the tank allows the easy evacuation of sediment deposits at the bottom. This prevents build-up, ultimately extending the life of the tank.
- Preinstalled pressure and temperature relief valve at the top of the tank can release water in case the pressure or temperature inside the tank gets too high
- This unit heats water by immersing an anode directly into the water
- It has 150 PSI working pressure and withstands up to 300 PSI
- The measurements of the tank are 18.5 × 18.5 × 24.9 inches
- The tank weighs 73.8 pounds (33.48 kg)
- 6-year limited tank and parts warranty for residential use, while commercial use has a 3-year limited warranty on the tank and 1-year on the parts
What We Like
- The outer material is compact yet strong
- The inner lining is protected from both rust and scale build-up
- It is energy efficient
- Temperature/pressure release valve eliminates the risk of overheating
- It is easy to clean the tank regularly
- The electric tank is compact enough to be installed in tight spaces
- It can be used for both commercial and residential purposes
What We Don’t
- You have to install this tank at the output – adding any length of pipe to transport the water will lose the heat along the way
This electric water tank is better suited for home use rather than commercial use. Nineteen gallons (71.92 L) of water will comfortably meet the hot water needs of small households. On the other hand, it will hardly meet the threshold for commercial use.
It is easy to install too. Here’s to another DIY home improvement project!
The Ecosmart POU 3.5 is a dainty, portable, and energy-efficient water heater. Judging by the size, you can already guess that it is meant for a single-source use one at a time. It will provide your sink with hot water as often as you need it.
- Every bit of technology in the POU is designed to enhance its efficiency
- It has an output of 0.5 gallons (1.89 L)/min of hot water. It has a 0.5 GPM aerator to produce a pressurized stream to conserve water and reduce the amount of electricity used to heat it.
- The Ecosmart 3.5 performs optimally in areas with a water temperature of at least 57℉. Any lower and the heating capabilities of this unit will drop.
- It uses 60% less energy than conventional water heaters
- A flow rate of only 0.25 gallons (0.95 L)/min is enough to activate the heating component
- After activation, a water flow sensor regulates the amount of electrical energy that is used to heat the water by adjusting the flow rate to one that uses the optimum energy.
- Includes a digital display and a temperature controller, both of which are used to monitor and adjust the heat levels
- The temperature can be set from the lowest at 80℉ to the highest 140℉, in increments of 1℉
- A compact design of 11 × 6.5 × 3.5 inches
- It weighs only 3lb (1.36 kg), so it can easily fit right next to the sink
- It requires minimum 100 amps to install and a 30 amp single circuit breaker pole and a number 10 AWG
- NPT requirements are ½-inch plumbing
- 1-year warranty on the element, heat exchanger, and electronic parts
What We Like
- Simple to operate with digital temperature screen
- Highly efficient, conserving both water and energy use
- The copper and stainless steel heat components are high quality
- The unit is light, compact, and very elegant
- Easy installation
- Instant hot water
What We Don’t
- You can only use it on one appliance with little to moderate demand
- The warranty period is very short and does not cover any damage to the housing unit itself
We highly recommend this unit for use in recreational vehicles or boats. The minimum water and energy requirements are its main selling points, as an outdoor companion where hose resources can be scarce. It is also ideal for use at home.
SioGreen SIO18 comes with cutting-edge patented technology for heating hard water. As the name suggests, it uses far-infrared rays (FIR) and quartz tubes to heat water. This technique is a far departure from heating the water using copper and steel components.
The quartz heating tubes are resistant to scale build-up and water contaminants such as bacteria and algae. It is designed to last longer than the regular water heaters whose elements are plagued with such issues.
- Water output rate of 0.5 (1.9 L) to 4.4 gallons (16.66 L)/minute
- It is built to last a lifetime with minimal to no maintenance required
- It provides 60% more water and energy savings than steel element water heaters
- SioGreen SIO18 can be integrated with an existing traditional heating unit without special adjustments. This is ideal if you are looking to upgrade your heating system.
- The FIR water heater can operate on both electrical and gas systems
- It is compact enough to fit into small bathrooms, cabinets, or kitchens. It can be installed in restaurants or stores for commercial use.
- The manufacturers offer a 30-day money-back guarantee if you are less than 100% satisfied with the heater
- There’s no need to install a venting outlet
- It can serve two output points simultaneously in warmer areas
- Voltage 240V, maximum of 80 amps
- ¾-inch NPT plumbing requirements
- The tank dimensions are 20 x14 x6 Inches
What We Like
- Zero maintenance fees
- The heater uses environmentally friendly recyclable materials
- No corrosion or calcium deposit problems that necessitate flushing
- Smart modulating software that keeps a memory of your temperature preferences and adjusts accordingly
- Works well for a sizeable household and a commercial setting
- The perfect solution to heating well and hard water
What We Don’t
- Compared to metallic heating tanks, the overall water flow is lower with the quartz tubes
- It is one of the most expensive water heaters on the market
At this point, we can only say that the fruits of investing in this infrared unit will be worth it in the long run. If you have a busy household or a growing business, the price of the SioGreen SIO18 is justified. The icing on the cake is that there will not be further maintenance costs.
The Rinnai V series water heaters have seven tankless models meant to be installed purely indoors. These models either use propane or natural gas.
From the table, the only difference between sister V models is in the fuel they run on. The water output per minute remains the same between similar models, regardless of whether they are using propane or natural gas.
- On-demand supply of hot water (as long as there is running water from the inlet)
- Rinnai Control-R 2.0 Wi-Fi module is a mobile app that is used to remotely control your water heaters
- These models are for indoor installation only
- The V94iN/iP/XiN can be installed for commercial use
- The Rinnai Models can generate water temperatures of up to 140℉
- They support simultaneous multiple outlet use
- They operate using the closed combustion system, burning up gas using surrounding air
- Limited warranty of 10 years, including 5 years for the electrical parts and a one-year cover for labor
- The BTU ratings range between 150,000 and 199,000 BTUs
What We Like
- The water from the shower flows out quietly
- Lower electricity bill while the gas bill does not climb upwards
- It serves medium to busy households well
- Easy installation, you can choose to do it yourself with the installation manual
- The water temperature does not change when you are using hot water from multiple outlets
- The remote control via an app makes sure you do not waste your gas in case you forgot to switch it off
- Zero Co2 emissions, which also means they qualify for the tax credit
What We Don’t
- Rinnai units require a vent pipe to condense the units. It is sold separately and it’s quite a price
The Rinnai V series is ideal for use by medium to large households with multiple hot water needs. Families that are looking to save on their water and electricity bills should consider this alternative.
Buyer’s Guide to Frequently-used Technical Terms
GPM or gallons per minute – A unit of measurement for the rate that water flows out of the shower. The maximum federally mandated GPM is 2.5 for a new shower head. Kitchen faucets, on the other hand, are restricted to 2.2 GPM.
Flow rate – The amount of water flowing through a pipe per unit time, which is usually a minute or hour.
Efficiency – Using the least amount of electrical energy or gas to heat the largest volume of water possible.
EF (energy factor) – This is the measure of the efficiency of a water heater. It is found by measuring the amount of water heated in a day versus the unit of fuel consumed on the same day. The higher the energy factor, the more efficient a heater is.
BTU (British Thermal Unit) – The amount of heat it takes to raise 1 pound (0.45 kg) of water by 1℉.
To conclude this in-depth buying guide, as you make up your mind on the kind of hard water heater you would like to purchase, remember to keep in mind the following:
- The source and accessibility of energy
- Operational and maintenance costs
We hope that our analysis has helped you pick out your favorite brands. We are confident that you’ll have a clearer picture of what you need and can find the product that will deliver the results you are hoping for.