Pros and Cons - Tankless Water Heaters

Today, we would like to review some pros and cons of tankless water heaters. Marketed as "Endless Hot Water," it's an easy sell to customers who have experienced a cold shower. Unfortunately, tankless water heaters are often sold to customers without informing them about the possible additional costs and complications they might encounter.

Pros:

• Endless Hot Water - No one likes a cold shower. Families who experience a consistent lack of hot water during crucial times, such as showering, would enjoy the endless hot water that a tankless water heater provides.
• Space Saving - Tankless water heaters are wall-hung and take up significantly less space than standard tank-type heaters. Some are also available for exterior, outdoor-rated installations.
• Options - Tankless water heaters come in options of Electric, Natural Gas, or LP - Propane.

Cons:

• Endless Hot Water? - Why is it both a Pro and a Con? If sized correctly, tankless water heaters can work great. However, as professionals, we often see customers (and other plumbing contractors) undersize tankless units. They are not a one-size-fits-all solution for homes and require specific information for demand and sizing. How many bathrooms are there? Are there any high-flow fixtures like tub fillers for a freestanding or garden tub? Undersizing units often leads customers back to their original problem: cold showers.
• Cost of Unit - Tankless water heaters cost approximately 2 to 2.5 times more for the unit itself (not including installation) compared to a traditional tank-type heater. Yes, you can find them cheaper, but as with most things in life, you get what you pay for. Keep this in mind when considering options and avoid purchasing off-brand units from Amazon or eBay.
• Cost of Installation - Every installation cost can vary depending on the location of your existing water heater. Relocating the unit outdoors will result in running new water or gas lines. The plumbing is often the least costly part of the installation. Hiring an electrician can be the most costly aspect, as described in the next bullet point.
• Electrical Cost - Electric tankless heaters can give homeowners a run for their money. Tankless heaters have a much larger electrical draw than standard tank-type water heaters, which requires significant electrical modifications for larger wiring and sometimes up to 2 to 3 breakers. A typical tankless water heater draws between 40 and 120 amps, depending on the model and its heating capacity, with most requiring a dedicated circuit and a breaker sized accordingly; for reference, a standard electric water heater usually uses around 18.8 amps at 240 volts. If your existing breaker box doesn't have additional breakers for expansion, you might have to upgrade or replace your whole breaker box.
  
• Maintenance Cost - Tankless water heaters must be flushed annually per manufacturers' requirements. If done by a professional, this would cost you $150 - $200 annually. This is something to strongly consider versus a traditional tank-type heater.
• High Maintenance - As described above, you should flush your tankless heater annually. Tankless heaters have small diameter piping that doesn't work well with poor-quality water. Water minerals and calcium can reduce the longevity and effectiveness of the unit. It's highly suggested to have a Water Conditioning and Filtration System when using a tankless water heater (which is another significant cost if you don't currently have one).
• Repairs and Reliability - In comparison to a tank-type water heater, the technology in a tankless heater makes repairs much more complicated. An electric tank-type water heater has approximately six replaceable parts (2 elements, 2 thermostats, an anode rod, and a T&P valve). All these items are stocked by plumbers as well as hardware stores, resulting in quick and inexpensive repairs. Tankless technology includes items like flow sensors and circuit boards that require lengthy diagnosis times and much longer times to order and receive parts. This can leave customers without hot water for extended periods and with much larger plumbing invoices.

We hope you find this information helpful when considering a tankless water heater! We always like to make our customers aware of the possible complications they may face when making important financial decisions for their home. In our experience, tankless water heaters work best in gas applications when sized and designed during new construction. The technology of tankless water heaters improves each year, but when it comes to replacing your tank-type water heater, I always recommend going with a standard tank-type heater.