Are you considering a switch to a tankless water heater for your Las Vegas, NV, home? If so, you should know you can’t size one like a storage tank model. That’s because tankless water heaters operate solely based on their flow rate. By contrast, a storage tank model depends on maintaining sufficient hot water reserves to meet your demand. If you choose the wrong size tankless water heater, it will struggle to meet your needs. To avoid that, follow these five tips to select the proper tankless water heater size.
1. Choose Between Natural Gas and Electric
When choosing between a natural gas and an electric water heater, consider your home’s needs. Natural gas heaters typically heat water faster and may be more cost-effective, especially if you have a gas line already. They also work during power outages, offering reliability. Electric water heaters, however, can be easier to install and are known for their energy efficiency, particularly in models with a high Energy Factor (EF).
2. Calculate Your Hot Water Demand
The first thing you need to know to choose the right tankless water heater size is your home’s hot water demand. Figuring that out begins with thinking about how, when, and where your home uses hot water. Remember, a tankless water heater produces all your hot water on the fly, with no stored buffer to help. However, your demand isn’t simply the sum of the flow rates of your hot water taps and appliances. It’s the sum of the flow rates of the most water-used taps and appliances you expect to use simultaneously.
Begin by listing all the hot water-using fixtures and appliances in your home. Next, determine the flow rate of each one. Your appliances will include this information in their documentation. However, only some of your fixtures will have their flow rate imprinted on them. Add as much of the information as you can find to your list. For the fixtures that don’t have flow rates listed, you can use estimates or measure them yourself. The following are some decent estimates you can use:
- Bathroom faucets use 1.5 GPM or less
- Kitchen faucets use 2.2 GPM or less
- Showers use approximately 2.5 GPM
- Dishwashers and clothes washers use approximately 3 GPM
Then, think about your average day. Do multiple people in your home shower at the same time? Do you routinely run your dishwasher and washing machine concurrently? Using your listed values, determine what combination of activities equals the highest total flow rate. The number you get is your home’s peak hot water demand.
3. Measure Your Inlet Water Temperature
With your peak flow rate figured out, the next thing you must consider is temperature rise. That’s the difference between your home’s inlet water temperature and how hot you want your water to get. On average, most homes here in Las Vegas have an inlet temperature between 52 and 60 degrees. However, it would be best if you didn’t assume that yours matches those figures. Instead, use a thermometer to measure your incoming water temperature as close to where it enters your home as possible. The best time to do this is at the end of December. That’s when your water will be at its coldest for the year. Then, take the temperature you get and subtract it from 120 degrees, the standard residential hot water temperature.
You will find that tankless water heaters list their flow rates as a function of temperature rise. They’ll sometimes list their temperature rise values as ΔT. You’ll notice multiple flow rates listed based on a range of ΔT values. You need a water heater that meets your home’s peak demand flow rate at its largest seasonal temperature rise.
4. Consider Costs
At this point, you may have run into one of two problems. If your home has high hot water demand, you may not have found a water heater to supply your required flow rate. Or, if you did, it may be far more expensive than you’d like. If you’re in that situation, your next step is to decide if splitting your home’s demand is a better option. For example, you might split your hot water system in half. You might put a single shower, dishwasher, and kitchen sink in one segment. In the other segment, you may include another shower, your washing machine, and your remaining sinks. Doing that may lower your peak hot water demand. Then, you could install two smaller tankless heaters to serve each segment.
Alternatively, you may want to add more than a single small tankless system to serve individual hot water loads. For example, you could put one in your laundry room and another in your kitchen. Then, you’d serve your home’s remaining hot water needs from a single centralized unit. If you choose to split your hot water service this way, it also creates another possibility. You could mix and match electric and gas-fired heaters. You could use small electric models for individual hot water supplies and a gas-fired one for your main. That will minimize your overall costs by reducing the total unit prices and avoiding the need to add gas piping.
5. Solicit Installation Quotes
Once you know how many tankless water heaters you need and what size, you can get installation quotes. Different plumbing companies carry different water heaters, which will affect the price. They also have different labor costs that factor in. If you have a preferred water heater brand, find out if the plumbers you’re considering will install it. Some will install models they don’t typically carry at your request.
At this point, you should reevaluate your decisions regarding your sizing options. The plumbers providing the quotes should give you some input about whether you’ve made a sound plan. For example, they may determine that your segmenting plan is cost-prohibitive. At that point, consider their proposed alternatives carefully. Reworking your plumbing unnecessarily as part of your installation can significantly increase your cost.
Your Local Water Heater Experts
If you’re interested in a tankless water heater in Las Vegas, Bumble Breeze is the best place to call. Since 2018, we’ve been the plumber locals trust with their home’s critical water systems. We’re family-owned and operated and focus on delivering quality services at affordable prices. We’re your one-stop shop for all your plumbing needs, from leak detection to water testing, gas piping, and drain services. We also offer comprehensive HVAC services to help you keep your home comfortable year-round. And if you own a local business, we provide commercial services, too.
If you want a new tankless water heater for your Las Vegas home or have any questions on sizing, call Bumble Breeze!
