Want to live greener? Tankless water heaters are one way to get there.
Water heaters are the second-highest source of energy usage in the home. For years, homeowners have depended on 40-60 gallon hot water tanks to provide hot water. There is, however, a growing (and much more energy efficient) option in the market – the tankless water heater – powered by gas or electricity.
At ProSolutions Inc., we stock them, we install them and we maintain them – so, we know a lot about tankless heaters!
Our team thought it would be nice to share what we know after 12+ years of installation, maintenance and repairs on these things in one of the harshest climates they operate in (Alberta). So, read on and find answers to the following questions:
- How does a tankless water heater work?
- Do you run out of hot water with a tankless water heater?
- What is Delta T (ΔT) and why does it matter?
- How big should my tankless water heater be?
- Are tankless water heaters better for the environment?
- Electric vs natural gas tankless water heaters – which is better?
- What is the downside of a tankless water heater?
- Is it worth getting a tankless water heater?
- What is the best tankless hot water heater?
How does a tankless water heater work?
A tankless water heater uses high powered burners, or elements, to rapidly heat up the water as it runs through a heat exchanger. It then delivers it to the hot water outlets that require it. It only works when there is a demand for hot water. That is, when someone turns on a tap, a signal is sent to the heater to ignite gas flow.
Do you run out of hot water with a tankless water heater?
With a tankless water heater, you’ll never run out of hot water, unless the power goes out.
However, it’s important to make sure that your tankless unit has a large enough capacity to handle the demand placed upon it. For example, if several things are operating at once – a shower, a dishwasher – is the unit capable of servicing them all, given the home’s water pressure and the gas flow into the tankless unit?
Delta T (ΔT) – What it is and why it matters
In the heating, cooling & plumbing industry (HVAC), Delta (Δ) is used to express the difference between two related measurements. With a tankless water heater, ΔT is used to show the difference in temperature between water coming into the unit versus water leaving the unit.
A more efficient or powerful unit will be able to increase the ΔT more and, therefore, is a better fit when you have colder water than average entering your home.
For example, if you live in the Edmonton area or another cold climate location, you know that your water is ICE COLD during winter months. The drop in input temperature will make your tankless work harder to reach the proper output temperature.
What does this mean for your hot water supply? A lower input temperature usually results in lower GPM flow (Gallons per Minute) than rated on the unit.
How temperature difference (ΔT) impacts your gallons per minute
The smaller the difference in the temperature you require, the greater the flow. The greater the difference in temperature, the lower your water flow will be.
Let’s look at a real-world example:
California versus Alberta
In Los Angeles your water input temperature might be 60 degrees Fahrenheit (approximately 16 degrees Celsius) while in Edmonton that input temperature could be 40 degrees (approximately 4 degrees Celsius). If the intended output temperature is 120 degrees Fahrenheit (49 degrees Celsius), then the same tankless heater in Edmonton will have to work significantly harder to reach the output temperature than the tankless in Los Angeles. This means that the flow from the tankless water heater in Edmonton will be lower than in LA.
Keep in mind – every degree that you go up, you drop the flow (GPM).
Size and capacity – How big should my tankless water heater be?
If you remember nothing else from our guide, remember this – capacity is everything with water on demand! If the heater you pick cannot meet your family’s maximum need for hot water, you’re going to be in some “HOT WATER” yourself.
The capacity (size) of a tankless water heater is expressed in Gallons Per Minute (GPM). This number represents how much water your tankless water heater can heat in a minute.
But wait, there’s more!
Remember ΔT? Many manufacturers rate their tankless heaters’ GPM capacity with different ΔT values. That is, they pick a water input temperature and base their rating on that temperature. The problem is – this estimate could be unrealistic for your climate. Not only that, but the heated temperature will typically be lower than what you have your homes’ standard hot water tank set at (mine is set at 150°F).
So, watch for the temperature that manufacturers rate their GPM capacity at and make sure it will suit your personal situation.
How much GPM capacity does my family need?
Here are our recommendations, depending on family size.
2 – 3 person household: 9 GPM
4 – 5 person household: 10 GPM
5+ person household: 11.1 GPM at 70 degree heat rise (approximately 4 GPM in Edmonton with 40 degree input)
These recommendations are for average water use. If your household is heavy on the hot water, just go up in size. Or, if you want to prepare for the future, go for the largest option available.
An average shower uses 2-3GPM. If you have rain/waterfall-style showerheads expect to use much more. Don’t forget about dishwashers, washing machines, or just filing a large bathtub. These all add high demands on hot water for short periods of time so doing two or three activities at once can require a fairly high GMP capacity.
The best thing to do is talk to a professional about the real-world performance of tankless water heaters. They should be able to give you specific units that perform well with your usage and climate taken into consideration.
Can a tankless water heater be too big?
No, honestly, they are not perfect for all situations so until they reach that point, talking about too much capacity isn’t important.
Don’t forget about the resale value of your home. Tankless does add value to the home, but only if the capacity is going to work for the family moving in.
Are tankless water heaters better for the environment?
Yes! Some units are rated as high as 98% efficiency! Compared to a traditional hot water tank heater, they are 35 – 80% more efficient.
In fact, Natural Resources Canada’s Water Heater Guide states that gas-fired tankless heaters have energy factors (EFs) that range from 0.64 to 0.98 (average 0.85); a marked improvement in efficiency over tank units ranging from 0.53 to 0.70 (average 0.62).
Which is better electric or gas tankless water heater?
Tankless water heaters may be electrically-powered or natural gas-powered units. Each has its own pros and cons.
Electric tankless water heater pros and cons
Electrical water on demand tanks are easy to install and have a long service life. However, additional advantages and disadvantages also require consideration.
- Less prone to hard water and sediment deposits
- Do not require venting
- Do not emit greenhouse gases at your home’s location
- You may need electrical upgrades for installation purposes
- Are not as energy efficient as gas-powered units (expect three to five times the operating costs in Alberta)
Tankless gas water heater pros and cons
Gas tankless water heaters are more complex to install. However, they also have many benefits.
- Have significantly lower total costs over their life (unit + maintenance + gas)
- Are easier to repair and replace parts on
- Produce higher flow rates than electrical units
- Produce minimal levels of greenhouse gases
- More prone to hard water and sediment deposits
- Require proper venting
At ProSolutions Inc., we prefer natural gas tankless water heaters, as operating costs are significantly reduced because of the difference in utility costs in Alberta. Harmful emissions from high-efficiency gas water on demand units are minimal as well.
Purchase factors that may impact your decision
You might be wondering – What is the downside of a tankless water heater? The biggest downside to a tankless water heater is the initial cost.
Before making your decision to purchase a tankless heater, it’s important to consider these factors:
- A tankless unit will cost 2 – 3 times as much as a conventional water heater. i.e. a regular storage tank costs $1,100 to $1,800. A tankless unit will range from $2,900 to $5,000 and up.
- Tankless water heaters are more complex than conventional units. They require deep knowledge of how they operate, and how to install them.
- Switching from a conventional tank unit to a tankless unit will likely require rerouting gas lines – another added cost.
- A tankless heater will typically need a 1.9 centimetre (3/4 inch) supply line compared with the 1.2 centimetres (1/2 inch) line for a conventional water heater because of the need for increased gas volume.
- Plumbing issues can also arise. Water lines may need shifting and you’ll need to ensure that the water pressure is high enough to supply sufficient cold water to the heat exchanger when demand for hot water comes from several sources.
- Tankless water heaters need pipes flushed annually, depending on the hardness of the water and sediment build-up. You can do it yourself, or have us do it with our Service Partner Plan.
- Extremely cold water temperatures, like we have in Edmonton, can be hard on tankless units.
At ProSolutions Inc. we recognize that several factors are involved in whether to move to a tankless water heater rather than the traditional hot water tank. While there are savings on operating costs, the initial cost outlay for the tankless units is considerably higher. For some people, knowing that you can have a continuous supply of hot water available can be a convincing argument.
Is a tankless water heater worth it?
A tankless water heater is not right for everyone – don’t let a plumber tell you otherwise.
The truth is that a tankless hot water system, while greatly improved, is best for homes where high use of water is not common. If any of the following apply to you, an on-demand hot water system probably is not right for you.
- You have a large tub/jacuzzi tub and enjoy soaking in it often
- You have high-volume rain heads or body jets in your showers
- Your ground/city water comes in at very cold temperatures most of the year (ie. NWT, Yukon, etc).
On the other hand, if a tankless system is right for you, it can have many perks and result in cost savings over time. For instance, a standard hot water tank (a tank with hot water that is heated and reheated as required) lasts 7 – 10+ years with current hard water conditions with virtually no maintenance, if you so choose, unless you have issues with the pilot light. A tankless unit, however, can last from 20 – 30 years, more than double that of a conventional unit.
In addition, if too many people have showers, or someone turns on the dishwasher, a traditional hot water tank can run out of hot water – as we all know when a hot shower suddenly turns cold. There’s then a lag time before the tank reheats and hot water is ready again. With a quality tankless heater one thing is certain – even with household members using the same shower one after the other, you will never run out of hot water.
Best tankless water heater for cold climates
Here is our recommendation for the best tankless hot water system.
- Best Warranty – 25 years on the heat exchanger
- Highest output available right now
- Single or double piped available (great venting flexibility)
- Reliable and easier to get replacement parts for, especially in Canada
Below are some additional options to consider if you have needs beyond the capabilities of a standard tankless system.
Domestic Water Heat Recovery Coil
This option is great for colder climates. It takes drain water and uses it to increase the input temperature of the water, allowing the heater to work less to get to the desired temperature. Cost: approximately $1,500.
A hybrid system is another great option. With a hybrid system, an electric tank heater holding tank is added so that you always have hot water in any situation (excluding power failure).
Why you might consider a tankless water heater from ProSolutions Inc.
- Always hot water when needed
- Operating costs up to 50% less than conventional units (average 25 – 35% according to the US Department of Energy.) With an Energy Star unit that uses a secondary heat exchanger, energy usage can be cut another 9%
- Tankless units last from 20 – 30 years, double that of traditional units
- Compact designed tankless units minimize space requirements
- Replacement parts are easily available; condensing gas technology leads to very high efficiency (96%)
- Smart technology monitors performance, efficiency and troubleshooting
- Tankless units use less than 41 gallons of hot water per day. Compared to conventional tank units tankless systems are 24 – 34% more efficient
- Conventional tank heaters generate higher utility bills
- No standby energy losses like those with conventional tank heaters
Low-interest financing is available from most plumbing companies
Considering a tankless water heater for your home but don’t have the money up front? Most plumbing companies, including ProSolutions Inc., offer financing options to help you improve your home without needing to break the bank.
At ProSolutions Inc., we offer several home improvement financing options. With quick and easy approvals, economical interest rates, flexible payment plans and no money down, these options are a great solution for this long-term investment.
Want more information about tankless water heaters from ProSolutions Inc.? Call us. We’d love to talk to you and discuss your situation. And don’t forget – at ProSolutions Inc. we have financing options to make sure you get the home comfort you deserve. Call us today.