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Why Your Tankless Water Heater Takes Time to Heat Water

Tankless Water Heating problems

When you made the switch to a tankless water heater, you were likely drawn by the promise of endless hot water, energy efficiency, and space savings.

However, if you’ve found yourself tapping your foot impatiently as you wait for the water to warm up, you’re not alone, as Calgary’s Tankless Water Heater Experts we know about problems and how to solve them.

Despite their many benefits, tankless water heaters can sometimes take longer than expected to deliver hot water to your tap.

This delay can be puzzling and frustrating, especially when you’re in a hurry. In this post, we’ll explore the reasons behind these delays in heating water and provide insights into how tankless water heaters operate.

From the size and capacity of your unit to the distance water travels through your pipes, several factors can affect how quickly you get hot water. We’ll also delve into solutions and preventive measures to help you minimize wait times and maximize the efficiency of your tankless water heater.

Whether you’re considering making the switch or looking to optimize your current setup, we, as Calgary Plumbers for over 50 years can help in understanding these aspects can help you enjoy the full benefits of going tankless.

Factors Affecting Heating Time

Size and Capacity of the Unit

The capacity of a tankless water heater to deliver hot water efficiently is contingent upon its size relative to the demand placed upon it.

A unit that is too small for a household’s needs may struggle to provide hot water quickly, especially during peak usage times when multiple hot water applications are in use simultaneously.

Flow Rate vs. Demand

Tankless water heaters activate based on the flow rate of water through the unit.

If multiple outlets are in use simultaneously, the heater might struggle to meet the high demand, leading to delays in heating.

Distance Between Heater and Tap

The length of the path water must travel from the heater to the tap significantly affects the time it takes for hot water to arrive.

Longer distances mean that users will have to wait longer for hot water, as the heat is gradually lost while the water travels through the pipes.

Type of Installation

The efficiency of tankless water heaters can also be affected by whether they are installed centrally or closer to the point of use.

Central installations may result in longer wait times for hot water.

Mineral Buildup

In areas with hard water such as Calgary, mineral deposits can accumulate inside the heater, reducing its efficiency and capacity to heat water quickly.

68628623 – hard water calcium deposit on chrome tap

This buildup can also occur in the pipes, further delaying hot water delivery. Over time, hard water can lead to the accumulation of minerals inside the tankless water heater, forming scale buildup. This not only reduces the efficiency of the heater but also impedes its ability to quickly heat the water. Regular maintenance is required to address this issue and maintain optimal performance.


Low Gas Pressure

For gas-powered tankless water heaters, adequate gas pressure is essential for the unit to function efficiently.

If the gas pressure is too low, the water heater will not be able to reach the desired temperature swiftly, leading to delays in heating the water.

Low Incoming Water Temperature

The colder the incoming water, the longer it takes for the tankless water heater to heat it to the desired temperature. This is particularly noticeable inour Calgary winters.

Gas Line Size

For gas-powered tankless water heaters, an inadequately sized gas line can restrict the flow of gas to the unit, limiting its ability to heat water quickly.

Electrical Capacity

Electric tankless water heaters require a significant amount of electrical power to operate efficiently. Insufficient electrical capacity can lead to slower heating times.

Improper Settings

Sometimes, the issue can be as simple as the temperature settings being too high, which makes the heater work longer to reach the set temperature, especially if the difference between the incoming water temperature and the set temperature is large.

Wear and Tear

Over time, components of the tankless water heater can wear out or malfunction, leading to decreased efficiency and longer wait times for hot water.

Solutions to Improve Heating Time

Upgrading Your Water Heater

If your current tankless water heater is unable to meet the hot water demands of your household, it may be time to consider upgrading to a larger unit. Consulting with a professional can help determine the appropriate size and capacity for your needs, ensuring that hot water is delivered more quickly.

Installing a Recirculation Pump

A recirculation pump can significantly reduce the wait time for hot water by keeping hot water circulating through the pipes, thus ensuring that it is readily available at the tap. This solution is particularly effective in homes with long distances between the water heater and the points of use.

Regular Maintenance and Descaling

To prevent mineral buildup and maintain the efficiency of your tankless water heater, regular maintenance, including descaling, is essential. Descaling involves flushing out mineral deposits from the heater, which can improve its performance and reduce heating delays.

Adjusting Gas Pressure

For gas-powered units, ensuring that the gas pressure is set to the optimal level can enhance the heater’s efficiency. This adjustment should only be performed by a certified technician to avoid potential hazards and ensure that the water heater operates safely and effectively.

Preventive Measures

Importance of Regular Maintenance

Regular maintenance is crucial for the longevity and efficiency of your tankless water heater. This includes periodic inspections, cleaning, and descaling to prevent issues that could lead to heating delays.

Benefits of Installing a Water Softener

In areas with hard water, installing a water softener can significantly reduce mineral buildup in your tankless water heater. This not only helps maintain the heater’s efficiency but also extends its lifespan by preventing scale accumulation.

Optimal Installation for Efficiency

Proper installation of your tankless water heater can greatly affect its performance. Ensuring that the unit is installed as close as possible to the main points of use can reduce the distance hot water must travel, thereby decreasing the wait time for hot water.

By addressing these factors and implementing the suggested solutions, homeowners can significantly improve the heating time of their tankless water heaters, enjoying the convenience of quick and efficient hot water delivery.

George Pinel
George Pinel

Master Plumber

I have been involved in this family owned business for 33 years now.

It has always been and will continue to be the core focus of Instant Plumbing & Heating to provide a long lasting relationship with our customers based on trust and integrity of our service and products.

This achieved by using the best quality materials. I as a business owner continue to mentor and treat my staff with the highest regard and respect, this interns helps them deliver to the client great quality workmanship and service.

It is our professional goal to leave a situation better than when we arrived both in how we do our work and in how you feel for having chosen us to do your work, we are in the anxiety reduction business using plumbing and heating service work to do it.

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