Is Your Gas Line Ready for a Tankless Water Heater? Here’s What You Need to Know

Is Your Gas Line Ready for a Tankless Water Heater? Here’s What You Need to Know

If you’re considering upgrading your water heater to a tankless model, you might wonder if your gas line can handle it. 

Tankless water heaters are more energy-efficient and space-saving than traditional tank models. Unfortunately, they also require more gas to heat water on demand. 

That’s why this post is diving into the need-to-knows of gas lines and tankless water heaters. 

Does the gas line size matter?

The answer is yes, it does. The gas line size determines how much gas can flow to your home’s tankless water heater and other gas appliances. 

Impact of Gas Line Size on Tankless Water Heater Performance

When your gas line is not sized properly, it will cause a fluctuating inlet gas pressure at your tankless water heater, affecting its modulation and stability. This means you might experience temperature variations or cold water sandwiches when using hot water.

If your gas line is too small, it will cause a low inlet gas pressure at your tankless water heater, reducing its heating capacity and output temperature. This means you might not get enough or consistent hot water for your needs.

If your gas line is too big, it will cause a high inlet gas pressure at your tankless water heater, increasing fuel consumption and emissions. This means that you might waste gas and money and harm the environment.

Ideal Gas Line Size for a Water Heater

Different tankless water heaters models have different minimum and maximum inlet gas pressures at which they can operate. Before installing your tankless water heater, inspect the product specifications or user manual for this information.

Some of the factors that can impact the needed gas line size for your water heater include: 

  • The British Thermal Unit (BTU) rating of your tankless water heater. This is the amount of heat that the unit can produce per hour. The higher the BTU rating, the more gas it needs.
  • The BTU ratings of your other gas appliances. You need to consider the total gas demand of all the appliances that share the same gas line as your tankless water heater. You can find these ratings on the labels or manuals of your appliances.
  • The length and diameter of the gas line. The longer and narrower the pipe, the more resistance it creates to the gas flow.
  • The natural gas supply pressure. This is the pressure at which the gas is delivered to your home by the utility company. The higher the pressure, the more gas can flow through the pipe.

To determine if your existing gas line can support your tankless water heater, you need to compare the total BTU load of your appliances and the water heater with the capacity of your gas line. 

If the total BTU load is less than or equal to the capacity of your gas line, then you are good to go. 

If it exceeds your current pipe size and length capacity, you need to upgrade your gas line to a larger diameter or a shorter length.

What should I know before installing my tankless water heater?

Before installing your tankless water heater, you must answer important questions about your home’s gas line. 

  • What is the BTU rating of the tankless water heater and your other gas appliances?
  • What is the natural gas supply pressure for your system?
  • What is the existing gas line size and length for your system?
  • What are the inlet gas pressure requirements for your tankless water heater model?

Installing a tankless water heater can be a great way to save energy, space, and money on your hot water bills. However, you need to make sure that your gas line can support the high BTU demand of your tankless water heater without compromising its performance and efficiency.

Unless you are very comfortable in this arena, hiring a licensed plumber or contractor is the best way to do this. 

So, if you are in the market for a tankless water heater, check out Marey, one of the leading brands in innovative and eco-friendly water heating solutions. 

We offer a wide range of high-quality electric and gas tankless water heaters that suit different needs and budgets. 

Visit us today!

Photo by Jordan Sanchez on Unsplash

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