If you’re looking to improve your household’s energy efficiency without compromising on comfort and convenience, upgrading to a tankless water heater is a great way to accomplish your goals. Converting from a traditional tank-style water heater to a modern tankless system is possible in most homes, and the long-term energy savings associated with making this switch can be significant.
These projects aren’t suitable for inexperienced amateurs, however, and require the advanced know-how of professional installers who are familiar with local building codes as well as the many steps needed to get the job done right.
This guide provides an overview of what to expect if you decide to replace your home’s existing water heater tank with a new tankless unit.
Quick Takeaways
- Making the switch to a tankless water heater unit is possible in most residences.
- When upgrading a gas-powered water heater, an upgrade to the connected gas plumbing may also be required.
- For electric water heaters, the electrical service panel may need additional capacity.
- The existing water heater’s ventilation system could also need modification.
- Proper sizing (GPM + temperature rise) of the new tankless system is critical.
- Professional installation ensures safe, code-compliant conversion.
- Upfront costs are usually higher than standard tank replacement, but lower energy costs are usually realized later on.
Can You Convert a Tank Water Heater to Tankless?
The short answer is yes, converting from a tank-style water heater to a tankless unit is possible in most cases. However, it’s important to understand that making the conversion is generally much more complicated than simply removing an old water heater tank and installing a new tankless unit in its place.
To make the conversion from tank-style to tankless, a skilled plumber must first remove the existing water heater tank. The gas or electrical connections may require updating, the ventilation system could need adjustment and the associated plumbing lines might benefit from modification.
The new unit must be properly sized based on the property’s water usage levels, and the installation work must be performed to the highest professional standards.
These important tasks are best handled by knowledgeable plumbers and should be left up to experienced personnel only.
Step 1: Removing the Existing Tank Water Heater
The first step in the process of updating a water heater is removing the existing unit. The unit must be disconnected from the gas or electrical supply and drained of water.
The gas or electrical connections and the surrounding plumbing system should then be evaluated for condition and compatibility with the new water heater unit.
Step 2: Upgrading the Gas Line or Electrical System
Even in relatively new homes, the existing gas plumbing or electrical wiring may not be suitable for use with a tankless water heater due to size, location or general condition. Making repairs to or completely replacing these components must be performed before installing the new tankless system.
Gas Line Upgrades
Tankless water heaters are designed to supply large quantities of water at a moment’s notice, and this means they utilize more fuel during their brief periods of operation. Installing new, larger-diameter gas piping to accommodate the increased peak demand is often necessary when converting to tankless.
Electrical Panel Considerations
For the same reasons mentioned above, electric tankless water heater systems often require higher amperage connections than traditional water heaters. New breakers or other modifications to the electrical panel and wiring system are a must.
Step 3: Modifying Venting Requirements
Tankless water heaters operate using specialized venting systems designed to accommodate their higher energy usage levels. While most tank-style units vent combustion gases and condensation vertically through the roof, tankless systems may vent through walls. Tankless water heaters also rely on sealed vent systems instead of vent piping that’s open to the atmosphere.
Proper venting of gas-fueled water heaters is critical to prevent the accumulation of carbon monoxide and other harmful gases. Water heaters that run on electricity don’t require venting because they don’t create combustion gases.
Step 4: Adjusting Plumbing Connections
In addition to power and venting modifications, going tankless could mean that larger-diameter water piping is in order. The unit itself may also need to be relocated to a more convenient spot on a closet wall or inside a crawl space instead of in a dedicated utility or mechanical room. New isolation valves and service ports may be required as well.
Step 5: Properly Sizing the New Tankless Water Heater
As is the case with all household appliances, tankless water heaters must be properly sized for optimal performance. Criteria for selecting a new tankless unit include the peak gallons per minute the household is expected to need and the temperature rise based on Tampa groundwater temperature.
Installing an oversized tank may seem like a smart idea, but doing so can lead to higher-than-necessary energy usage. Undersizing the unit may reduce the initial cost but could result in a system that’s unable to create sufficient quantities of hot water during times of peak demand.
Step 6: Installing the New Tankless Water Heater Unit
The final step is conducting the actual installation of the new tankless unit. This task should be performed by a licensed plumber with knowledge of the permitting and building code specifications in the area. The new system should also be tested for functionality and leaks as part of the setup process.
How Much Does it Cost to Convert to Tankless?
The costs associated with converting to a tankless water heater vary greatly from job to job. The conversion process involves many more steps than simply removing an old tank and installing a new one, and all these steps translate to significant time and expense.
The top expenses that most homeowners will encounter include:
- Equipment costs
- Gas line upgrades
- Venting modifications
- Electrical upgrades
- Labor and permitting fees
Benefits of Converting to Tankless
Despite the greater initial financial outlay, the advantages of utilizing a modern tankless water heater are many.
Most homeowners find that their tankless systems offer:
- Nearly limitless quantities of hot water
- Improved energy efficiency
- Longer lifespan
- Space savings
- Reduced standby heat loss
When Converting to Tankless May Not Make Sense
Converting to a tankless water heater is beneficial in many situations, but it may not be a good idea for all homeowners.
A few reasons to think twice about making the switch include:
- Limited gas supply capacity
- Insufficient electrical panel space
- Very low hot water demand
- Budgetary considerations
Common Mistakes to Avoid During a Tankless Conversion
Like most home renovation and upgrade projects, installing a tankless water heater comes with numerous pitfalls that should be avoided.
A few of the top mistakes include:
- Choosing a tankless water heater unit based on price alone
- Ignoring gas capacity constraints
- Improperly calculating the expected peak demand and temperature rise
- Attempting DIY installation
- Failing to obtain the proper permits
FAQs About Converting to a Tankless Water Heater
Is it expensive to convert to a tankless water heater?
Converting to a tankless water heater can cost $5,000 or more. A majority of homeowners would find this to be a significant household expense.
How long does tankless conversion take?
Most tankless water heater conversions can be performed in a single business day once the new unit and all necessary supplies are in hand.
Will I need a new gas line for a tankless system?
If you’re converting from an electric water heater to a gas-powered model or your new system requires additional gas capacity, a new gas line will be required.
Can I convert to electric tankless instead of gas?
If your home’s electrical panel can accommodate the increased load, going from a traditional gas water heater to an electric tankless model should be no problem.
Will converting to tankless increase my home’s value?
It’s impossible to quantify an exact increase in home value associated with a water heater conversion, but it’s certainly likely to add value to almost any home. A new tankless water heater could also make your home more desirable to prospective buyers if you’re planning to sell in the near future.
How long do tankless water heaters last?
A tankless water heater can be expected to last between 15 and 20 years when properly maintained and regularly serviced.
Ready to Convert to Tankless in Tampa, FL?
Benjamin Franklin Plumbing provides professional tankless water heater services throughout Tampa, FL and surrounding areas. Our licensed plumbers are capable of evaluating your property’s gas supply, electrical system, venting and plumbing to ensure safe, code-compliant installation of your new tankless water heater system.
If you’re ready to upgrade to endless hot water, call Benjamin Franklin Plumbing — the Punctual Plumbers — and schedule your tankless water heater conversion today.