When it comes to home improvement projects, installing a water heater might not seem as complex as remodeling a kitchen or rewiring your electrical system. But in Knoxville, TN, water heater installations are often done incorrectly, leading to higher energy bills, reduced appliance lifespan, and even safety hazards. Whether it’s due to DIY missteps or hiring underqualified contractors, many homeowners and businesses in the area make critical mistakes during installation. Here’s a deep dive into what Knoxville is getting wrong with water heater installations—and how to do it right.

1. Choosing the Wrong Size Water Heater

One of the most common mistakes in Knoxville is selecting a water heater that doesn't meet the home's needs. An undersized unit will run constantly, struggling to keep up with demand, while an oversized unit consumes more energy than necessary.

What to Do Instead: Have a professional plumber calculate the peak usage in your household or business and recommend the appropriate tank size or flow rate if you're considering a tankless system. This small step can save you from years of inefficiency and discomfort.

2. Ignoring Local Building Codes and Permit Requirements

Knoxville has specific building codes related to water heater installation, especially concerning venting, placement, and safety features. Unfortunately, many installations are done without proper permits or inspections, which can void warranties and insurance claims.

What to Do Instead: Always pull a permit for a water heater installation and ensure your installer is licensed and familiar with Knoxville and Knox County plumbing codes. It’s not just about legality—it’s about safety and long-term functionality.

3. Poor Placement and Ventilation

Another frequent oversight in Knoxville homes and businesses is poor placement of the unit. Water heaters installed in cramped closets or areas without proper ventilation can overheat or create dangerous conditions, especially with gas models that require combustion air.

What to Do Instead: Install your water heater in a well-ventilated space with proper clearance and access for future maintenance. For gas heaters, ensure proper exhaust venting to avoid carbon monoxide buildup.

4. Incorrect Temperature Settings

Setting your water heater temperature too high or too low can cause problems. Many Knoxville homeowners leave their settings at factory default (usually 140°F), which increases the risk of scalding and energy waste.

What to Do Instead: The U.S. Department of Energy recommends setting your water heater to 120°F. This provides hot water while preventing burns and improving efficiency.

5. Skipping Expansion Tanks

In homes with closed water systems (common in Knoxville suburbs), failing to install an expansion tank can lead to excess pressure and damaged plumbing.

What to Do Instead: If your system requires it, add an expansion tank during installation. This inexpensive addition can prevent costly damage to pipes, valves, and the water heater itself.

6. DIY Installations Gone Wrong

Knoxville homeowners trying to save money sometimes take on water heater installations themselves without understanding plumbing or electrical codes. This often results in leaks, electrical hazards, or inefficient operation.

What to Do Instead: Leave water heater installations to licensed professionals. Even if you're handy around the house, the risk isn’t worth the reward when you're dealing with pressurized tanks and electrical connections.

7. Not Considering Tankless Options

Traditional tank-style heaters are common in Knoxville, but many homeowners miss out on the benefits of tankless systems because they aren’t aware of their advantages or assume they’re too expensive.

What to Do Instead: Evaluate your household's hot water usage and discuss tankless options with a qualified installer. These systems offer endless hot water, lower energy bills, and longer lifespans when properly installed.

8. Neglecting Regular Maintenance

A water heater is a long-term investment, but Knoxville residents often neglect routine maintenance like flushing sediment from tanks or checking the anode rod. This oversight shortens the lifespan of the unit.

What to Do Instead: Schedule annual maintenance with a local plumber. They’ll flush the tank, inspect components, and catch issues early before they become expensive problems.

9. Improper Electrical and Gas Connections

Incorrect wiring or loose gas lines are not just code violations—they’re dangerous. Faulty connections can result in fires, gas leaks, or electric shock.

What to Do Instead: Hire professionals who know how to properly ground electrical systems and seal gas connections. Safety should never be compromised for speed or cost-cutting.

10. No Drain Pan or Improper Drainage

In homes with water heaters installed above living spaces, failing to use a drain pan or direct drainage properly can lead to water damage if the tank leaks.

What to Do Instead: Install a drain pan with a connected overflow pipe that directs water safely to a floor drain or outside. It’s a simple precaution that prevents major damage.

Conclusion: Getting It Right in Knoxville

Water heater installations are often underestimated, but as Knoxville homeowners are learning, getting it wrong can have serious consequences. From sizing and placement to code compliance and maintenance, every detail matters.

The good news? These mistakes are entirely avoidable with proper planning and professional help. Whether you’re replacing an outdated unit or building a new home, working with licensed, local plumbers ensures your system runs safely and efficiently for years to come.

If you’re ready to get your water heater installation done the right way, reach out to a trusted Knoxville plumbing expert. Your comfort, safety, and wallet will thank you.

‍