Tankless Water Heater

Are you tired of running out of hot water in the middle of a shower? Look no further than First Chicago Plumbing for your tankless water heater replacement needs! Our expert technicians are experienced in installing and servicing tankless water heaters for your home or business. Not only will you never run out of hot water again, but you’ll also save space and energy with a tankless water heater. Plus, with our honest and direct service, you’ll never have to worry about any surprises or hidden fees.

Main Advantages Of A Tankless Unit

1. Tankless water heaters are 22% more energy efficient than regular storage tank water heaters.
2. Tankless water heaters last longer, with an average lifespan of 20-30 years compared to 10-15 years for tank water heaters.
3. You can save up to $100 per year on your utility bills with a tankless water heater.
4. Tankless units are smaller in size, making them perfect for homes with limited spacing like small condos and townhouses where space is limited and it’s hard to service or replace tank water heaters.
5. Tankless water heaters cannot flood your home, which is a major concern with tank water heaters that can crack and flood homes or even neighboring condos. This is because tankless water heaters don’t store water.

At First Chicago Plumbing, we understand that a water heater replacement can be a big investment. That’s why we offer free estimates to help ease your mind and ensure that you’re getting the best service possible. Our licensed, insured, and bonded team is committed to providing prompt, high-quality work that is tailored to your specific needs. Whether you’re looking to replace your old water heater or upgrade to a more energy-efficient option, we’ve got you covered in the Chicago area and North Chicago suburbs. So why wait? Call us today to schedule your consultation!

Common Problems with Tankless Water Heaters

Tankless water heaters are designed to provide hot water on demand, improving energy efficiency and saving space. But unlike traditional tank-style heaters, they come with a distinct set of technical and operational challenges. Many of these issues are exclusive to tankless systems due to their design, electronic components, and flow-dependent activation. If not installed correctly or maintained regularly, performance problems can quickly arise—often catching homeowners off guard.

• Cold Water Sandwich Effect: This occurs when hot water is used briefly, turned off, and then turned back on soon after. The initial burst is warm, followed by a few seconds of cold water before heat resumes. This happens because the water in the pipe from the previous use is still hot, but the heater needs a moment to reignite and start heating again.
• Minimum Flow Rate Requirement: Tankless units only activate if the flow of water meets a specific threshold—typically around 0.5 to 0.75 gallons per minute. If you’re trying to use hot water at a low trickle (e.g., hand-washing or shaving), the system may not turn on at all. This issue doesn’t affect tank heaters, which keep a reserve of hot water available regardless of flow.
• Overload During High Demand: These systems are sized based on how many gallons per minute (GPM) they can handle. Running multiple showers or appliances simultaneously can exceed the unit’s capacity, leading to fluctuating water temperature or system shutdown. Unlike tank models, there’s no buffer of stored hot water to rely on.
• Mineral Buildup on Heat Exchanger (Scaling): Hard water leads to calcium and magnesium buildup on the heat exchanger—a critical component in tankless systems. This buildup reduces heating efficiency and can cause overheating errors or total failure over time. Traditional tanks can also suffer from scaling, but tankless units are more sensitive due to the narrow piping and high-efficiency heat transfer design.
• Delayed Hot Water Delivery: Tankless systems heat water only when needed, which adds a short delay while cold water in the pipes is flushed out. Homes with long pipe runs between the heater and faucets may notice even longer waits for hot water, especially if the unit is located far from bathrooms or kitchens.
• Ignition and Sensor Failures: Tankless heaters rely on complex electronics—flow sensors, ignition switches, flame sensors, and control boards—to operate. These parts are more prone to error than the simple thermostats and gas valves in tank units. A fault in any of these components can stop the unit from producing hot water entirely.
• Venting and Air Supply Issues: Tankless systems require high-efficiency venting and proper air intake. Poor installation can cause backdrafting or combustion errors. In some cases, homes may not have the right setup to support a tankless unit without significant modifications.

Tankless heaters can be a reliable upgrade—but they aren’t “set it and forget it.” Regular flushing, water softening, and proper sizing are critical to prevent these issues. If your system is underperforming, it’s worth having a licensed technician inspect it for tankless-specific problems.

Why Call First Chicago Plumbing to Solve Tankless Water Heater Problems?

Tankless water heaters aren’t like traditional systems—they need precision, technical know-how, and attention to detail. At First Chicago Plumbing, we specialize in diagnosing and fixing issues that are unique to tankless units. Our team understands the specific triggers behind problems like flow rate failures, cold water bursts, and scaling that can quietly damage your system.

Here’s why you should call us:

• We know the tech: Tankless systems rely on advanced sensors, control boards, and ignition systems. We troubleshoot electronic faults others miss.
• We solve the “cold water sandwich”: We’ll inspect your installation and recommend smart upgrades—like recirculation pumps or buffer tanks—to eliminate frustrating temperature swings.
• We size systems right: If your unit shuts down under heavy use, we’ll assess your home’s water demands and recommend the right GPM capacity to avoid overload.
• We tackle hard water damage: Chicago’s hard water can ruin heat exchangers. We offer descaling, flushing, and water treatment solutions to protect your investment.
• We install and vent it right: From gas line sizing to proper air supply and venting, we follow code and best practices to keep your system safe and reliable.
• Fast diagnosis, honest fixes: We won’t just swap parts. We find the root cause—whether it’s a flow sensor issue or a poorly placed unit—and solve it for good.

If your tankless water heater is acting up, don’t guess. Call First Chicago Plumbing. We’ll get your system running the way it should—quiet, clean, and constant.

Don’t Let Water Heater Problems Disrupt Your Comfort!

If you’re experiencing issues with your tankless water heater, don’t wait — call First Chicago Plumbing today! Our expert technicians are ready to diagnose and repair your system quickly and effectively, so you can enjoy reliable hot water once again. Whether it’s a minor issue or a major repair, we’ve got you covered with fast, affordable service. Call now at 847-610-6031 or schedule online to get your tankless water heater working like new again!

Tankless Water Heater FAQs

Is a tankless water heater right for me?
It depends on your household’s water usage, plumbing layout, and budget. Tankless units are ideal if:

• You want endless hot water on demand;
• You have limited space and need a compact unit;
• You plan to stay in your home long-term and want energy savings over time;

However, tankless systems work best when professionally sized and installed. If your home has high simultaneous water usage or old plumbing, it may require upgrades. Check out our Is Tankless Water Heater Right For Me article.

What are the benefits of a tankless water heater?
Tankless systems offer several key advantages:

• Endless hot water – great for families or back-to-back showers;
• Energy savings – no standby heat loss like traditional tanks;
• Longer lifespan – up to 20 years with proper maintenance;
• Space-saving design – wall-mounted and compact;
• Cleaner water – no sediment buildup sitting in a tank;

Check out more Tankless water heater benefits.

Can I fix my tankless water heater by myself?
Most of the time, no. Tankless systems rely on sensitive sensors, electronic ignition, and precise water flow control. Common problems—like scaling, flow errors, or ignition failures—require tools and training to diagnose properly.
Trying to fix it yourself can lead to bigger damage or void your warranty.
It’s always better to call a qualified plumber who knows tankless systems inside and out.