Tired of running out of hot water because your tank is too small for your needs? Now is a great time to consider upgrading to a tankless unit.

As a local, family-owned business, we never use subcontractors—just our own highly trained team who ensures every installation meets our high standards.

Monkey Wrench Plumbing, Heating, Air & Electric can help you select the right equipment for your needs and provide a seamless tankless water heater installation in Los Angeles or nearby communities.

Tankless Water Heater Replacement Pricing


A neutralizer is a canister filled with media that’s installed on condensing tankless water heaters to neutralize acidic condensation before it drains out. This helps protect concrete, landscaping, and drain/sewer lines from damage, and it can also reduce algae buildup near the unit. In Los Angeles County, it’s commonly required for environmental compliance. Most neutralizers last around 2–3 years. Without one, acidic water can corrode pipes, stain surfaces, harm plant life, and even create slick conditions near the drain area.


A recirculation pump helps deliver hot water faster at sinks and showers by cycling water through the plumbing system—either continuously or on-demand—so you don’t have to wait as long and you can cut down on water waste. Replacements typically take 1–4 hours depending on the home and setup. Pricing varies based on whether you have a dedicated return line or a retrofit that uses the cold line, how accessible the water heater is, the type of pump (timer, demand, or sensor-based), whether hard water filtration is recommended, and if any electrical work is needed.

One quick note: with retrofit systems that use the cold line as a return path, the cold tap may run slightly warm at first. Dedicated return lines avoid that, and many systems use sensors or bypass valves to help keep the cold line cold.


Heat exchanger replacement is needed when the internal component that heats water becomes clogged with scale or fails due to age, hard water, or missed maintenance. Since the heat exchanger is the core of the tankless unit, problems here can lead to inconsistent hot water—or no hot water at all. The job typically takes 2–4 hours, but the final cost depends on the unit make/model, parts availability, whether the part is covered under warranty, how severe the scale or corrosion is, and how accessible the unit is. Regular maintenance can extend the life of the heat exchanger and help keep warranty options open.