New Water Heater Requires an Expansion Tank

Posted on January 30, 2020 by Jim Horlander

When installing a new hot water heater, the tank manufactures require an approved expansion tank be installed to maintain the warranty. Heartland Quality Heating and Cooling always installs expansion tanks on replacement water heaters. We do this to protect our customers investment. So why is this an issue with new hot water heaters when you didn’t need an expansion tank in the past? The biggest problem is something called thermal expansion. Thermal expansion happens when you heat water. As the water heats up it expands. There are a few things that have changed in the plumbing world over the past 20+ years that’s created this problem.

Thermal Expansion is the problem

Your water line coming into your home was an open line from the water company. If you had an increase in the water pressure inside your home because of thermal expansion, it would just be passed on to the rest of the area feeding your line. It started to be a concern that water could to be siphoned back into the plumbing system from a contaminated source and contaminate everyone’s water. This is called cross contamination. Local water companies decided that the water line coming into homes should have a safeguard to prevent this, so they started installing one-way valves for the incoming water supply. This eliminated excess pressure build-up from being pushed back out to the main supply. These one-way valves caused water pressure to build inside your plumbing system when thermal expansion occurred, so the water needed some place to expand to. Excessive water pressure can damage water heaters, washers, dish washers, ice makers and any other device connected to the main water supply. Therefore, expansion tanks are now being installed on all new water heater installations and water heater replacements. It’s not just required by the manufactures, it’s also a code requirement and has been for years. It is also recommended that the expansion tanks be tested from time to time; if the tank loses its charge, it no longer protects your plumbing. Make sure that when you’re looking at options for replacing your water heater you also install a thermal expansion tank or test the existing tank, it’s the main safety to protect all your water using devices in your home.

Give Heartland Quality Heating and Cooling a call today. We’ll be happy to replace your water heater the correct way! (816)525-2031