Installing a new water heater in your Sacramento, CA home could prove more involved than you think. When homes have closed plumbing systems, their water heaters require expansion tanks. These small, secondary tanks account for the thermal expansion that water undergoes as its temperature rises. Expansion tanks prevent excess pressure within the water heaters themselves, limit wear and tear, and minimize the risk of tank ruptures. Read on to find out more.
What Is a Closed Plumbing System?
Also known as a closed loop system, a closed plumbing system prevents water from flowing in the opposite direction. When fresh, potable water enters your pipes from the municipal water supply, there’s only one way for it to get out. As soon as it enters your home’s pipes, this water must flow out of your taps and exit through your drains. It might also pass through your water heater, dishwasher, or washing machine, but it will never return the way it came.
Open loop plumbing systems or open plumbing systems tend to be a bit cheaper to set up, but they’re also a lot less efficient. The water that flows into your building from the municipal supply is water that you’ll be billed for whether you use it or not. With an open loop system, excess or unused water can always reverse its direction and move back into the supply pipes. However, a good portion of this liquid will likely evaporate before you turn your water back on. Even when evaporation in an open loop system is nominal, the cumulative effect on a home’s water bill can be substantial over time. For this and other reasons, most properties have closed-loop systems.
How Does Having a Closed Loop System Affect Your Water Heater?
Your water heater tank is constantly filled to capacity. This way, everyone in your home will have access to the hot water they need when they need it. The maximum fill capacity of water heaters accounts for some measure of thermal expansion. When heated, water can expand by as much as 4% as it nears its boiling point. Without somewhere to go, warm water would place a full water heater under a significant amount of stress. This excess pressure would wear this appliance down at a rapid rate, and it could lead to tank ruptures or other dangerous events.
An expansion tank provides a separate, secondary reservoir for water to go when thermal expansion exceeds a water heater tank’s limitations. As air and water are displaced, pressure levels within water heaters remain moderate and no undue stress is applied. Having an expansion tank doesn’t mean that you’ll have more hot water for baths or showers. However, it does mean that your water heater will likely enjoy a full and ultimately problem-free lifespan.
Cold Weather Matters, Too
If your power goes off and your water heater can no longer function, there’s also the risk of freezing conditions causing in-tank water expansion. Although this is less of a risk in Sacramento, it’s important to note that water heater expansion tanks have a cold-weather purpose too. Whenever stored water becomes exceedingly hot or exceedingly cold, there’s always the potential of having it expand beyond the capacity of its containment unit.
How to Know If Your Home’s Plumbing System Is Closed
California Plumbing Code Section 608.3 requires all homes with closed-loop plumbing systems to have expansion tanks installed on their water heaters. Installing a water heater in your home without one will keep this appliance from passing essential permitting inspections. California also requires all water heater installations to be permitted. This is a good reason to avoid trying to tackle water heater replacement on your own even if you have a moderate amount of plumbing experience. We can make sure that both your water heater and its expansion tank are sized and installed correctly and that all necessary permits are pulled.
With efficiency being a top goal of California legislators and many California counties regularly experiencing drought conditions, you aren’t likely to find homes in the state that have open-loop plumbing systems. Open-loop plumbing systems simply create too much water waste to be worth the limited benefits they supply. It’s far more expedient for homeowners to have closed-loop systems and expansion tanks as well as any other mitigation strategies that are needed throughout their plumbing systems. Odds are good that your Sacramento home has a closed plumbing system and a water heater that requires an expansion tank.
If you’re still unsure as to whether or not your plumbing system is closed, you can look for a backflow prevention device. This is an installed component that prevents the backflow of water at the main water supply. This could be a recirculating pump with a check valve, a standard pressure-reducing valve (PRV), or any other similarly functioning unit. When we provide any plumbing service at your home, we can also verify whether or not your plumbing system is an open-loop or closed-loop system. While there’s often confusion with older, historic properties, we find that most modern buildings in the region are built with closed-loop systems.
Why Expansion Tanks Aren’t Necessary in Open-Loop Plumbing Systems
In an open-loop plumbing system, water can flow in both directions. Not only is there no shut-off that keeps unused water from moving back into your city or county’s municipal water supply, but there’s also nothing that stops water in appliances like water heaters from exiting when excess pressure forces them to. Thus, even when a water heater tank is at full capacity, the water that it holds could expand by as much as 4% without causing undue stress or danger. Instead of rolling over into a connected expansion tank, excess water can backflow into the same pipes that it recently exited from.
How Often Do Expansion Tanks Need to Be Replaced?
Traditional tank-based water heaters can last between 10 and 15 years with proper maintenance. If your home has excessively hard water or other water quality concerns, you might need to replace this appliance once every 10 to 12 years instead.
Thermal expansion tanks tend to have significantly shorter lifespans. Most models must be replaced once every five to eight years. When you install a new water heater, you should have a new thermal expansion tank installed as well even if your old one doesn’t seem to have any significant wear. You’ll also need to replace this unit again at your water heater’s half-life. Fortunately, thermal expansion tanks are among the many features that we check when performing whole-house plumbing inspections. During these visits, we can look for small and developing issues throughout your entire plumbing and water heating system, and we can catch and correct problems before they result in physical harm or property damage.
We’ve been serving residents of Sacramento, CA and the surrounding area for more than 30 years. We offer plumbing, furnace, air conditioner, and heat pump service. We also provide HVAC services, water heaters, and indoor air quality solutions. Get in touch with Gallagher's Plumbing, Heating and Air Conditioning today to find out more about water heater expansion tanks or to schedule an appointment.