how to install hot water

Ever stepped into a freezing shower on a winter morning? The discomfort is a stark reminder that hot water is more than just a luxury; it’s a necessity for comfortable living, hygiene, and even crucial household tasks. From dishwashing to laundry, and of course, those essential showers, a reliable source of hot water significantly improves our quality of life. But what happens when your old water heater gives out, or you’re building a new home and need to install a system from scratch? Tackling the installation yourself can save you a considerable amount of money, granting you control over the process and ensuring the job is done right, according to your specifications.

Installing a hot water system can seem daunting, but with the right guidance and preparation, it’s a manageable DIY project for many homeowners. Understanding the different types of water heaters, preparing the installation site, and safely connecting the plumbing and electrical components are all critical steps. Incorrect installation can lead to leaks, electrical hazards, and even void warranties, so taking the time to learn the proper techniques is essential. This guide provides a comprehensive overview of the installation process, helping you navigate each stage with confidence.

What kind of water heater do I need, and how do I install it safely?

What size hot water tank do I need?

The ideal hot water tank size depends primarily on the number of people in your household and your typical hot water usage. A general guideline is 40-50 gallons for 1-2 people, 50-60 gallons for 3-4 people, and 60-80 gallons or larger for households with 5 or more people. Consider your peak usage times, such as morning showers or simultaneous appliance use, when making your decision.

To accurately determine your needs, estimate your daily hot water consumption. Dishwashers use around 6 gallons per cycle, washing machines use 20-40 gallons per load, and showers typically use 2-3 gallons per minute. Factor in things like filling large bathtubs or frequently running hot water for other purposes. If you regularly run out of hot water, or if you are planning to expand your family, consider sizing up to the next larger tank. Finally, think about the type of water heater you are considering. Tankless water heaters, for example, provide hot water on demand and eliminate the need for a storage tank, but their flow rate must meet your peak demand. Hybrid heat pump water heaters, while very efficient, may have specific size recommendations based on your climate and usage patterns. Consulting with a qualified plumber can provide a more precise recommendation tailored to your specific circumstances and help you avoid undersizing or oversizing your new hot water tank.

How do I connect the water lines to the new heater?

Connecting the water lines to your new water heater involves carefully attaching the cold water inlet and hot water outlet pipes, ensuring proper fittings and watertight seals. Always begin by shutting off the main water supply and draining any remaining water from the old tank. Use pipe wrenches to tighten fittings securely, and be mindful of using Teflon tape or pipe dope on threaded connections to prevent leaks.

The cold water inlet is typically located on the right side of the water heater and is often marked with blue. The hot water outlet is usually on the left and marked with red. Before connecting, ensure both nipples extending from the tank are in good condition. If they show signs of corrosion or damage, replace them. When connecting the pipes, ensure proper alignment to avoid cross-threading. Start tightening the fittings by hand before using pipe wrenches, and avoid overtightening, which can damage the connections.

After making the connections, slowly turn the main water supply back on, and carefully inspect all joints for leaks. If you notice any leaks, immediately shut off the water supply and tighten the connections further. If leaks persist, you may need to disassemble the connection, apply fresh Teflon tape or pipe dope, and reassemble. Consider having a professional plumber inspect your work to ensure proper installation and avoid potential water damage. Once you’re confident that there are no leaks, insulate the hot water pipe to minimize heat loss.

What’s the best type of pipe for hot water lines?

PEX (cross-linked polyethylene) is generally considered the best overall type of pipe for hot water lines in residential plumbing due to its flexibility, ease of installation, resistance to corrosion and scaling, and ability to withstand high temperatures and pressures. While copper has been a traditional choice, PEX offers significant advantages in cost, installation time, and long-term durability for most home applications.

PEX’s flexibility allows it to bend around corners and obstacles, reducing the number of fittings needed, which minimizes potential leak points. This flexibility also makes it more resistant to freezing and bursting compared to rigid pipes like copper. The cross-linked polyethylene material is highly resistant to corrosion, scaling, and chlorine degradation, ensuring a longer lifespan and maintaining water quality over time. PEX is also more energy-efficient than copper, as it loses less heat along the pipe run, resulting in slightly hotter water at the tap and lower energy bills. While copper is still a viable option, especially for exposed plumbing where aesthetics are a concern, it’s more expensive than PEX and requires soldering, a skill that requires training and practice. CPVC (chlorinated polyvinyl chloride) is another option, known for its rigidity and high-temperature resistance. However, CPVC can become brittle over time, especially with exposure to UV light, and requires specialized glue and fittings. Therefore, for a balance of cost, durability, ease of installation, and performance, PEX remains the superior choice for most hot water line installations in residential settings.