## Water Heater Supply Line Sizes
The size of water heater supply lines depends on several factors, including the size of the water heater, the flow rate of the water, and the length of the run. In general, larger water heaters require larger supply lines, and longer runs require larger supply lines.
The following table shows the recommended water heater supply line sizes for different size water heaters and flow rates with the assumption that the total length of the run is less than 50 feet:
| Water Heater Size | Flow Rate | Supply Line Size |
|—|—|—|
| 30 gallons | 60 GPM | 3/4 inch |
| 40 gallons | 80 GPM | 1 inch |
| 50 gallons | 100 GPM | 1 inch |
| 60 gallons | 120 GPM | 1-1/4 inch |
| 80 gallons | 140 GPM | 1-1/4 inch |
If the run is longer than 50 feet, you may need to increase the supply line size. For example, if you have a 40-gallon water heater and the run is 75 feet, you would need to use a 1-1/4 inch supply line.
Note: It is always best to consult with a licensed plumber to determine the correct size water heater supply lines for your specific application.
## Materials for Water Heater Supply Lines
Water heater supply lines can be made from a variety of materials, including copper, PEX, and CPVC.
Copper is a durable and corrosion-resistant material that is often used for water heater supply lines. However, copper is also more expensive than other materials.
PEX (cross-linked polyethylene) is a flexible and easy-to-install material that is becoming increasingly popular for water heater supply lines. PEX is also resistant to corrosion and freezing.
CPVC (chlorinated polyvinyl chloride) is a rigid material that is less expensive than copper or PEX. However, CPVC is not as durable as copper or PEX and is more susceptible to damage from freezing.
## Installing Water Heater Supply Lines
Installing water heater supply lines is a relatively straightforward process. However, it is important to follow the manufacturer’s instructions carefully.
1. Turn off the water supply to the water heater.
2. Disconnect the old supply lines.
3. Install the new supply lines.
4. Turn on the water supply to the water heater.
5. Check for leaks.
## Tips for Installing Water Heater Supply Lines
Use a pipe wrench to tighten the fittings.
Apply a sealant to the threads of the fittings.
Support the supply lines with pipe clamps.
Insulate the supply lines if they will be exposed to cold temperatures.
## Conclusion
The size of water heater supply lines depends on several factors, including the size of the water heater, the flow rate of the water, and the length of the run. It is important to use the correct size supply lines to ensure that your water heater is able to provide adequate hot water.