Table of Contents
What is a potable water expansion tank?
What Is an Expansion Tank? An expansion tank is designed to relieve pressure in both potable water and closed hydronic heating systems. It ensures that constant pressure is maintained within the pipes so they do not get damaged from excess pressure.
Do I need an expansion tank on my water heater?
If your home has a “closed” plumbing system, then yes, you’ll need an expansion tank. You see, homes have either an open or a closed plumbing system. A closed plumbing system prevents water from flowing in the reverse direction (i.e., water won’t flow back into city lines once it enters your home’s pipes).
Why is the potable water expansion tank useful?
The expansion tank is designed to handle the thermal expansion of water as it heats up in the water heater, preventing excessive water pressure. If water pressure gets to high it can damage valves in plumbing fixtures, joints in supply pipes and the water heater itself.
What size expansion tank do I need for a 55 gallon water heater?
General Guidelines for Sizing an Expansion Tank
| Water Heater Capacity | Supply Pressure (psi) | Expansion Tank Size |
|---|---|---|
| 40 to 60-gallon | 40-50 psi | 2-gallon |
| 40 to 60-gallon | 60-80 psi | 3.2-gallon |
| 80-gallon | 40 psi | 2-gallon |
| 80-gallon | 50-60 psi | 3.2-gallon |
How far can an expansion tank be from a water heater?
The items which should be installed in sequence in the cold water line are (1) the EXPANSION TANK must be installed at least 18 inches away from the cold water inlet fitting on the water heater, (2) the PRESSURE GAUGE, and (3) the PRESSURE REDUCING VALVE, if required, see Figure 1.
Can you use a potable water expansion vessel on a heating system?
Yes, it is: the expansion vessels suitable for potable water applications can be installed on central heating systems.
Where is the best place to install an expansion tank?
Your expansion tank can be anywhere on your plumbing system and does not need to be installed in close proximity to the water heater. It is most commonly installed using a “T” at the cold inlet to the water heater. But, functionally, it can be installed anywhere on the cold inlet line.