Expansion tanks are required in a closed loop heating or chilled water HVAC system to absorb the expanding fluid and limit the pressure within a heating or cooling system.
What is the purpose of an expansion tank?
Its purpose is to deal with thermal expansion of water as it heats up in the water heater – to prevent water pressure from getting too high. If water pressure gets high enough it can damage valves in plumbing fixtures, joints in supply pipes and even the water heater.
What is the purpose of an expansion tank in a close cooling system?
The expansion tank absorbs excess coolant and minimizes excess pressure in the engine cooling system . An expansion tank helps maintain a minimal pressure increase during heated water expansion, helps reduce coolant hammer, and helps protect the engine cooling system from stress.
What is closed expansion tank?
An expansion tank or expansion vessel is a small tank used to protect closed (not open to atmospheric pressure) water heating systems and domestic hot water systems from excessive pressure.
How does a closed expansion tank work?
Expansion tanks work by equalizing pressure throughout the system . An expansion tank is a small tank divided in two sections by a rubber diaphragm. ... As pressure increases, the diaphragm in the expansion tank is pushed down. This compresses the air in the tank, creating more space for excess water to enter.
How do I know if I need a new expansion tank?
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).
Does the expansion tank go on the hot or cold side?
Although expansion tanks can be installed on the hot side , we strongly recommend they be installed on the cold line, downstream of the shutoff valve.
What is the difference between an expansion tank and a pressure tank?
The most significant difference between expansion and pressure tanks is their functionality . An expansion tank handles water expansion and provides protection for water valves and heaters. On the other side, the pressure tank lengthens the lifespan of the pump.
What pressure should my expansion tank be set at?
The recommended water pressure is between 50 and 60 PSI . Thermal Expansion Tanks contain an air bladder which is pressurized with air, and expands and contracts to absorb the expanded water from the water heater. needed. Check the air pressure in the Expansion Tank using a tire gauge.
Do you need a coolant expansion tank?
When the radiator is high enough to act as a fill point and pressure relief an expansion tank is not necessarily required . In those applications a recovery style tank may be used instead. Liquid cooled systems are pressurized in order to raise the boiling point of the coolant.
What happens if expansion tank pressure is too high?
If the psi is too high, you can simply let some air out by pressing down on the valve until enough air has escaped . If the psi is too low, you’ll need to add some air with a tire pump. We highly recommend using a hand pump instead of an air compressor when adding air. An air compressor could easily rupture the bladder.
What happens if expansion tank is full?
It is a one-way system. Once the water gets into the expansion tank it does not flow back into main hot water tank . If you have a closed-vent boiler based system, occasionally the expansion tank will need to be drained of water to be recharged for future effective over-flow use.
Can you install expansion tank upside down?
Expansion tanks can be installed in any direction . Whether oriented uprightly, horizontally, or even upside down, the expansion tank will function properly without any adverse effects. When putting an expansion in an abnormal position (specifically sideways or horizontally), make sure to support the tank.
What happens when an expansion tank fails?
Oftenthe diaphragm dividing the two systems will fail , causing the two systems to become one. When this happens, the expansion tank turns into a “dead leg” that will eventually cause damage and premature failure to your water heater.
How often should expansion tank be replaced?
Between five and 10 years is the average lifespan of your tank. If your home’s water pressure matches the air pressure in your expansion tank, you can extend the life of your tank. You’ll need to replace it in some cases.
