subject: Basics About Hydronic Circulator Pumps [print this page] Hydronic circulator pumps are commonly used in closed hot water home heating systems. Hydronic circulator pumps circulate the hot water through the heating system and work in conjunction with the boiler, hydronic zone valves and thermostats to heat/cool your home.
Hydronic circulator pumps that are used inside the home are usually small in size and are powered with the help of electricity. These are constructed from cast iron and are installed near boiler in series with the hot water piping.
Hydronic circulator pumps are found to be sealed and contain an internal motor, bearings and impeller that reduce its leaking and breakdown. You will find these pumps in series with the boiler, hydronic zone valve and hot water heating.
When the thermostat indicates that heat is required, the zone valve is opened, the circulating pump is activated and hot water is circulated through the hot water heating system. As the water cools the boiler turns on and reheats the water in the closed loop hot water heating system.
Besides being used for home heating systems, a hydronic circulator pump is also frequently used for supplying on-demand hot water for the home's domestic hot water needs. The circulator pump continuously provides hot water through the home hot water supply lines so that when a hot water faucet is turned on, hot water is immediately available. The advantage of this is that water is not wasted but the disadvantage is that you waste energy by constantly heating water that may be rarely used.
If you consider using a circulator pump for your home's hot water system, then you may want to insulate your hot water supply pipes or put the system on a timer so that you mitigate the waste of energy.
The performance of a circulator pump can be calculated using its flow performance. The flow performance basically can be determined by the flow-rate (number of gallons/liters of water that can be pushed through the system per minute) and the circulator pumps head pressure.
A circulator pumps head pressure rating is the maximum vertical height the pump can lift the water. Consequently, if you have a large hot water system design that needs to go up two floor levels (e.g. from the basement to the second floor of a home), you will need a circulator pump that can support a higher flow performance with a high head pressure.
