First understand the several functions of the expansion tank:
Role one
Expansion tank
Related to the thermal expansion and contraction of water in the system...
It is well known that the volume of water will expand and expand...
The volume will be reduced by the cold volume...
That problem is coming...
Where is the system punching bag at this time?
If the water expands like this, it won’t swell the water pipe.
Because the volume of the entire closed system water is constant
The expansion tank is the outlet cylinder
The volume of water has expanded
Excess water will overflow through the expansion tank...
Reduced volume of expansion tank backup water source
The water will be automatically replenished by the gravity of the water...
Role two
The expansion tank also has the function of replenishing the system and stabilizing the system pressure.
If the system leaks or repairs, the water volume is partially reduced.
The expansion tank is the best automatic water supply device...
The expansion tank is generally placed at a higher point than the highest point of the system.
The change in water level is basically negligible
So it has the function of stabilizing the pressure of the entire system.
The installation height of the expansion tank should be at least higher than the system
The highest point is 0.5m (usually 1.0 to 1.5m)
Role three
The expansion tank acts as the highest point of the system and is in direct communication with the atmosphere
Therefore, the expansion tank also has a certain system exhaust function.
The water pipes of the expansion tank are generally connected to
System return pipe or water collector
That is, the water inlet of the pump
Volume calculation formula
For ordinary high-rise civil buildings
If based on the system design cooling load Qo
The unit water capacity of the system is approximately 2 to 3 liters / kW
How many kilowatts is the cooling capacity of the mainframe?
Just put it in this way
When using a dual control system
If the minimum working temperature for taking water is 7 °C,
Maximum operating temperature is 65 ° C
The effective expansion volume V of the expansion tank,
A simplified estimation method can be used to calculate:
V=0.006×(65-7)×(2～3)Qo=(0.07～0.1)Qo (liter)