Manual Valves
There are a number of manual valves required for the system to operate properly and safely. These valves are used as shut off valves, drain valves and throttling valves. They can be globe, gate, ball or balancing type valves.
The globe valve can be used as a shut off, drain or throttling valve. Even in the open position, the valve is fairly restrictive to flow. It has a much greater equivalent length (resistance) than the other types of valves.
The gate valve can be used as a shut off or drain valve. When in the open position, there is very little resistance to flow. Gate valves have a greater susceptibility to chatter (noise) and
malfunction with age. Gate valves tend to be less expensive than the other type of valves.
The ball valve can be used as a shut off or drain valve but not a throttling (balancing) valve. When in the open position, a full bore ball valve has very little resistance to flow, and these valves tend to be both the least expensive and the least susceptible to seizing over time. Do not use reduced bore ball valves as they are very restrictive to water flow.
The balancing valve can be used as a throttling valve. It can make small flow changes easily and has lower resistance than a globe valve. This valve will be considerable more expensive.
Balance Valve
Ball Valve
Globe Valve
Gate Valve
7
