A gravity-fed water system utilizes the force of gravity to distribute water throughout a building, relying on the height of a storage tank to create water pressure. These systems are commonly found in older homes and are known for their simplicity.
Key Components and Function
A gravity-fed system is identified by two main components:
- Cold Water Storage Tank: Typically located in the loft or attic, this tank stores the cold water supply.
- Hot Water Cylinder: Usually found in an airing cupboard, this cylinder heats and stores hot water.
The key to a gravity-fed system is the principle that water flows from a higher point to a lower point due to gravity. This means that the height of the cold-water storage tank determines the water pressure throughout the system. The higher the tank, the greater the water pressure delivered to the taps and fixtures below.
How the System Operates:
- Cold Water Supply: Mains water enters the cold water storage tank.
- Gravity Distribution: Gravity pulls the water down from the cold water storage tank through pipes to the various cold-water outlets in the building, such as taps and toilets.
- Hot Water Production: To generate hot water, cold water from the storage tank flows into the hot water cylinder, where it is heated, usually by an immersion heater or a central heating boiler.
- Hot Water Distribution: Hot water, now at a higher point than the outlets, is then distributed through pipes to hot water taps due to gravity.
Pressure Considerations
The effectiveness of a gravity-fed system relies entirely on the vertical distance between the cold-water tank and the outlets. This height difference dictates the water pressure. Low pressure can sometimes be an issue with these systems, especially if the tank is not high enough or the demand is higher (multiple users at once).
Advantages and Disadvantages
| Feature | Advantages | Disadvantages |
|---|---|---|
| Simplicity | Basic design with few mechanical components, leading to higher reliability. | Dependent on a higher storage tank, which may not be suitable for all buildings. |
| Reliability | Less prone to breakdowns due to the basic mechanical structure. | Tend to have low water pressure, particularly in multi-story buildings. |
| Cost | Generally cheaper to install. | Requires a large amount of space for tanks. |
Practical Insights:
- Low Water Pressure: To improve low pressure, consider increasing the height of the cold-water storage tank (if feasible) or installing a shower pump to boost the water pressure to specific outlets.
- Maintenance: Regularly check the tank for leaks and debris, to ensure optimal system performance.
- Water Storage: Large tanks ensure a good water reserve in case of disruptions to the mains supply.
