Hydrofor systems are designed to operate within a specific pressure range to respond to variable flow demands when the mains pressure is insufficient. The pressure switch (pressostat) in these systems controls the pump’s start and stop pressures. Incorrect pressure settings can reduce pump performance and shorten the lifespan of system components.
When adjusting hydrofor pressure, factors such as the pump characteristic curve, tank volume, and application type (e.g., domestic systems, commercial buildings, irrigation systems, etc.) must be considered. In this article, we will focus on how to properly set the pressure in domestic (household) hydrofor systems from a technical perspective.
What is Hydrofor Pressure?
Hydrofor pressure is the pressure generated when water is delivered through a hydrofor system to the network or faucets. This pressure ensures that water flows properly through the home plumbing system and reaches all usable areas, even in challenging conditions such as high-rise buildings. Hydrofor systems increase water pressure, allowing water to be transported over longer distances and to higher floors.
Hydrofor pressure must remain within specific limits. Too low pressure can result in insufficient flow or weak water output from faucets. Conversely, excessively high pressure can damage the plumbing, cause leaks at pipe connections, or break faucet heads. Therefore, hydrofor systems are designed to maintain efficient and safe pressure levels, ensuring reliable water supply while also optimizing energy use.
Why is Hydrofor Pressure Adjustment Important?
- Low pressure: Water does not reach faucets with adequate speed, causing discomfort.
- High pressure: Can damage pipes, fittings, and devices, and increase unnecessary energy consumption.
Proper pressure adjustment ensures that the system operates efficiently and safely. This balance guarantees both comfortable water use and the long life of the plumbing system.
How to Adjust Hydrofor Pressure?
Hydrofor pressure adjustment is critical for efficient system operation and is typically done via the pressostat (pressure switch) on the hydrofor. The pressostat continuously monitors water pressure and ensures the system operates within a specific range. It sets the lower and upper pressure limits for when the hydrofor starts and stops.
The pressostat ensures that the system maintains adequate water flow and pressure. It prevents low pressure from causing insufficient flow and high pressure from damaging the plumbing. Additionally, the pressostat helps optimize energy consumption, avoiding unnecessary costs. Proper adjustment of the pressure switch contributes to a longer lifespan for the hydrofor system and more efficient water use.
How to Adjust the Pressostat
Adjusting the pressostat is an essential step for correct hydrofor operation. Typically, there are two main screws on the pressostat: the start (or ON) screw and the stop (or OFF) screw. These screws set the pressure levels for starting and stopping the pump.
- Start screw: Determines when the hydrofor starts as water pressure reaches a specific level. This ensures water begins flowing through the pump at the correct lower pressure.
- Stop screw: Determines when the hydrofor stops as water pressure reaches a specific upper level. This prevents the system from exceeding safe pressure limits and protects the plumbing and pump.
Both screws must be adjusted carefully. Incorrect settings can lead to insufficient pressure or excessive pressure that damages the system. Adjustments should follow the manufacturer's recommended pressure values and be checked regularly for optimal performance and long-term reliability.
Typical Pressostat Screws
- Pressure Range Adjustment Screw (P): Sets the lower pressure. Turning clockwise increases both lower and upper pressure.
- Differential (ΔP) Adjustment Screw: Sets the difference between upper and lower pressure. Turning clockwise increases only the upper pressure while keeping the lower pressure constant.
Example:
- Lower pressure: 2 bar
- Upper pressure: 3.5 bar
In this case, the hydrofor starts when pressure drops below 2 bar and stops when it reaches 3.5 bar.
Pressure Adjustment in Domestic Hydrofor Systems
For domestic hydrofor systems, the typical steps are:
- Read the system pressure from the manometer when the pump is off.
- Check the tank air pressure. It should usually be 0.2 bar below the system’s lower pressure (e.g., if lower system pressure is 2 bar, tank air should be 1.8 bar).
- Make adjustments using the pressostat screws.
Note: When checking tank air pressure, the system must be fully depressurized and the hydrofor turned off.
Important Notes for Masdaf Hydrofors
Pressostats in Masdaf hydrofors are factory-set; user adjustments are not recommended. Any malfunction should be addressed by an authorized service. Pressure adjustments should be based on the pump characteristic curve and should not go below the pump’s minimum allowed pressure.