Diaphragm Safety Valves
A diaphragm safety valve is a fixed-set valve that opens via a diaphragm and spring mechanism to relieve excess pressure when the set pressure is reached in closed heating and hot water circuits.
It is used on boilers, combi boilers, calorifiers, solar and closed heating circuits. The product range includes factory-set brass models between 1/2″ and 1 1/4″ × 1 1/2″, from 2.5 bar to 10 bar.
Main Applications
- Central heating boilers
- Combi and wall-hung boilers
- Calorifiers and hot water tanks
- Solar circuits
- Circuits with closed expansion tanks
- Booster sets and pressure tanks
Technical Data
| Type | Diaphragm, fixed-set safety valve |
|---|---|
| Set pressures | 2.5 / 3 / 4 / 5 / 6 / 8 / 9 / 10 bar (product range) |
| Sizes | 1/2″, 1/2″×3/4″, 3/4″, 3/4″×1″, 1″×1 1/4″, 1 1/4″×1 1/2″ (product range) |
| Body | Brass (product information) |
| Connection | Male or female inlet, female outlet (depending on model) |
| Setting | Fixed at the factory; not changed on site |
| Fluid | Water (heating and domestic) |
| Temperature | Depending on model |
Material Options
| Part | Heating circuit type | Domestic water / calorifier type |
|---|---|---|
| Body | Brass | Brass |
| Set range | Low pressure (e.g. 2.5 – 3 bar) | Higher (e.g. 6 – 10 bar) |
| Relief | Diaphragm + spring | Diaphragm + spring |
| Typical use | Boilers and combi boilers | Calorifiers, solar |
Which material? The set pressure of a safety valve must not exceed the maximum allowable working pressure of the protected boiler or tank. Set pressures and sizes are taken from product names; the temperature limit is verified for the chosen valve.
Advantages
Safe Relief
- Discharges overpressure
Factory Set
- No wrong-setting risk
Compact
- Suits boiler tops
Wide Choice
- 2.5 – 10 bar
Construction and Design Features
- Brass body
- Diaphragm and spring
- Discharge outlet
- Test cap (depending on model)
Send the set pressure, inlet-outlet size and circuit type; we will confirm a suitable diaphragm safety valve from stock.
How to Choose?
- Choose the sizeDetermine the inlet and outlet thread size.
- Determine the set pressureChoose by the boiler or tank maximum pressure.
- Fluid and temperatureState heating or domestic water.
- Check the capacityConfirm relief capacity suits boiler output.
Complementary Products
Why ORFA?
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