Home Improvement

What is an alarm check valve?

The alarm check valve is a water flow alarm device designed for vertical installation in the main supply to a wet pipe sprinkler system. When a flow of water from the system equals or exceeds that of a single sprinkler, the valve is to actuate a fire alarm.

Where is the alarm check valve located in a sprinkler system?

As such, this valve is typically located at the fire sprinkler system riser.

Which valve is used in sprinkler system?

Outside stem and yoke valve.

Will a check valve stop a fire?

A check valve can only prevent the reverse gas flow. However, a Flash Back Arrestor prevents reverse gas flow AND arrests the flashback. A check valve cannot arrest a flash back. This could allow the flame to get past the torch and into the hoses.

How does a water flow alarm work?

When water moves past the flow switch in the pipe the pressure of the water moves an integrated paddle (a component of the flow switch) in the direction of water flow. This movement activates a switch that triggers an alarm signal at a fire detection and alarm system.

When should an alarm check valve be used?

We use an alarm check valve on the riser to lock water pressure into the system and prevent the water in the sprinkler piping from traveling back into the water supply. Trim piping around the check valve is used to activate an alarm, which can be a mechanical or electrical device, during a water flow condition.

What does a check valve do in a fire sprinkler system?

Pressure-activated check valves prevent contamination and flooding from water sources used in fire protection systems. A check valve is a device that permits the flow of semisolids, liquids, or gases in only one direction.

What is a sprinkler alarm valve?

A sprinkler alarm valve, or fire sprinkler valve, prevents a reverse flow of water from the installation into the fire-pump room, but in case a fire sprinkler is activated (opened) due to fire, the sprinkler alarm valve will open and permit water flow into the system.

What is an OS and Y valve?

OS&Y means “outside stem and yoke” or “outside screw and yoke”. OS&Y gate valves operate by opening and closing via a gate, which lowers into or rises out of the valve. Raising the gate allows water to flow through the valve while lowering the gate cuts off the water flowing through the valve.

Where is the main sprinkler system valve usually installed?

In newer lawn irrigation systems, the valves should be installed in valve boxes set into the earth. Often these are easily visible. In small yards, there is often a single valve box located near where the irrigation pipes enter the ground from the water source.

Where are water flow detectors located?

For optimal performance, water flow detectors should be mounted in an area where there is adequate room to service the device and it will not be damaged by normal nearby activity. Other general installation rules include: The flow switch should be mounted six to seven feet above the ground.

Where should a flow switch be installed?

The flow switch should be located in a horizontal section of pipe where there is a straight horizontal run of at least 5 pipe diameters on each side of the flo w switch. The flow switch may be installed in a vertical pipe if the flow is in the upward direction.

Does a dry sprinkler system have a flow switch?

This allows water to fill the system piping and discharge through open sprinklers. The water also fills the alarm line piping activating the waterflow pressure switch (B). Note that dry systems must utilize pressure type flow switches.

How do you tell if a sprinkler system is wet or dry?

Water is immediately dispensed out and flowing a dry sprinkler system the piping system is filled with air or nitrogen. When the sprinkler operates. You'll have a delay of water.

At what temperature does a fire sprinkler activation?

between 155 to 165 degrees Fahrenheit

Fire sprinkler systems are actually quite sophisticated, and are designed to be heat sensitive so that sprinklers only activate when the temperatures rise to fire-induced temps, usually somewhere between 155 to 165 degrees Fahrenheit.

Is a pressure switch the same as a flow switch?

The basics of pressure switches

Some pressure switches, also known as pressure-type flow switches, activate when water flows through dry-pipe, preaction, and deluge systems.

Is a flow switch a sensor?

A flow switch, sometimes referred to as a flow sensor or flow indicator, is a device used to monitor the flow rate and pressure of liquids, air or other gaseous media through a duct, system or loop.

What is a potter switch?

The Potter PS10 Series Pressure Actuated Switches are designed for the detection of a waterflow condition in automatic fire sprinkler systems of particular designs such as wet pipe systems with alarm check valves, dry pipe, preaction, or deluge valves.

Is a flow switch normally open or closed?

Flow switches are either configured to be Normally Open (NO) or Normally Closed (NC). This refers to the default state of the switch. With a NO switch, the circuit is open (OFF) until triggered otherwise. With a NC switch, the circuit is closed (ON) until triggered otherwise.

What is the difference between normally closed and normally open?

Normally open – Is a contact that does not flow current in its normal state. Energizing it and switching it on will close the contact, causing it to allow current flow. Normally closed – Is a contact that flows current in its normal state.

What is NC switch?

A normally closed switch or contact is an electrical switch that allows current to flow through it in its normal state (when it is not compressed or activated). Normally closed switch.

What is the purpose of a flow switch?

Flow switches might be used to monitor the flow rate of a liquid, trigger an alarm if the flow is too high or too low or even protect a pump. The flow sensor will usually send an electrical signal to a PLC or other electronic controller.

How many types of flow switches are there?


There are two main flow switch types — the paddle design and the piston or shuttle design. The paddle design of a flow switch places a hinged or spring-mounted paddle in the liquid flow path. Media flowing at the target rate holds this in position.

How much current does a flow switch?

Product Specification

Usage/Application water flow control
Brand broiltech
Switching Current 2 amp
Operating Pressure upto 10 bar
Flow Media Type Liquid

What is a flow switch and how does it work?

Next we have the piston or shuttle design flow switch with a piston type flow switch a free-floating magnetic piston responds to the amount of flow within the line when there's an increase or decrease

How do you reset a flow switch?

Turn the unit off and unplug it from the power source for 30 seconds. This resets the spa’s control panel and will make the switch work again. If this does not work, turn the unit off again before trying any other troubleshooting techniques.

Which sensor can be used to stop the flow of a liquid into a pipe by means of an electric current?

A cost-effective and most commonly used water flow sensor is Paddlewheel sensor. It can be used with water-like fluids.