Decided to install a boiler? You will not be able to manage his device: you need to provide all the details and elements that will be needed during the installation process. From this article you will learn: why do we need a valve for a storage water heater, what function it has, how to put it.
The need for a safety valve
This part protects the boiler from overpressure. When heated, the water expands, it has nowhere to go, since the tank is an enclosed space. A fuse comes to the rescue, which dumps the excess.
Water will look for a way out in the weak points of the case: gaskets, joints, pipes.
Imagine that the boiler is installed without any obstacle between it and the water supply. When the indicators in the tank exceed the norm, water will flow into the system. As a result, a hot stream can pour out of the taps or from the toilet bowl.
The second important function of the valve is an obstacle to the return flow of water to the line. How is this dangerous? Under reduced pressure (for example, at night), the water from the tank will go into the drain. In this case, the heater will continue to work without liquid and burn. In the worst case, a fire may occur.
Some models provide thermal protection. It turns off the heater when the nominal temperature is exceeded. But if it does not work, damage cannot be avoided.
How the valve works
Let's consider in more detail:
- The part consists of a large and a small cylinder. A large plate-shaped shutter is located; it is triggered by the action of a spring. Small is placed perpendicularly, and its damper works in the other direction. It is also equipped with a drain pipe with a reset handle.
Need to drain the water from the tank? Not a problem. Unplug the device and turn the knob. Content will go down the drain.
- Cold flow enters the system, creating voltage to the valve. The latter opens, starting a stream.
- As the boiler tank is full, the pressure inside increases, so the damper closes.
- During heating, the readings in the housing become even higher. As soon as it exceeds the norm, the spring of the large cylinder is activated, the excess is drained through the drain pipe.
This is the principle of work. Some "masters" believe that it is enough to install a check valve instead of a safety valve. This error can lead to a serious accident.
Boiling liquid builds up pressure in a tank that has no outlet. If you accidentally open the tap at this time, part of the water will drain and the pressure will drop sharply. The remaining water will boil instantly, steam will fill the boiler, which will lead to an explosion. Read what to do if this happens.
We recommend that you follow the installation instructions for the water heater. This will help to avoid sad consequences.
Here are the main functions of the safety valve:
- It blocks the discharge of water into the sewer.
- Regulates system pressure.
- It serves as a protection against water hammer.
- Allows you to quickly drain the contents if necessary.
We will figure out how to install the part yourself.
DIY valve mounting
First you need to choose the right model. If before that you had a water heater installed and you decided to make a replacement, then just take the old part to the store and buy a similar one. For many models of "Ariston", "Electrolux", "Termex" valves are included. But if this is not the case, listen to our recommendations.
- In the photo below are two elements with a forced drain lever. To actuate it, just raise the lever. On the model on the left, the flag is attached with a screw - this eliminates the possibility of an accidental drain. Also on the body is an arrow that indicates the direction of flow. The numbers indicate the pressure the element is designed for. There are no signs on the model on the right, so it is better not to choose this option.
It is important to select the device in accordance with the pressure for which the equipment is designed. Indicators are indicated in the data sheet. Buying a valve without a designation, you take a "pig in a poke."
- Forced reset items are shown below. Pay attention to the union on the left - oblong. It is easier to put on a hose with a clamp on it. Option on the right: fitting short, with extension to the end. It will turn out to put on a hose, but the collar may not fit. On the left there is a cover that allows you to clean the hole from scale and blockage.
On the right is the cheapest Chinese model without signs and cover. It is better to refuse such.
These options are suitable for 50-60 liters devices. For volumes from 200 liters, choose products, as in the photo below.
They have a pressure gauge, tap and attractive design.
Tools and materials
To install you will need:
- adjustable wrench;
- fum tape;
- tow;
- sealed paste.
Work stages
Be sure to unplug the heater. If water has been poured, drain. Installation is carried out on a cold pipeline to the stopcock.
- Cover the threads with tow or fum tape.
- Connect the valve to the nozzle.
- Tighten the connection firmly using an adjustable wrench.
Important! If frequent pressure drops occur in the system, a reduction gear must be installed before the valve.
- A pipe is connected to the nozzle of the part, which leads to the sewer. It’s better to be transparent: that way you can control the process.
To check the performance, just follow the work of the equipment. When heated, water should drip in the tube. If this does not happen, then:
- There was a blockage.
- The device is jammed or malfunctioning.
What can not be done during installation:
- Install stopcocks between the heater body and the fuse.
- Put the fuse at a distance of 2 meters from the equipment.
So you can do the installation work yourself. Installation must be carried out when purchasing a storage boiler.