Selecting the valve
If the water heater valve is dripping, a crack is found on its body, the discharge valve leaks, or the device is missing from the water heater kit, it is necessary to properly select new equipment.
The main parameters considered in the selection are:
- the diameter of the nozzles and the threads. The device is selected according to the size of the supply pipes and fittings of the heater.
Standard sizes 1/2, 3/4, 1 1/2 and so on. If the diameter or thread will not match the mains and the boiler, you will need to install additional adapters, which will reduce the tightness of the system;
- ultimate pressure. This parameter depends on the power and model of the water heater and is specified in the accompanying documentation. The nominal pressure is usually indicated directly on the body of the equipment.
Types of safety relief valves
Check valves can be triggered in any situation. The work can be carried out both in normal cases and in the event of an emergency.
They can be divided into the following types:
The first type of valve has a special shutter in the form of a round element. The clamping element here is a spring. These valves are mainly used on sanitary appliances.
The non-return-valve type is closed with a device of mechanical or manual type. The receiving. check valve is installed before the pump or at the end of the pipeline. They include a special grid that can protect the pump from foreign small elements. And the last sealing valves have a spool perpendicular (to the pipe) located.
If the check valve is not installed, then various accidents can occur. As for the material, the most reliable will be: brass, bronze, titanium and steel.
Water heater check valve. Design and principle of operation
It is difficult to imagine our normal life without hot and cold water. If the house has a well or borehole, it’s time to think about installing a boiler. Water heater installation can be done with your own hands.
A person who will install a water heater, should know how important it is to install a safety check valve for the water heater. No matter how horrible the accidents associated with heaters are, there are still people who think they don’t need advice. They will find this information unnecessary.
As much as we would like to, but still, there are very important details in the installation of the water heater.
The most popular search engine question for a water heater is “check valve for water heater”. It is more correct if we talk about the safety valve. These two devices have some similarities, but, at the same time, they are different. The main task of the device. To make the use of the water heater safe.
Why is the water dripping from the faucet
Dropping water signals of a faulty component, but even if the water is dripping at a great pressure, do not panic beforehand. This can be caused by several reasons:
In the first case, the malfunction could be due to the fact that the installation was carried out by non-professionals. Many check valves are manufactured with the ability to change the factory setting of the spring stiffness. The hardness should be adjusted by a specialist. If the settings have not been changed, the spring is most likely to be loose, in which case it is advisable to replace it with a new one.
If the cause of failure is due to high pressure in the pipeline, then before installing a safety valve, it is recommended to install a pressure reducing.
If there is excessive pressure in the pipeline, you can install a pressure-reducing valve at the entrance to the apartment, so you once protect all appliances in your home.
You will spend very little money to buy a safety valve and you will get safety and long life of your water heater.
Safety and check valve of the boiler. How to choose and install
Domestic hot water boiler refers to devices operating under high pressure and with hot coolants, so it is subject to the requirements of PB 03.576.03, regulating the mandatory installation of safety devices.
Safety valve for the boiler in modern heating systems performs 2 tasks: to protect the structure from the destructive pressure and the reverse flow of the medium, which occurs when the pressure in the tank of the electric water heater becomes higher than in the water network.
Design and principle of operation
Despite its fairly wide functionality, the safety valve has a very simple device: its main elements are two cylinders. a large and a small.

- The large cylinder is a kind of “check valve”. Inside it is installed a flap, which is called a “poppet valve”. This valve is actuated by a small spring. On both ends of the big cylinder, threaded parts are fixed, which are necessary to connect the safety valve with other elements of the boiler.
- The small cylinder is mounted perpendicular to the large cylinder. Both ends are plugged, and there is a drain tube on the body. There is also a check valve inside the small cylinder which works in the opposite direction to the first one.
How does the safety relief valve work?? An increase in water pressure within the boiler actuates the check valve spring. It opens, allowing water to fill the tank. As soon as the water reaches the correct level, the pressure inside the heater increases and the check valve closes. As the water in the tank is consumed, it will be replenished automatically.
The check valve inside the small cylinder is designed for higher pressure. As soon as this value is critical, a spring is actuated to open the valve. Thus, the excess water will be discharged.
There are several different modifications of check valves for boilers. They are differentiated by certain key parameters. For example, according to the method of installation check valves are divided into:
Depending on the principle of operation, the following varieties of check valves can be distinguished:
Finally, there are several other types of check valves for boilers according to the height of the lift of the shutter:
To understand why the valve is installed on the water heater, it is worth recalling your high school curriculum. According to the law of physics, water expands when heated. The liquid is inside a sealed container. If there is no water draw-off, the pressure rises, and the tank can burst. The safety valve for the boiler, which drains excess liquid from the tank, will help to prevent accidents.
On forums it is possible to meet the information, where it is advised simply not to put a check valve. Then there is no need to install the water pressure relief valve either. According to them, when there is excess pressure, some of the water will go back into the piping. Part of the advice is correct, but the system will work as long as the plumbing is stable. There are three reasons why this advice is wrong:
- There are no consistently working plumbing systems without failures;
- without a check valve, all the water from the tank will go into the empty piping;
- Bare heating element will heat the air inside an empty tank.
Now consider the end result of this problem. In case of plumbing failure, the pipes remain empty. There is no non-return valve on the inlet connection and the water from the storage tank flows freely into the system. The thermostat will turn on the heating element when the temperature drops. Without water, the heater will simply burn out, but that’s only half the problem.
There is another danger. The heating element is red-hot, and water appears in the water supply. Large amounts of steam and overpressure are generated sharply inside the tank and do not have time to vent back into the pipeline. The tank is guaranteed to burst in several places. Boiling water will flow into the apartment. For this reason, it is better not to make a wisecrack, and just install a discharge valve for water.
How To Choose Check Valve For Water Heater And Boiler
How to install the valve
Pressure relief valve is installed on the cold water inlet line to the boiler in accordance with the recommendations:
- between the valve and the water heater can not put a shut-off valve, only an American pipe to disconnect;
- It is necessary to run a hose from the safety valve to the nearest drain into the sewer;
- For convenient emptying of the tank between the valve and the water heater can be mounted T-branch with a ball valve on the branch. How to do this correctly is shown at
Usually there are no problems during installation, the operation is really not complicated. But the further operation, when constantly dripping from the safety valve, raises a lot of questions users. It should be understood that the mode of operation, in which water periodically dribbles from the discharge nozzle, is considered absolutely normal, for this reason and requires a pipe, diverting it into the sewer.
It is abnormal if it leaks all the time or never drips. Absence of drips may indicate a malfunction of the valve, so it is recommended to periodically force a little water with the appropriate handle.
Note. The absence of water dripping does not always indicate a malfunction of the safety device. In autonomous water supply systems with a pumping station the pressure does not exceed 3 bar and the valve may drip very rarely, so that you do not even notice it.
There can be two reasons why the safety valve leaks constantly:
In the first case it will help to install a new valve. But to change it to a device with a higher threshold would be a mistake, you risk destroying your electric heater or indirect water heater. There are two ways: to disregard and pay for extra water consumption or install an additional step-down pressure regulator at the inlet to the house.
Why do you need a safety valve
A boiler bleed valve is installed to ensure safe operation of the device. Water is a liquid coolant that tends to expand in volume when exposed to high temperatures. When heated to 80 90 ° C, the liquid expands by 3%. If, for example, in a boiler of 50 liters, appears 1.5 liters of “excess” liquid, the task of the device is to release the excess hot water.
Installing PC is a necessity, without which safe operation of the water heater is impossible. Failure to protect leads to pressure surges and excess fluid escaping into the plumbing system, which is energy inefficient and can lead to more trouble.