The flow heater consists of several units. The principle of operation of the device is simple, but individual blocks require special attention. In the article, we will consider the water unit of the gas column. What kind of work it does, what materials it is made of and what principle of operation it has, you will learn below.
Design and types of water block
The material for the manufacture of a water reducer is different, therefore it is divided into several types:
- Brass. An alloy of copper and zinc.
- Plastic. The practical device is not subject to corrosion.
- Polyamide. Reliable device with fiberglass in the composition.
The column regulator or “frog”, as the block is also called, has protective functions. It serves to automatically turn on the device when water is supplied. It also protects against overheating when the pressure in the line decreases.
How the gearbox works:
- Base and cover with bolts.
- Rubber diaphragm with disc on stem.
- Flow device.
- Temperature switch.
- Flow sensor.
- Ventura tube.
- Filtration device for hot water.
See diagram:
The water pressure regulator cover can be fastened with steel screws or plugs. Since the parts do not come into contact with water, there is no risk of corrosion. By unscrewing the screws, you will remove the cover behind which the membrane is located. The device is quite simple.
When the water is turned on, pressure is created on the membrane. It pushes out the stem, which actuates the gas valve. Fuel is supplied to the burner and heating starts. When the mixer closes, the pressure drops – the parts return to their original position.
An important part of the gas-water unit is the Venturi nozzle. What is it for? For example, in the Neva technique, the tube is in the lower part. The location in the columns “Oasis”, “Astra” may differ. The part serves to reduce the pressure of the working medium. This is how the gas supply is regulated.
When you close the faucet, the tube equalizes the readings, due to which the membrane fitting returns to its place. After that, the device turns off.
The water part is also prone to breakdowns, so we will list the main malfunctions and ways to repair it yourself.
Typical Block Problems
Most often, the node fails due to poor-quality water. Impurities of potassium and magnesium settle and clog the details of the device. Pressure drops in pipes also affect. It has been proven that 80% of breakdowns of gas heaters occur due to the failure of the water-gas unit.
Learn the main signs and causes of breakdowns.
The water pressure is normal, but the burner does not ignite
- Check the membrane. The rubber element wears out quickly, tears, flows. Instead of the old element, it is better to install a silicone membrane.
- The stem is stuck, does not move. Perhaps he got hooked. Lubricate this area and the oil seal with reconditioning grease.
The cold flow is strong enough, but the hot flow is weak.
- The mesh filter is clogged with small debris, rust. Remove and clean the part.
- The nozzle at the entrance to the node is clogged. Cleaning is also done.
When you open the mixer, the column does not start immediately
- The channel of the retarder ball is clogged. Disassembly and cleaning of elements. The ball is in the cover of the assembly.
- The retarder ball is incorrectly adjusted. You need to tighten the adjusting screw.
After closing the taps, the device does not stop working
- The ball is jammed, or its channel is clogged.
The equipment does not work at full capacity, during operation it may go out
- The membrane is damaged. The defective element needs to be replaced.
If you find a malfunction and decide to do the repair yourself, read below how to remove the gearbox.
Dismantling of the water unit
To carry out repairs, the unit must be removed from the seat. This is possible only together with the dismantling of the gas unit.
- Shut off the gas supply valve.
- Disconnect the cold water hose.
- Using the wrench, disconnect the assembly from the nozzle.
- Disconnect wiring from gas valve and microswitch.
- Loosen the flange bolts with a screwdriver.
- Remove the water block.
Now you need to disassemble it and replace the broken parts:
- To disconnect the gas part from the water part, unscrew the two screws. One is at the top, the other at the bottom. You can not unscrew it completely, but slightly loosen the mount. It happens that the bolts stick. Spray these areas with WD-40.
- Disconnect the blocks.
- Now unscrew the “frog” screws from above.
- The body will be divided into two parts and the diaphragm will become available.
- Remove the rubber part (in case of failure, prepare a new one).
- Pull out the stem disc. Behind them is a spring.
- Remove the spring and check the seal located behind it. It requires periodic cleaning and lubrication.
- Install new parts and assemble the block in reverse order. The seal can be lubricated before installation.
- When tightening the frog bolts, lubricate them with graphite grease.
In order not to run the column to a faulty state, check its components every six months, clean it from scale and dirt.