VAILLANT VUW COMBI PRESSURE RISING OR FALLING NEEDS FAUCET, EXCHANGER, 3 WAY VALVE, EXPANSION TANK
When the pressure rises or falls, some boiler repairers can "deceive or replace the 3-way valve or the expansion chamber", which can lead to unfair gain. Of course not every combi is like this.
Do the tests yourself to be sure. I'll take a separate video on this later. I'm downstairs for now.
WHY THE PRESSURE Rises OR FALLS
a) The water pressure inside the boiler increases, even if the water filling does not completely close the tap. Until the drain is drained of excess water.
b) The pressure is increased if the blower is hole. When the heat exchanger is punctured due to corrosion, the water in the network installation, ie the water waiting to be heated in the heat exchanger, is mixed with the water in the heating system causing the pressure to rise. Easy to test if there is hole. This is not such a difficult job.
c) If the expansion tank is a hole, test as described below and this may cause a pressure increase.
d) If the 3-way valve is defective, if the ball in the video is stuck or worn, or if the engine does not work, it causes a pressure increase as it cannot close the water completely. Hot water may not come from the tap or hot water may not go to the honeycomb. If, like my fault, piston shaft gaskets become worn out, it causes water to drop and pressure drop. The repair kit of the 3-way valve shown in the video is 30 TL, with the brass body, the assembly is 90 TL, the original 350 TL
HOW IS THE EXCHANGER TESTED?
Turn off the main water and leave the hot water on and off. If the heating water comes from the tap and falls at the same time, the heat exchanger is the hole. Otherwise, it is robust.
Note: In order to completely close the boiler with the thought that the valve is not fully closed, notice that you can break the spherical arm as a result of turning too much.
OTHER TESTING: Test whether the pressure of the expansion tank has been dropped or that there is a hole.
HOW IS THE EXPANSION TANK TESTED?
If pressure changes only ON the boiler, the expansion tank can be suspected. Because hot water sent to honeycombs expands considerably. This expanding water is transferred to a place inside the installation to ensure that the installation does not explode. If the diaphragm gasket inside the expansion tank is punctured, the water inside it will be heated and the water inside it will be heated and the internal pressure of the boiler rises and the water is discharged from the drain cock. On top of the combi, the expansion tank is equipped with air slugs. Open the cover of this sibob and press the needle of the sibob briefly for 1.2 seconds; the expansion tank is the hole. If air is coming out, don't be afraid the pressure is reduced. If the pressure in the pressure drop in your combi, if the pressure in the water to cool down to 1 pressure in the water up to 1 even with a little warm water can rise up. A normal running combi is about half a bar. With a fine air pressure compressor, you can supply and measure a maximum of 1 Bar pressure. After pressing the hole of the most important tank, test the hole before draining the air again. Otherwise, you cannot print the correct amount of air. Never push more than 1 bar (14 ATÜ).
Respects