The geyser does not light up when turning on the water: what to do

Hello! There was such a problem: in the bathroom when turning on cold water, the pressure is good. When hot water is turned on, the pressure becomes weak, the column lights up (temperature 43 degrees). I turn on the shower, the column does not light up at all. Something with a mixer?

Expert Answer

Hello, thanks for the interesting question.

Since water is supplied to the gas column from the same line, which is used to connect the inlet to the “cold” valve, it is logical to assume that pressure losses occur in the water heater-mixer section.

In your case, you should check several key nodes:

1. Boiler. Very often, the heat exchanger of the water heater becomes the culprit of troubles. Due to the too thick scale layer on its inner walls, the hydraulic resistance of the system increases, which in turn leads to a significant drop in water pressure in the “hot” line. Indirectly this problem is also indicated by insufficient temperature at the outlet - the salt “coat” of the heat exchanger is an excellent heat insulator.
2. Water heater piping. It is imperative to check the performance and throughput of the tie-in line and the devices installed on it - the non-return valve, ball valves, filters, etc.
3. Mixer. Of course, the locking-mixing unit should not be overlooked. Perhaps he was just clogged.

The search for the weak link is from the valve. First of all, it is necessary to shut off the cold water supply tap installed in front of the water heater. After that, they remove the flexible connection of the “hot” valve and lower it into some deep container - a bowl, a bucket, etc. When opening the tap, they check the pressure. If the pressure is normal, then the mixer is to blame. No - the search continues. Each device should be turned off one by one until the culprit of the malfunction is found.

As for the second part of your question, namely, why the column does not light up when you turn on the shower, then everything is simple. The thing is that the flow sensor installed in the column has an activation threshold below which the gas valve is closed. When you open the faucet, most likely, the pressure is just right up close to trigger the water movement sensor. But the more distant and additional resistance watering can, the soul becomes that very last straw, because of which turning on the column becomes impossible.