Installation of a gas boiler allows you to forget about cold water in batteries and taps. Double-circuit models are able to simultaneously work for heating and hot water supply (DHW) of the room. But what if the boiler does not heat water? If you encounter a similar problem, our recommendations will help you find the cause and fix the problem with your own hands.
The principle of operation of the boiler
To understand the causes of the breakdown, you need to understand how the boiler works. Double-circuit devices "Ariston", "Baksi" and other models have several blocks. Ignition and combustion take place in the gas unit, the water unit is responsible for the water supply and pressure in the line. The chimney unit displays the products of combustion on the street.
As soon as you start the boiler, a pump is activated, which pumps water into the system. The gas valve opens. The liquid circulates through the tubes of the heat exchanger, and the burner evenly heats its body. Sensors monitor the heating process. As soon as the temperature reaches the set, the gas supply is turned off, heating stops.
When the temperature starts to drop, the sensors will send a signal to the control module - the heating cycle will start again.
When the mixer is opened, the flow sensor is triggered. It gives a signal to the board to switch the three-way valve to heating the DHW. When the mixer closes, the valve switches to the heating system. Some models are equipped with a “quick start” mode. Then the valve periodically switches, heats up the first and second heat exchanger.
Why the boiler does not heat well, does not gain temperature
No hot water? For what reasons does the technique not work? Sometimes the matter is external factors. Let's consider in more detail.
The device works, but does not heat up or slightly warm
Airlock. Check for air in the batteries. Use the taps to remove excess air. If you do not have an air vent on the radiators, then you need to install it. By adjusting its faucet, you can lower the accumulated air in the system.
Also inspect the valve for blockage. Most often it is clogged with scale.
Radiator blockage. After cooling, drain the pipes. If it is very dirty, run the batteries until a clean one flows.
Incorrect connection. If there is no hot flow, make sure that the diameter of the pipes is as stated in the instructions. Are the hoses correctly connected? Isolation valves installed?
Low line pressure. It is not enough to open the valve and ignite the burner. Add water.
The accumulation of scale in the heat exchanger. You may notice that the equipment heats the liquid for a long time, the batteries are slightly heated. Clean radiator tubes from deposits. To do this, it is better to remove the unit, but this can not be done on all models. Therefore, remove the cover, disconnect the device from gas and water. Connect the tubing to the heat exchanger from the pump, run the cleaning fluid through the system. Special tools can be found in the store. Then rinse the parts with running water.
Adding reagents to the heat transfer fluid helps reduce salt formation on parts.
When buying, it is important to pay attention to the brand and model of the boiler. For example, manufacturers of Navien, Electrolux, Arderia, Ariston, Buderus prohibit the use of a reagent. It is recommended to install cleaning filters or use distilled water.
Antifreeze can be applied to the Baxi, Beretta, Vailant, Proterm, Celtic, Korea Star models. But for each manufacturer a separate reagent is produced.
Filter clogging. Another reason for poor battery warming. The strainer is clogged with small debris, so it is periodically removed and cleaned under running water. If the clogging or wear is severe, the part should be replaced.
Incorrect adjustment. Check the set values on the panel. The temperature may be too low, so the gas does not heat the hot water.
Problems with the circulation pump. Overheating, the pump turns off when hot water is turned on. Its power may not be enough for normal circulation. Adjust the settings.
Battery design does not fit your equipment. Each design has its own cross and heat transfer. Wrong choice leads to a decrease in heating due to the permeability of the system.
Non-compliance with the slope of the highway. The problem is typical for systems with natural circulation, which is ensured by the observance of installation standards. According to the documents, the slope of the pipes for each running meter should be at least 10 mm. No slope - no heat. The coolant stagnates, the batteries remain cold.
The gas boiler does not turn on, does not give hot water to the hot water supply
The main cause of malfunctions is salt deposits. The larger the scale layer in the heat exchanger, the worse the conductivity. The water heats for a long time, a thin, slightly warm stream flows at the outlet. Also a piece of scale could break off and block the passage to the mixer. What to do in this situation, we described above.
Flow Sensor Problems. The part works according to the principle of a fan, which rotates due to the movement of the flow. The sensor may not work when clogged. For cleaning without dismantling, open and close the tap located near the circulation pump.
If the procedure did not help to restore operation, you will have to remove the sensor, clean it and reinstall it.
Three-way valve malfunction. If the valve is stuck or broken, it will not be possible to switch the water supply from the heating system to the hot water supply. The cause of the problem could be a clogged part, gas hose or filter. Clean all items.
There are many causes of malfunctions. The symptoms described by us will help you determine what problem has occurred in your circuit. Pay attention to the operation of the equipment and compare with the indicated problems. If you can’t solve the problem yourself, contact a specialist.