What to do if the gas water heater does not heat water
The main and main purpose of gas boilers is fast heating of cold water in an apartment or private house. But this device, despite its relatively simple device, requires regular maintenance, otherwise it works worse and worse up to the complete cessation of its functions. In a situation when the gas water heater does not heat water, there are two ways out: the first. you can ask for advice and help from professionals, the second. to try to make diagnostics and fix the problem on your own. In the latter case, you need to know the principle of operation of the gas water heater and understand the types of breakdowns that can occur with the device.
The principle of operation of any gas water heater, whether it is modern or old Soviet, is very simple. Inside the device is fed gas, which in the combustion process emits heat, heating the heat exchanger and the coil passing around it, along with the flowing water. It turns out that in the speaker from the water supply is fed cold water, which as it moves along the coil is heated, and already hot water moves to the point of intake: a tap or shower. In this case, the combustion products of gas are led into the chimney, and from there to the street.
There can be many reasons why the heater does not heat water. These include:
- long absence of maintenance of the device;
- The membrane has lost its elasticity due to long-term operation;
- clogged chimney;
- Wear of the heat exchanger;
- malfunction of the ignition system;
- weak water pressure;
- A problem in the water supply system;
- scale formation;
- Low-powered burner.
So that the gas boiler starts to heat water again, you need to make a diagnosis of the device, to identify faults and fix them on your own or with the help of a specialist.
What you need to do first?
First, check whether the wall boiler really does not heat water. The design of any boiler implies technical limitations. This also applies to the preparation of hot water. The gas boiler with power of 24 kW can heat 12 liters of water. The temperature difference in this case will be around 35 degrees. You can clarify the technical characteristics of your appliance by reading its user manual. Any deviations from the parameters indicated in it indicate a malfunction of the device. Some gas boilers today are equipped with a diagnostic system that displays the error code on a special screen. You can also decipher these codes in the manual.
Parallel connection of two appliances or overflow in the plumbing faucet
In this case, the hot water coming out of the boiler to the tap is almost cold. This is caused by the so-called underflows. People sometimes use an electric boiler along with the boiler, after turning it off, they simply forget to shut off the water supply. What happens in the end? Part of the water entering the faucet is heated in the boiler, and the other part goes through the cooled boiler. Then the two parts mix together with a natural decrease in temperature. Because of overflows, it’s not uncommon for cold and hot water to mix in flagged single-lever faucets. This is not a malfunction, but a slight malfunction of the system, which can be easily eliminated. If the user has set the maximum temperature, but the water from the boiler comes out a little warm, then the cause of the fault is the boiler itself or the system of its power.
Scaling in the boiler three-way valve or in the secondary heat exchanger
The water contains many different impurities, which are deposited on the heating surfaces when heated. Approximately the same happens in your kettle, only in a much smaller amount. The thermal conductivity of such salt deposits is several times lower than that of the heat exchanger metal. Scale layer gradually increases so much that it begins to flake off, which the flow of the coolant is carried either in the three-way valve, or in the secondary heat exchanger. Limescale gets into the valve and prevents it from switching over properly. Part of the coolant is discharged into the heating system because of this. As a result. reduced amount of coolant to heat water in the secondary heat exchanger and gas two-circuit boiler does not heat hot water. And what if the scale gets in the secondary heat exchanger itself? Then there is a violation of normal circulation of the coolant in the small boiler circuit. This in turn leads to a reduction in the amount of heat required for heating. It is worth thinking about installing special magnetic or electromagnetic filters to help combat the formation of limescale.
Clogging of the secondary heat exchanger due to poor quality plumbing water
The secondary plate heat exchanger of the boiler
Bad plumbing water promotes the accumulation of deposits in the heat exchanger. Heat transfer over time deteriorates, and the boiler ceases to heat water normally. Sometimes this problem can be solved by flushing, but in some cases the secondary heat exchanger will need to be replaced. If the bithermal heat exchanger fails, it will have to be replaced. Keep in mind that this part is not cheap.
Narrowed gas passage or fuel starvation of the boiler
If the gas pipeline is heavily clogged or its cross-sectional area is narrowed, it will lead to gas starvation of the boiler. In simple words, the boiler will not have enough gas to reach its maximum output and therefore does not heat enough water.
Failure of the gas valve or improper adjustment by the user
Valves of some boilers stop working when there is dirt or dust in the gas. As a result, the valve begins to jam, and it stops opening at full capacity. The process of water heating is naturally disturbed. In rare cases, the valve settings are knocked down so much that the boiler itself can not work as intended. It will be necessary to adjust the boiler control system or replace it completely.
Insufficient pressure in the heater
Water valve can stop opening due to low volume of liquid in the system that does not create the necessary pressure. Check operation of all fittings and valves, as well as the pressure of water flowing out of the mixer. If there are no leaks and the head is low, refill the water in the expansion tank.
The seventh reason. airlocks in the pump, leading to malfunctions. In these cases, disassemble the pump and check what caused the clogging.
Another reason for the lack of hot water in the two-circuit boiler can be a malfunction of the water flow sensor, they are often blocked by foreign particles. Sensor must be disassembled, thoroughly cleaned and turbine flushed.
After determining the cause of poor water heating, proceed to its elimination. Manufacturers often make the mechanical components of the devices available for service, which facilitates the repair procedure.
Attention! Do not try to repair the boiler with your own hands, if you are not confident in your own abilities. But, if you have already decided to make your own repairs, do not forget to disconnect the heater from the power supply.
To make your gas boiler last as long as possible, always follow the rules of operation. Read the manual carefully. Carry out regular preventive maintenance checks. Remember that the repair will cost you more than the scheduled replacement of parts or manual descaling.
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What are the reasons for incomplete fuel combustion??
In the physical and chemical process of combustion of the limiting hydrocarbon and its subsequent products, carbon dioxide is formed. It happens that there is no fresh air inlet and during combustion, in addition to carbon dioxide products, carbon monoxide in the form of dirt and soot is formed. By the way, carbon monoxide exists in all gas burners, this is its usual state. It can’t be avoided. Sometimes for the cleanliness of the internal walls of the burners are installed combustion chambers, where the combustion process takes place. Ducted water heaters do not use such chambers. To look at the combustion process, you can remove the front panel of the gas burner and look at the inside of the appliance.
Sometimes the panels are dirty and smeared with soot. To clean them, allow air to flow into the chamber and clean the appliance. For one cubic meter of gas to burn properly, it will require about ten parts of fresh air. In devices designed for gas generation, everything is provided in advance, with a specially installed air valve can provide free access of fresh air into the chamber.
Remember not to neglect the cleaning of the heat exchanger panels, because as a consequence of this threatened with poor water heating and overconsumption of fuel.
What else can interfere with water heating?
If diagnostics showed that there are no malfunctions in the gas heater, but the heater still does not heat or badly heats water, it is worth to listen to the recommendations of professionals.
To increase the temperature of water at the outlet of the heater, you should open the gas tap as much as possible, and the valve responsible for the flow of cold water, open only halfway. At maximum power of the burner, the flow of cold water will decrease. This will provide better heating.
Compliance with the rules of operation of the device, periodic maintenance, will reduce the likelihood of breakage, enjoy hot water without hassle. If there are failures in the work of the gas boiler, you can fix minor defects, clean the filters, change the gaskets. Replacement of the temperature sensor, adjustment of gas supply will have to entrust the representatives of the gas service, which have the permission to carry out such work.
Wear of the heat exchanger is the second reason why the gas water heater does not heat water
In long-term operation (several years, in defective models can even be up to a month or less) a hole can appear on the radiator, and the water will leak. If the part is not made of solid copper, but with impurities. the problem occurs regularly. The part is oxidized and gradually gives way to destruction.
The main solution. full replacement of the element. If there are small holes. you can try to solder, but it will not give a long-term result.
How to light a hot water heater pilot / No hot water
How warms the water in the gas water heater
There are two types of gas water heating equipment: storage and flow-through. The heat source is the combustion gas. Heating water and supplying it to the consumer differs depending on the type of column:
- Gas-flowing water heater. the burner is located under the coil, inside which the water is constantly circulating. When gas burns, heat is released, heating the heat exchanger. The heated liquid is delivered to the consumer. Water temperature is controlled by the speed of its movement inside the heat exchanger and the intensity of the flame.
- Accumulation gas water heater. the difference from the flow heater is that first the air is heated, under pressure is sent into the flame tube, which acts as a heat exchanger. Further heating process takes place as in the electric boiler. Water flows around the heated flame tube. The process of heat transfer takes place. The hot water is stored in an insulated storage tank. For the first heating of the portion of water, it takes 30-40 min.
A new flow heater or storage water heater, if properly connected, should work without failures and violations, heating DHW to a specified temperature. If immediately after installation, the automation gives an error, the main burner does not turn on or the water remains cold when there is a flame, the reason lies in violation of the rules of installation and placement of the water heater. Problems occur in the internal unit during operation.
The following are common malfunctions and their signs.
Causes of problems
Water heater does not heat properly, cold water flows from the tap? What could have happened:
- Thick layer of deposits on the external walls of the heat exchanger (radiator). Soot and soot accumulate during operation: the thicker the dirt layer, the harder it is to heat the flow. This leads to the fact that the appliances “Neva”, “Ariston” and other brands do not heat the content.
- Weak flame in the burner. Means that the diaphragm is faulty or worn, so it does not create enough pressure on the gas valve.
- Overheating of the radiator. Impurities from the water supply will settle on the walls and components in the form of scale. It is difficult for the radiator to release heat into the environment, which leads to overheating.
- Insufficient pressure in the gas line. You need to wait for recovery or contact the gas service.
- Untimely maintenance of equipment. Periodically, the parts need to be cleaned, as well as to check their functionality.
Let’s consider in detail all causes of malfunction and ways to eliminate them.
How to fix the problem?
If the body of the gas heater is warm due to contamination in the communications, they should be cleaned. It is necessary to check the water supply and drain hoses, the boux tap and the cartridges for the faucet. Hoses are cleaned under running water.
To clean the pipes, you can use a reverse current or ask for help from a master
If the regulator is installed incorrectly, the water heater must be switched to summer mode. The original outlet water temperature is affected by the temperature of the fluid at the inlet. For example, the unit heats water to 35°C.
In summer, the water inlet temperature is 15°C. Consequently, the liquid heats up to 50°C at the outlet. In winter, when the inlet water temperature is lower, this indicator also decreases.
What rules should be followed to ensure that the water pressure in the gas water heater will always be strong
There are simple rules of operation to avoid having to run to the store constantly for citric acid or to wash the parts of the boiler, breaking it down into atoms.
It is better to know the problem and not to let it happen, rather than spend money on repair accessories or a new boiler.
- Take a bath or shower with a water temperature not exceeding 40 °C. This indicator is good for your body (not too cold) and will not cause unnecessary limescale buildup.
- For a dishwashing or washing-up, 45-50°C is enough. Water is comfortable for hands, and the grease on the plates is already washed.
- The washing machine is enough temperature 45-50 °C. If things are very dirty. put about 5 °C more.
This temperature has been selected for a reason. All because lime deposits appear at temperatures up to 80 Celsius. Scale is deposited even on perfectly clean surfaces, and the boiler begins to “hurt”.
Gas Water Heater Not Heating? — Gas Water Heater Troubleshooting
And to make sure that doesn’t happen, keep an eye on your appliances. Have a nice and happy day!