Boiler that does not make hot water

Boiler that does not make hot water

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Boiler that does not make hot water: possible causes, maintenance and plumbing do it yourself. What to do if the boiler no longer produces hot water.

What should be done if the boiler does not heat the water?We need to identify the cause and act upstream of the problem! On this page we will take the various hypothesescausesmaking an overview of possible solutions.

Remember that the boiler, even if powered by gas, needs electricity to work, so if there is no hot water and there is an electrical blackout ... this is normal!

When the radiators work but there is no hot water

It is not unusual: sometimes theboiler does not heat the watercurrent but has no difficulty in heating the radiators. In this case, there is usually a problem with the thermostat.

Check if the radiators are working: if the boiler manages to heat the house but cannot produce domestic hot water, you have to act on the thermostat.

Disconnect the heating from the thermostat and wait for the radiators to cool down. When the radiators are cold, open the hot water to check if the boiler operates regularly or if it turns off shortly after. If the boiler seems to work normally but the water remains warm (and does not heat up enough), check if the radiators, despite being disconnected, are hot.

If this scenario occurs (that is, if the water only cools down with the thermostat disconnected and the radiators are activated) then it is not the thermostat but it could be the diverter valve. The diverter valve diverts the hot water into the radiator circuit.

Again, if the boiler does not produce hot water but turn on the radiators, it could be a membrane problem; it is a component with a diameter of about eight centimeters, with a central hole. Here the operation is more complex because it will be necessary to access the internal components: remove the boiler cover!

You will notice a gray tank with a hinge and a fixing screw. The screw must be unscrewed. If your model is a boiler equipped with a front expansion tank, you will notice a black box on the right, where the board is located. On the left, however, there is the membrane placed inside a brass group equipped with a pressure switch.

Open the hot water and check if a small piston that closes the microswitch comes out of the brass group. If the piston does not come out, the diaphragm is the cause of the failure. You can remedy this problem by simply lifting the tab of the microswitch with a finger.

Another cause could be the inactivity of the burner. In this case the fault could be the blown fuse, which should be replaced.

Boiler not making hot water, causes

There are still other possible causes if yoursboiler does not heat water.

If the burner does not activate, the cause could be linked to a blown fuse that should be replaced.

Another cause could be linked to too low water pressure. or air intake or flue gas exhaust ducts that are too long. Try increasing the water pressure and check that the pressure gauge built into the boiler has a pointer between 1 and 2 atmospheres.

Boiler that does not heat hot water, solutions

As seen, the causes in case ofboiler that does not produce hot waterthey are multiple as well as different are the solutions described. Before implementing any solutions (from replacing the thermostat to intervening on the membrane), make sure you have the technical skills so as not to worsen the situation.

To save on the intervention of a plumber, try to contact different professionals and get the best price. If theboiler that does not make hot waterleaks from the valve or from other points in the circuit, read the guide dedicated to boiler leaking water.

Do-it-yourself boiler maintenance

Simple boiler maintenance can save your wallet. In our article dedicated toDo-it-yourself boiler maintenance we have seen how to perform basic checks and tricks:

  • Maintenance of the recirculation pumps
  • Control at the pump
  • Prevent and contrast the formation of limescale
  • Control of the rotating shaft
  • Temperature and efficiency control
  • Check the valves and any oxidative layers
  • How to bleed the radiators

Video: No Hot Water: Water Heater Troubleshooting (September 2022).


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