How to keep the boiler of the professional dishwasher efficient
22 September 2023 -
What is the boiler and what is its function?
The boiler is an essential part of the professional dishwasher, as it ensures that the water used for sanitising dishes reaches the optimum temperature. However, the boiler can be susceptible to problems with calcification, corrosion or electrical faults, which compromise its operation and service life. To avoid these inconveniences, it is important to follow some simple rules of maintenance and prevention.

What to do to keep the boiler in good condition
- Carry out periodic cleaning of the boiler with specific products to remove limescale. This should be done at least once a month, following the dishwasher manufacturer’s instructions.
- Regularly check the condition of the boiler’s heating elements, which can be damaged by overloads or short circuits. In case of anomalies, replace the heating elements with original or compatible spare parts.
- Check the correct functioning of the boiler thermostat, which regulates the water temperature. If the thermostat is defective, the water may be too hot or too cold, compromising the quality of washing and the safety of operators. The thermostat should be replaced by a qualified technician.
- Protect the boiler from power surges or power cuts, which can cause irreparable damage. It is advisable to install a surge protection device or an uninterruptible power supply.
What not to do to avoid boiler problems
- Do not use water that is too hard or too soft to feed the dishwasher. Water that is too hard promotes limescale formation, while water that is too soft can cause corrosion. It is preferable to use a correctly calibrated water softener that adjusts the hardness according to the dishwasher’s characteristics and the type of water in a certain area. The water in the water system should have a hardness of no less than 14°F-15°F with a maximum amount of sodium dissolved in the water of 200 mg/l, but better not to exceed 150 mg/l. If the hardness should be higher, the use of a water softener to be placed on the water supply pipe is recommended. In fact, a water hardness that is too high will cause limescale deposits on the boiler, heating elements and tank, as well as in the entire hydraulic circuit, which will affect its efficiency and correct operation. In the case of water that is too soft, and therefore with a low hardness, this would be particularly aggressive due to the excess sodium ions dissolved in the water, which promote corrosion of the steel. Adjusting the softener from this point of view is strategic, to avoid excessive water hardness, which not only causes corrosion problems, but also increases consumption of both water and salt.
- Do not use detergents or rinse aids that are not suitable for commercial dishwashers. These products can be aggressive for both the boiler and other parts of the machine, as well as leaving residues on the dishes. It is important to choose products specifically for the professional dishwasher, following the manufacturer’s recommended doses. Therefore, use good quality, non-corrosive dishwashing products and above all WITHOUT chlorine (bleach contains a lot of it). Corrosive or chlorine-containing products can cause corrosion to the point of puncturing the boiler or wash tank.
- Do not introduce objects with iron oxide (rust) into the washing chamber. Rust will corrode and puncture stainless steel surfaces.
- Ensure that the earth connection of the system is efficient. An improperly functioning earth connection causes the tub and boiler to be punctured by stray surface currents.
- Do not open the dishwasher door during the wash cycle. This action interrupts the flow of hot water from the boiler and can cause damage to the heating element and thermostat. In addition, you risk scalding yourself with steam or boiling water.
- Cleaning of the washing tank and accessories must be done with non-corrosive products and especially WITHOUT chlorine.
Boilers with special steels
The boilers of professional dishwashers are usually made of aisi 304 stainless steel: in very specific situations where the machine comes into contact with particularly hard water rich in corrosive agents, there are special boilers made of aisi 316 stainless steel.
Both types of steel, 304 and 316, are part of the so-called austenitic steels, but going into detail, the main difference is the presence of Molybdenum in AISI 316. This element is in fact able to increase the corrosion resistance of 316 steel compared to 304, even in very reducing and highly saline environments.

By following these simple tips, you can guarantee your professional dishwasher’s boiler a long life and optimal efficiency, while saving on repair and replacement costs.
Contact us for more information on our boilers and our professional dishwashers for bars and restaurants made entirely in Italy
Sistema Project Italia staff