Electric buffer heaters, heat pumps and large volume sanitary water heaters are key components of modern heating systems. These devices enable safe and efficient space heating and ensure complete comfort and thermal balance in homes, commercial facilities and industrial plants.
As an auxiliary component of the heat pump, the electric heater has several applications:
1. To support the operation of the heat pump, installed – installed as part of the pressure branch of the heat pump pipeline
2. To support the operation of the heat pump installed – built into the buffer
Electric heaters provide support in the operation of heat pumps at times when the heat pumps cannot provide a sufficient amount of heat energy by their own operation. In this situation, the control unit of the heat pump activates the electric heater as an additional source of thermal energy in order to provide a sufficient amount of thermal energy for heating the space, sanitary water or some other purpose such as heating the water in the swimming pool.
During the winter months and low outside temperatures, heat pumps, depending on the type, stop working at temperatures lower than -15° or -20°C, and then the role of the primary source of heat energy becomes electric heaters. In addition to providing heat energy for space heating, sanitary water heaters at these moments also serve as a protective component for heat pumps to protect heat exchangers from cracking due to low outside temperatures.
3. To support the operation of the heat pump installed – built into the sanitary boiler
With sanitary boilers, electric heaters have a double role, the first and basic purpose is to reheat the sanitary water in moments when the heat pumps cannot reach the set temperature. Another purpose is very important for users of sanitary water, which is to use electric heaters to sanitize pipelines and water heaters from Legionella bacteria. Given that heat pumps provide a maximum temperature of the fluid in the exchanger up to 55°C, and that for the prevention or cleaning of the system from Legionella, a temperature of approximately 65°C at the valves are recommended.
The advantage of electric heaters is their simplicity and ease of use, which makes them a popular choice for the auxiliary or safety component of innovative heating methods that use renewable energy sources such as heat pumps.
The advantages of electric heaters for buffers, heat pumps and sanitary water heaters of large volume are:
- Fast heating (short response time)
- Low initial investment
- Easy installation and maintenance
- Adjustable temperature and heating control
Table of recommended power and heater length in relation to boiler volume:
Models of electric heaters are differ in the following characteristics:
1. According to power of the heater:
- Single-phase models from 500W to 3.500W
- Three-phase models from 500W (3x500W) to 15.000W (3×5.000W)
2. By connection voltage:
- Monophase 230V AC
- Three-phase 3x230V (400V) AC „star” type of connection (Y)
- Three-phase 400V AC „triangle“ type of connection (△)
3. By the thread size of the flange and the level of protection of
the connection box
- R5/4“ – G1 ¼“ (IP44 i IP65)
- R6/4“ – G1 ½“ (IP44 i IP65)
- R2“ – G2“ (IP65)
- R2 ¼“ – G2 ¼“ (IP65)
- R2 ½“ – G2 ½“ (IP65)
4. By the material of tube of the heater
- Prochrom Aisi 316L
- Prochrom Incoloy 800
5. By thermostat:
- Without an integrated thermostat (the heat pump controls the heater)
- Single-phase rod thermostat without external regulation
- Single-phase rod thermostat with external regulation
- Single-phase capillary thermostat
- Three-phase stick thermostat
- Three-phase capillary thermostat