Description Of The Product; General Description; Operating Principle; Main Components - Baxi EVOlution PRIME 28 Manual De Uso

4.

DESCRIPTION OF THE PRODUCT

4.1 General description

This boiler has been designed to heat water to a temperature lower than boiling point at atmospheric pressure. It must be
connected to a central heating system and to a domestic hot water supply system according to its performance and power output.
The characteristics of this boiler are:
• low polluting emissions;
• high-performance heating;
• discharge of combustion products by means of a concentric exhaust connector or separate flue-air ducts;
• front control panel with display;
• minimal weight and size.
4.2

Operating principle

4.2.1 Combustion
The burner heats the heating water that circulates in the heat exchanger. When the temperature values of the combustion
gases are below the dew point (about 55 °C), the water vapour in the combustion gas condenses in the gas section of the heat
exchanger. Heat recovered during this condensation process (latent heat or condensation heat) is transferred to the heating water.
The cooled combustion gases flow out through the flue duct. The condensation water, instead, passes through a siphon.
4.2.2 Heating and production of domestic hot water.
Boilers for heating and the production of domestic hot water are fitted with an integrated plate exchanger that heats the domestic
water. The heated water flows through a three-way valve to the heating system or to the plate heat exchanger. A flow detector
signals the opening of a hot water tap to the electronic board which turns the three-way valve to its hot water position and starts the
pump. The three-way valve is spring-loaded and requires electrical power only when it switches position. Priority is given to DHW.
4.2.3 Central heating and domestic hot water with external storage boiler
Heating-only boilers with production of domestic hot water connected to an external storage boiler (optional) do not have the
integrated plate exchanger. The heated water flows through a three-way valve to the heating system or to an external storage
boiler (if fitted). The temperature probe of the external storage boiler connected to the boiler (section 6.6.9. Connecting an external
storage boiler) sends the heat demand to the electronic board which switches the three-way valve to its hot water position and
starts the pump. The three-way valve is spring-loaded and requires electrical power only when it switches position. If the boiler is
connected to the storage boiler, priority is given to the request for DHW.
4.3

Main components

1.
Heat exchanger (Heating)
2.
Hydraulic unit
3.
Plate exchanger
4. Safety valve
5. CH circuit water flow / DHW
tank
6. DHW outlet (G1/2")
7. Domestic cold water inlet
8. CH circuit water return
9. Pump
10. Three-way valve
11. Filling tap
12. DHW cold water inlet with
system filling tap
13. DHW tank return (G3/4")
24-26-28-30
2
4
5 6 7 12
7
1
9
10
M
3
4
11
8 5 13
1.24
1
9
10
M
11
12 8
BO-0000144
7730585(02-11/19)