Boiler and Boiler Installation and Testing

With the advancement of boiler technology and its ancillary equipment, the importance of maintenance training has also increased significantly, and only efficient and skilled people can undertake the maintenance of today's boilers. As a result, many companies are trying to abandon the previous maintenance methods and, by providing necessary training to management and maintenance personnel, rely more on a computerized and planned maintenance management system, based on which people must fill out pre-prepared tables.

Boiler Structure

Boilers usually include a plate, front and rear tubes, a furnace, and a return chamber, which after assembly and welding are first subjected to non-destructive testing (radiography, ultrasonic, liquid penetrant, etc.) and then stress relief is performed inside the furnace. The above boilers have two pipe passes, which together with the furnace have a total of three thermal passes.

A platform suitable for the weight, dimensions, and accessories of the boiler should be created in the boiler room. This platform should be at least 30 cm longer than the length and width (15 cm on each side) and 15 cm higher than the floor of the boiler house.

Boiler installation and commissioning:

After installing the boiler on the relevant platform and performing the necessary installation work, the following steps should be checked before commissioning:

• Remove the manhole cover.
• Check the inside of the boiler for dirt and foreign objects.
• Close the manhole again and make sure that the valves are tightly closed. (These steps should be carried out in the factory during the final test and this recommendation is for greater reliability).
• Check the front and rear inlet parts and chambers and make sure that they have not loosened due to transportation and are firmly in place.

Before draining the water, the water level gauge should be calibrated as follows:

1. The center of the water level gauge, which should usually be lower than the normal water level in the boiler, should be marked with N.W.L. Mark and place 12 mm above it as the pump off point.
2. Mark 12 mm below the N.W.L. as the pump on point.
3. Mark 75 mm below the N.W.L. as the Extra Low Water Level.
4. After marking in the above manner, turn on the pump and start drawing water until it reaches the pump off point.
5. Now adjust the relevant switch unit located inside the two-position water level controller so that the pump automatically turns off at that point.
6. Open the boiler drain valve until the water reaches the pump on point.
7. Now adjust the relevant switch so that the pump automatically turns on.
8. Then turn off the pump with the relevant switch and continue draining the boiler water until its level reaches the low water level mark.
9. Close the drain valve and set the switch unit in the water level controller to this position again so that the corresponding light turns on and the buzzer sounds.
10. Turn off the alarm with the Mute Alarm button, but the low water level warning light remains on.
11. Open the drain valve again and lower the water level until it reaches the very low water mark.
12. In such a situation, close the drain valve and set the switch unit (Control Level).

Test the boiler in the following order:

1. Turn on the pump by setting the switch to automatic mode and drain the boiler. When the water level reaches the pump off level, the corresponding pump will automatically turn off.
2. Open the drain valve until the water level reaches the pump on level, in which case the pump will turn on. Now turn off the pump and leave the drain valve open.
3. Check the next two steps, which are the first and second low water alarms, respectively.

1. Open the fuel return valves and bleed the fuel pump. (About 2 liters of fuel should be drained to make sure the fuel is completely bled.)
2. You should never turn on the burner motor before bleeding, but to speed up the process, you can turn the motor by hand. Make sure that the photocell (electric eye) is correctly positioned.

4. The tightness of the burner door is one of the things that must be checked carefully.
5. After ensuring that all fuses are intact, put them in place and check the motor speed with a very short start and if it is correct, turn on the boiler.
6. All the steps required to turn on the boiler are controlled at specific times by the timer installed in the electrical panel.

(LFL - SATRONIC - LEC1 timer, etc.)

7. After placing the burner switch (burner on/off) in the on position, the blower motor and burner start.
8. A few seconds later, the air damper in the blower path starts to open and (prepurage) works for 35 to 60 seconds to clean the smoke with full air in this state and then the damper returns to the low state.
9. The spark circuit, which is completed by a step-up transformer (220 volts to 8500), the corresponding spark plugs and the solenoid valve of the gas spark plug, comes into action and creates the appropriate spark.
10. In this state, the fuel and spark work simultaneously for a few seconds and then the spark is cut off and the flame becomes stable.
11. After the flame is stable, the command to continue the work is issued by the electric eye and the light corresponding to the normal flame (Normal Firing) is turned on and the electric eye controls the flame.
12. In the absence of flame, the command to shut down the system and a warning is issued by the siren and warning light, in which case the boiler manager is obliged to take appropriate action to resolve it.
13. It should be noted that at the beginning of the work, the flame adjustment switch is in the low or high position.
14. D can be (Modulation Hand / Auto) on automatic or manual mode.In this case, since the boiler is cold, it should not work with high heat or high flame, so it must be checked in advance that the flame adjustment switch is on manual mode and the potentiometer is on low mode, (it should be noted that the potentiometer device is installed on boilers with a capacity of 4500 kg/h and above) so that the body and water of the boiler are heated with low flame and steam is released from the air vent valve on the top of the boiler and the pressure rises to at least (bar 2) or (psi 30). When the boiler is completely emptied of air, the air vent valve can be closed.
15. In this case, if the flame is on high mode, there is no problem.
16. As the water inside the boiler heats up, its volume increases, which can be kept at a normal level by opening the drain valve.
17. To control the water level, the water level can be observed and controlled by observing the water level gauge.
18. If the boiler is operating at high flame and the pressure reaches (10/34 bar or 150 psi), the corresponding pressure switch (HIGH/Low Pressure Switch) is set to change the flame from high to low.
19. If the pressure exceeds 10/34 bar, the special switch (Boiler Limit Stat) automatically shuts down the boiler.