First, the basic principle and workflow of wall-hung boiler
1, working principle
When the wall-hung boiler is started, after the system pressure is normal, start the water pump to push the heat medium water to flow, turn on the water flow switch or the water flow sensor, and output the water flow signal (switch signal or pulse signal) to the main controller. After receiving the water flow signal, the main controller starts the fan for pre-cleaning to check whether all kinds of safety devices are normal. When all the safety devices are normal, ignite and open the first and second valves respectively. The gas enters the burner and is ignited by electric spark for combustion (in the ignition process, the fan usually runs at half speed or by inertia when the power is off, and the fan speed is determined according to the gas quantity after ignition and combustion. For vehicles using gas proportional valve, the proportional valve can be divided into ignition current, minimum current and maximum current, which can be adjusted separately). The flame is normally burned by ion induction flame technology, and the heating medium is emitted into the air or radiated by radiator to achieve the purpose of heating. After reaching the set heating temperature, turn off the fire and enter the standby state. Repeat this cycle.
2. Working process
The heating system is normal → the pressure of the detection system is normal → the water pump works → the water flow switch or the water flow sensor is turned on → the water flow signal is output → the fan is cleaned before entering → the wind pressure is detected to be normal, and all safety devices are normal → ignition (the fan enters low-speed operation or power-off depends on inertia operation) → the primary and secondary electromagnetic valves (proportional valve automatically enters the ignition volume, and the segmented valve enters the small fire ignition) → ignition → ion flame induction, normal combustion, and the fan enters the normal speed →
I. Failure phenomena, causes and solutions
1, insufficient pressure fault
Fault phenomenon: the water pump is not running, the controller gives an alarm, and the display screen shows that the fault code is insufficient pressure.
Reason for failure:
A) the pipeline is short of water, and the pressure gauge shows that the pipeline water pressure is insufficient.
B) pressure switch failure.
C) There is a lot of air in the pipeline system.
Solution:
A) water supply pipeline is short of water; If the pipe leaks, try to stop it.
B) check with a multimeter. If the pressure switch is not connected, replace the pressure switch; If the contact is poor, reconnect; If the line is open, replace the wire; If you insert the wrong terminal, please press the correct connection.
C) Drain the piping system.
2, pipeline water shortage fault
① Fault phenomenon: the water pump does not operate, the fan does not operate, the controller gives an alarm, and the fault code displayed on the display screen is water shortage in the pipeline.
Cause of failure: a) The power cord of the water pump falls off.
B) the water pump is not locked for a long time.
Solution:
A) Use a multimeter to check whether the output power of the water pump is normal and whether the contact is good. If the controller has no voltage output, it is a controller failure, and the controller is replaced; If the controller has voltage output and the water pump has no electricity, it means that the connector has fallen off, poor contact or broken wire; If you drop it, contact me again. If the contact is not good, I will contact you again. If the wire is disconnected, it will be replaced.
B) If the water pump has voltage input, it may be locked. Unscrew the screw on the water pump and turn the shaft of the water pump with a screwdriver to make the rotor of the water pump rotate and return to normal; If the water pump is not locked, use a multimeter to detect the open circuit or short circuit of the water pump, indicating that the water pump is burnt out and needs to be replaced.
(2) Fault phenomenon: the water pump is running, the fan is not running, the controller gives an alarm, and the display screen shows the pipeline missing fault code.
Reason for failure:
A) The air in the water pump is not exhausted, which leads to the idling of the water pump.
B) The distributor of the heating system is not opened or the filter is blocked.
C) there is air in the pipeline.
D) water flow switch failure.
E) The pressure difference generated by the pipeline of differential pressure machine is not enough.
Solution:
A) Unscrew the slotted copper screw on the end face of the water pump, exhaust the air in the water pump, and restart.
B) If the distributor of the heating system is not opened, the distributor is opened; If the filter is blocked, remove the filter, rinse, install, replenish water and exhaust, and restart.
C) If there is air in the pipeline and it is not exhausted, restart it after exhausting.
D) water flow switch fault with multimeter to detect whether there is a switch signal output in the operation. If there is a signal output, the water flow switch is connected, maybe the connector is not connected properly, or the wire is disconnected, then connect the connector or replace the wire; If the wires and connectors are in good condition, the controller is faulty and replaced. If there is no signal output, the water flow switch is stuck or the waterway is blocked; If water flow switch gets stuck, remove the water flow switch, rinse it and put it back in its original place; And hydration. Exhaust and restart; Waterway blockage should be handled according to method B.
E) Install a distributor (switch) at the heating outlet and turn it down.
3, fan wind pressure fault
① Fault phenomenon: the fan is not running or running slowly, the controller gives an alarm, and the display screen shows the fan wind pressure fault code.
Reason for failure:
A) The fan is stuck or burnt out;
B) poor contact of the connector
C) controller failure
D) capacitor damage
E) the main pressure is too low.
Solution:
A) Check the fan with a multimeter, replace the fan when disconnected, and replace the fan when stuck.
B) The connector is poorly contacted and reconnected.
C) If the controller fails, replace the controller.
D) If the fan impeller can be started by hand, the capacitor will be damaged and need to be replaced.
E) install the voltage regulator and increase the power supply voltage to 220V.
② Fault phenomenon: the fan is running normally, the controller does not ignite, the main controller gives an alarm, and the display screen shows that the fault code is fan air pressure fault.
Reason for failure:
A) wind pressure switch short circuit
B) the wind pressure switch is not turned off.
C) poor connector contact.
D) The suction port and exhaust port are blocked.
E) controller failure.
Solution:
A) check with a multimeter. If the wind pressure switch is turned off before the fan starts, replace the power supply or adjust the wind pressure switch.
B) If the fan is normal before starting and does not turn off after starting, the air pressure switch can be adjusted. If the problem cannot be solved after adjustment, please replace the air pressure switch. ; In addition, check whether the venturi tube or the wind pressure tube is blocked.
C) If the connector has poor contact, please reconnect it.
D) If all the previous faults are eliminated, check whether the air intake and exhaust are unblocked or blocked; If the suction and exhaust are not smooth, clean the flue, if it is blocked, clean it.
E) If faults A, B, C and D have been eliminated, check whether the pulse igniter connector is in good contact and whether the main controller has a voltage of 4.5V If the contact is poor, the connection is good; If there is 4.5V output, replace the pulse igniter; If there is no 4.5V output, please replace the main controller.
1, ignition failure fault
Fault phenomenon: the pulse igniter ignites normally, but does not ignite, the main controller gives an alarm, and the display screen shows the ignition fault code.
Reason for failure:
A) The ignition spark is weak due to the breakage of the insulating porcelain body of the ignition needle or the looseness of the metal needle.
B) Abnormal power supply to the air valve causes the solenoid valve to fail to open.
C) proportional valve ignition current adjustment is unreasonable.
D) small fire of sectional valve and unreasonable gas flow adjustment.
E) Foreign matters accumulated in the gas valve make it start badly.
F) The rubber eardrum of proportional valve is bad.
G) solenoid valve coil is damaged (short circuit or open circuit).
H) gas pressure is too high or too low.
I) Connect the high-speed and low-speed cables of the two-speed fan.
J) The relevant parameters of the ignition needle are incorrect.
Solution:
A) replace the ignition needle.
B) replace the main controller.
C) Adjust the reasonable ignition current of proportional valve.
D) Adjust the reasonable small fire gas flow of the sectional valve.
E) Remove foreign bodies from the air valve.
F) Replace the gas valve.
G) replace the solenoid valve.
H) Adjust the gas pressure to the rated pressure.
I) Connect the high-speed and low-speed cables of the two-speed fan correctly.
J) If the ignition needle is too large or too small, adjust it to 3 ~ 4mm；; Adjust or replace the ignition needle when the direction of the ignition needle deviates seriously, and adjust it reasonably when the distance between the ignition needle and the burner is too far.
2. Unexpected flameout failure
Fault phenomenon: flameout occurs after ignition, the main controller gives an alarm, and the display screen shows an unexpected flameout fault code.
Reason for failure:
A) carbon deposition on the flame induction needle.
B) The connecting wire of the flame induction needle has poor contact.
C) The suction and exhaust ports are blocked or the flue gas inlet does not extend out of the wall.
D) There is too much downward airflow outside.
E) abnormal gas pressure, too high or too low.
F) controller failure.
G) the flame induction needle does not touch the flame.
H) The flue is not installed correctly.
I) Put the air inlet pipe and exhaust pipe into the flue.
J) The grounding wire falls off or breaks.
Solution:
A) Remove the carbon deposit on the flame induction needle.
B) The flame induction needle connecting wire is well connected.
C) Clean the air intake and exhaust port to ensure smooth air intake and exhaust.
D) Change the position or direction of suction and exhaust.
E) Adjust the gas pressure to the rated gas supply pressure.
F) replace the controller.
G) In case of fire or small fire, adjust the flame induction needle to the position where it can contact the flame. Preferably, it is the junction of the inner flame and the outer flame of the flame.
H) It is forbidden to connect the intake and exhaust flue to the public flue and move it outdoors.
I) If the smoke pipe is removed normally, it means that the smoke pipe is not connected correctly, and then the smoke pipe is reconnected.
3, overheating fault
Fault phenomenon: the wall-hung boiler flamed out, the main controller gave an alarm, and the fault display screen showed the overheating and dry burning fault code.
Reason for failure:
A) When the heating distributor is closed, the water temperature of the main heat exchanger rises rapidly, and the hot water temperature exceeds 90℃, which leads to the opening of the bypass valve.
B) The heating pipe is blocked, which slows down the water circulation, resulting in the rapid rise of water temperature and the hot water temperature exceeding 90℃.
C) The thermostat for overheating protection is not good, and it should be normally closed instead of normally closed.
D) The flow switching function of the three-way valve is disordered (three-way valve type), which may be due to the dislocation of the connecting pipeline or the dislocation of the ball assembly and the poor rotation of the ball, resulting in a small circulation of hot water entering the plate heat exchanger through the three-way valve during heating and a sharp rise in water temperature.
E) controller failure.
F) The distributor (switch) is installed in the opposite direction.
G) the filter is blocked.
Solution:
A) Turn on the heating distributor.
Clear the heating pipe.
C) Replace the overheat protection thermostat.
D) if the connecting wire is not aligned, correcting the connecting wire; If the ball assembly is misplaced, please assemble the three-way valve ball correctly; If the ball rotates badly, replace the three-way valve.
E) replace the controller.
F) Reassemble the distributor (switch) to make it in the correct direction.
G) clean the filter.
4, temperature sensor failure
Fault symptoms: the wall-hung boiler is turned off, the main controller gives an alarm, and the display shows the fault code of the heating or hot water sensor.
Reason for failure:
A) temperature sensor is short-circuited.
B) the temperature sensor is open.
Solution:
A) If the insulation layer of the connecting wire in the line is damaged and short-circuited, replace the conductor; If the temperature sensor is damaged, replace it; If the controller is damaged, please replace it.
B) If the connection in the line is broken or poorly connected, replace the conductor and reconnect it; If the temperature sensor is damaged, replace it; If the controller fails, please replace the main controller.
5. Although the open wall-hung boiler runs normally, the water tank overflows.
Fault symptom: the water tank overflows.
Reason for failure:
A) The automatic water replenishing valve is blocked by sundries, causing tap water to flow into the heating water and overflow.
B) Water overflows due to water leakage inside the plate heat exchanger.
C) The heating system is too large, which does not match the expansion tank and overflows.
Solution:
A) If the rubber film of the automatic water replenishing valve is attached with foreign matter, resulting in poor sealing, please remove the foreign matter; If the water supply valve is not closed correctly, please replace the automatic water supply valve.
B) Replace the plate heat exchanger.
C) Install a check valve on the heating pipeline or replace a large-capacity open water tank.
6. Although the closed wall-hung boiler is running normally, the pressure is rising.
Fault phenomenon: the pressure of the water gauge keeps rising, and the pressure reducing valve drips for a long time.
Reason for failure:
A) The manual water replenishing valve itself cannot block the tap water due to failure, so that the tap water can enter the heating system.
B) plate heat exchanger or waterway integrated system leaks.
Solution:
A) Remove the foreign matter on the sealing rubber of manual water replenishing valve or replace the sealing rubber.
B) Replace the plate heat exchanger or the whole waterway integrated system.
7. The heating temperature rises rapidly, but the radiator is not hot.
Fault phenomenon: the wall-hung boiler quickly reached the set temperature, but the radiator was not hot and the ambient temperature could not rise.
Reason for failure:
A) There is a lot of air in the heating system that has not been exhausted.
B) The heating system is blocked, resulting in slow water circulation.
C) Many distributors are only opened a little, and the water flow is very slow.
D) The heating system is too big and the pump power is not enough.
E) water pump impeller is damaged.
F) controller output water pump voltage is abnormal.
G) unreasonable adjustment of power gear of water pump.
H) The bypass valve is not reset.
Solution:
A) Vent the air in the system.
B) Clean the heating system filter.
C) reasonably open the distributor.
D) add a water pump to increase the circulating force.
E) Replace the impeller of the water pump or replace the water pump.
F) replace the controller.
G) Adjust the water pump to a reasonable gear.
H) Reset the bypass valve.
8. The heating system is normal, but some radiators are not hot.
Fault symptoms: other radiators are normal, one or two radiators are not hot or one or two radiators are not hot.
Cause of failure: The opening of radiator distributor that is not hot is too small or there is air.
Solution: Open the opening of the distributor or remove the air from the radiator.
9. The heating system is operating normally, but the ambient temperature cannot rise.
Fault phenomenon: the water temperature of the heating system rises and the standby time is normal, and the radiator temperature is basically normal, but the room temperature is not high, which can not achieve the heating effect.
Reason for failure:
A) The power of the selected model is too small to match the large heating area.
B) The number of heater groups selected is too small, and the heating area does not match (the standard heat dissipation of each cast iron 760 standard part is 130W).
C) The radiator is seriously fouled.
D) The gap between pipes in the floor heating system is too large.
E) The bypass valve of waterway integrated system has not been reset.
Solution:
A) replace the high-power wall-hung boiler.
B) replace the large radiator.
C) Clean and remove the scale of the whole system or replace the radiator.
D) only increase the flow rate of water.
E) Reset or replace the bypass valve.
10, heating is normal, but hot water does not come out or cold water comes out.
Fault symptom: the heating state is normal, but it does not ignite or the hot water temperature is not hot when switching to the hot water state.
Reason for failure:
A) Turn on the hot water faucet when it is heated, but the running light does not work, which is caused by the hot water water flow switch fault.
B) In summer, when the heating is turned off, turn on the hot water tap and cold water will come out, indicating that the hot water water flow switch is out of order or the heating water flow switch is out of order.
C) The running light is on, but no hot water comes out. First, touch the surface of the heating pipe. If it is warm, the three-way valve cannot turn to hot water. The three-way valve is normal. If there is no heat exchange in the board exchange, the touch panel is changed on both sides. If one side is hot and the other side is cold, the plate exchange is damaged.
D) When no hot water is produced during the trial operation, the tap water and hot water connectors are connected reversely, and the flow switch does not act, resulting in no hot water.
Solution:
A) Replace the hot water water flow switch.
B) If the heating water flow switch fails, replace the heating water flow switch; If the hot water water flow switch fails, replace the hot water water flow switch.
C) When the three-way valve fails, replace the three-way valve; Board replacement fault replacement board replacement.
1 1. The hot water is used normally, but it cannot be heated when it is switched to the heating state.
Fault symptom: the domestic water heater is normal, but it cannot enter the heating state.
Reason for failure:
A) When the distributor is closed, the pipeline water shortage fault will be displayed.
B) Excessive air remains in wall-hung boilers and heating pipes.
C) The three-way valve is only in hot water state.
D) There are a lot of foreign bodies in the backwater filter, which hinders the heating water circulation.
E) The heating pipe is blocked and the heating water cannot be circulated.
Solution:
A) open the distributor.
B) exhaust air.
C) If the hot water flow switch contacts are always closed, replace the hot water flow switch; If the heating is always off due to the fault of the three-way valve, please replace it.
D) Remove the filter and clean the return water filter element.
E) clean the heating pipe.
12, excessive noise.
Fault phenomenon:
A) There is a roar in the wall-hung boiler when the ignition is started.
B) excessive noise caused by ignition delay.
C) excessive noise during combustion.
D) excessive noise of boiling water during heating.
E) the pump is too noisy.
F) The machine vibrates during operation.
Reason for failure:
A) caused by excessive gas during initial ignition.
B) The distance between the ignition pins is too large or too small, which leads to irregular striking of the ignition pins. Or the fault caused by the poor pulse igniter itself.
C) Because the bending length and quantity of the flue do not conform to the regulations (two 3m bends); And the air tightness of the exhaust pipe is damaged, which absorbs waste gas and produces noise; Gas pressure is too high; The maximum current of proportional valve is too large.
D) When the heated water is heated to a higher temperature in the combustion heat exchanger, water boiling noise will occur. This noise is caused by poor water quality or poor welding of the fins of the main heat exchanger.
E) there is air in the pipeline.
F) Poor connection of exhaust pipe or improper opening position of exhaust pipe.
G) the exhaust pipe is connected to the public flue.
H) gas pressure is too high.
I) unbalanced fans generate vibration.
Solution:
A) If the gas pressure is too high, adjust the gas pressure; If the gas valve is a proportional valve, the proportion will be reduced. The ignition current of the valve, if the gas valve is a segmented valve, adjust the small fire regulator to reduce the small fire and gas flow.
B) Adjust the ignition pin distance or replace the pulse generator.
C) Correct the unreasonable installation of chimneys; If the chimney leaks, seal it with tin foil or replace it.
D) improve the water quality or replace the heat exchanger.
E) Vent the air in the system.
F) Move the flue pipe from the public flue to the outside.
G) Turn down the gas pressure or gas.
H) Adjust the soft connection point of the fan to make it balanced.
13, the constant temperature time of domestic hot water is too long or cannot be constant.
Fault phenomenon:
A) Water is hot and cold, so it can't be constant.
B) the water temperature is too high.
C) It takes more than three minutes to keep the water temperature constant.
Reason for failure:
A) Water temperature fluctuates due to unstable water flow or air pressure.
B) The water temperature is too high because the water flow is too small.
C) Due to poor contact between water quality and inlet water temperature probe, the water flow sensor rotates unevenly or the water flow is small.
Solution:
A) Add water flow regulator and gas regulator.
B) Install a pipeline pump at the tap water inlet to increase the water flow as much as possible.
C) Clean the water flow sensor or make the inlet water temperature probe in good contact with the copper tube wall. Room 9 18, 9th floor, Langfang Meishuo Jewelry Deyi Building.