Causes and solutions for common problems of wall-hung boilers

　　1, insufficient pressure failure

　　 Failure phenomenon: The water pump does not rotate, the controller alarms, and the failure code displayed on the display is insufficient pressure.

  cause of issue:

　　A) The pipeline lacks water, and the pressure gauge shows that the pipeline has insufficient water pressure.

　　B) Pressure switch failure.

　　C) There is a large amount of air in the piping system.

  Solution:

　　A) The pipeline lacks water to make up water; if the pipeline leaks, find ways to stop the leak.

　　B) Check with a multimeter. If the pressure switch is not turned on, replace the pressure switch; if the contact is poor, reconnect it; if the circuit is broken, replace the wire; if the wrong terminal is inserted, press the correct connection.

　　C) Exhaust the piping system.

　　2, pipeline water shortage failure

　?、?Failure phenomenon: the water pump does not run, the fan does not run, the controller alarms, and the fault code displayed on the display is that the pipeline lacks water.

  cause of issue:

　　A) The pump power cord is off

　　B) The pump does not lock up for a long time.

  Solution:

　　A) Use a multimeter to check whether the output power of the pump is normal and whether the contact is good. If the controller has no voltage output, it means the controller is faulty. Replace the controller; if the controller has voltage output and the water pump is out of power, the connector has fallen off, the contact is poor or the wire is disconnected; if it falls off, re-contact, and if the contact is poor, make it contact. Good, replace the wire when the wire is disconnected.

b) If there is voltage input to the water pump, but the water pump does not rotate, the water pump may be locked, unscrew the flat screw on the water pump, use a flat screwdriver to turn the water pump shaft, the water pump rotor can be rotated to return to normal; if the water pump does not If the pump is locked and a multimeter is used to detect the open circuit or short circuit of the water pump, the water pump is burned out. Replace the water pump.

　　② Failure phenomenon The water pump is running, the fan is not running, the controller alarms, and the display shows the pipeline lacking fault code.

  cause of issue:

　　A) The air in the water pump is not exhausted, causing the water pump to run idly.

　　B) The heating system distributor is not opened or the filter is blocked.

　　C) There is not exhausted air in the pipe.

　　D) The water flow switch is faulty.

　　E) The pressure difference generated by the differential pressure type pipe is not enough.

  Solution:

　　A) Unscrew the slotted copper screw on the end of the water pump, exhaust the air of the water pump, and restart.

　　B) If the heating system distributor is not open, open the distributor; if the filter is clogged, remove the filter, rinse it, and install it, make up water and exhaust, and restart.

　　C) If there is air in the pipe but not exhausted, exhaust the air and restart.

　　D) If the water flow switch fails, use a multimeter to check whether there is a switch signal output during operation. If there is a signal output, that is, the water flow switch is turned on, it may be that the connector is not well connected or the wire is disconnected, then connect the connector or replace the wire; if the wire and the connector are intact, the controller is faulty, replace the controller . If there is no signal output, it means that the water flow switch is stuck or the water circuit is blocked; if the water flow switch is stuck, remove the water flow switch to rinse and reinstall it; and replenish water. Exhaust and restart again; waterway blockage is handled according to method b.

　　E) Install a distributor (switch) at the heating water outlet, just turn off the distributor a little bit smaller.

　　3, fan wind pressure failure

　?、?Failure phenomenon: The fan does not run or runs slowly, the controller alarms, and the display shows the fan air pressure failure code.

  cause of issue:

　　A) The fan is stuck or burned out;

　　B) Poor contact of the connector

　　C) Controller failure

　　D) The capacitor is damaged

　　E) The electric power of the city is too low.

  Solution:

　　A) Check the fan with a multimeter, replace the fan when the circuit breaks, or replace the fan if it is stuck.

　　B) The connector is in poor contact and reconnect it.

　　C) The controller is faulty and replace the controller.

　　D) If the fan impeller can be started by pulling it by hand, the capacitor is damaged. Replace the capacitor.

　　E) Install a voltage regulator to increase the mains voltage to 220V.

　　②Fault phenomenon: The fan is running normally, the controller does not ignite, the main controller gives an alarm, and the display shows the fault code as fan air pressure failure.

  cause of issue:

　　A) Short circuit of wind pressure switch

　　B) The wind pressure switch is not closed.

　　C) Poor contact of the connector.

　　D) The suction and exhaust ports are blocked.

　　E) Controller failure.

  Solution:

　　A) Check with a multimeter. If the wind pressure switch is closed before the fan starts, replace the work or adjust the wind pressure switch.

　　B) If it is normal before the fan is started, but does not close after the fan is started, the air pressure switch can be adjusted. If the problem cannot be solved after adjustment, replace the air pressure switch. ; Also check whether the venturi tube or the wind pressure tube is blocked.

　　C) If the connector is in poor contact, reconnect it.

　　D) If all the previous faults are eliminated, check whether the suction and exhaust are smooth or blocked; if the suction and exhaust are not smooth, clean the flue; if it is blocked, clean up.

　　E) The faults of a, b, c, d have been eliminated, check whether the pulse igniter connector is in good contact, and whether the main controller has 4.5V power

　　Pressure output. If the contact is poor, the plug is good; if there is 4.5V output, replace the pulse igniter; if there is no 4.5V output, replace the main controller.

　　 4. Ignition failure failure

　　 Failure phenomenon: The pulse igniter ignites normally, but does not ignite, the main controller alarms, and the display screen displays the failure code of ignition.

  cause of issue:

　　A) The ignition pin insulation porcelain is damaged or the metal pin is loose, resulting in weak ignition spark.

　　B) The power supply of the gas valve is abnormal, causing the solenoid valve to fail to open.

　　C) The adjustment of the ignition current of the proportional valve is unreasonable.

　　D) The flow adjustment of the small flame of the sectional valve is unreasonable.

　　E) Foreign matter accumulates on the gas valve valve, which makes it poorly activated.

　　F) The proportional valve rubber tympanic membrane is defective.

　　G) Broken solenoid valve coil (short circuit or open circuit).

　　H) The gas pressure is too high or too low.

　　I) The high and low speed lines of the two-speed fan are connected back.

　　J) The relevant parameters of the ignition needle are incorrect.

  Solution:

　　A) Replace the ignition needle.

　　B) Replace the main controller.

　　C) Adjust reasonable ignition current of proportional valve.

　　D) Adjust the gas flow rate of the small fire with reasonable segmentation valve.

　　E) Remove foreign matter from the gas valve.

　　F) Replace the gas valve.

　　G) Replace the solenoid valve.

　　H) Adjust the gas pressure to the rated pressure.

　　I) Correctly connect the high and low speed wires of the two-speed fan.

　　J) If the distance between the ignition needles is too large or too small, adjust it to 3～4mm; if the direction of the ignition needle is severely skewed, adjust or replace the ignition needle. If the distance between the ignition needle and the burner is too far, the adjustment is reasonable.

　　 5. Unexpected flameout failure

　　Fault phenomenon: after ignition, the main controller will alarm, and the display will display the accidental flameout fault code.

  cause of issue:

　　A) Carbon deposits on the flame sensor needle.

　　B) The connection of the flame sensor needle is poor.

　　C) The suction and exhaust ports are blocked or the flue air inlet is not extended outside the wall.

　　D) The wind is too strong outside.

　　E) The supplied gas pressure is abnormal, too high or too low.

　　F) Controller failure.

　　G) The flame sensor needle does not touch the flame.

　　H) The flue is not installed properly.

　　I) Put the intake and exhaust pipes into the public flue.

　　J) The grounding wire is off or disconnected.

  Solution:

　　A) Clean up the carbon deposits on the flame sensor.

　　B) The flame sensor needle cable is well connected.

　　C) Clean the suction and exhaust ports to make the suction and exhaust smooth.

　　D) Change the position or direction of suction and exhaust.

　　E) Adjust the gas pressure to the rated supply pressure.

　　F) Replace the controller.

　　G) Adjust the flame sensor needle to a position where it can touch the flame in large or small fires. The best is the junction of the inner and outer flames of the flame.

　　H) It is forbidden to connect the intake and exhaust flue to the public flue and move it outside.

　　I) If it is normal after removing the smoke tube, it means that the smoke tube is not connected properly. Reconnect the smoke tube.

　　6, overheating failure

　　Fault phenomenon: The wall-hung boiler turns off, the main controller alarms, and the fault display shows the fault code of overheating and dry burning.

  cause of issue:

　　A) The heating distributor is closed, causing the water temperature in the main heat exchanger to rise rapidly, and the hot water temperature exceeds 90°C, causing the bypass valve to open.

　　B) The heating pipeline is blocked, which slows down the water circulation, the water temperature rises rapidly, and the hot water temperature exceeds 90°C.

　　C) The overheating protection thermostat is defective and should be normally closed instead of normally closed.

d) The flow direction switching function of the three-way valve is disordered (three-way valve type), which may be caused by the misalignment of the connection line or the misalignment of the ball assembly and the poor rotation of the ball, which causes the hot water to enter the plate through the three-way valve and perform a small cycle during heating. , The water temperature rises sharply.

　　E) Controller failure.

　　F) The distributor (switch) is installed in the opposite direction.

　　G) The filter is clogged.

  Solution:

　　A) Turn on the heating distributor.

　　B) Dredge the heating pipes.

　　C) Replace the overheat protection thermostat.

　　D) If the connection line is misaligned, correct the connection; reassemble the three-way valve ball if the ball is assembled incorrectly; replace the three-way valve if the ball rotates poorly.

　　E) Replace the controller.

　　F) Reassemble the distributor (switch) to make it in the correct direction.

　　G) Clean the filter.

    Warm reminder: To be able to master various wall-hung boiler repair methods, you must first master the basic principles and working procedures of the wall-hung boiler work, installation requirements, use and debugging methods and maintenance knowledge; secondly, you must have a wealth of practical experience in order to Various failure phenomena are analyzed and judged, and the failure is eliminated; once again, a strong hands-on ability is necessary to correctly disassemble and assemble various components.

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