JUNKERS WR11-2 heater Failure, pilot light goes out due to obstruction of the gas tube.

ID: 157780

Description:

Steps:

1. Problem: The heater's pilot light goes out, unintentionally every few days, or the hot water tap quits.
2. Cause: Obstruction of the gas tube, to the pilot light. In my case it is due to the accumulation of dust and lint, as I have the dryer next to the heater, there is always fabric dust floating in the environment 'this fault' repeats itself every several months, so for me it is not a fault, it is a maintenance that I carry out every 6 or 8 months.
3. Dismantle and clean, I will explain absolutely everything step by step so that it can be applied to the same or similar heaters.

4. Junkers WR 11-2 heater (this model is no longer manufactured but the model that replaced it is), this one has already been used for 8 years and is in perfect condition, well-maintained devices last for many years.

5. One of the symptoms of tube obstruction is that the pilot light tends to turn orange or is somewhat higher than normal, 'it lacks strength'.
6. 1st Step: close the gas cock.

7. The heater cover has 2 Philips (Star) screws at the bottom, on both sides.

8. Right side screw.

9. The gas flow regulation button must be placed centered in the opening to be able to remove the casing.
10. The flow regulating button comes out by pulling it from the front.

11. Photo 1: Button removed.
12. Photo 2: The casing is removed by pulling on it, raising it.
13. Photo 3: With the casing at an angle of approximately 30 to 35º, the casing is raised, unhooking it from the upper part.

14. Lid raised to unhook it.
15. Example of one of the hooks at the top.
16. Heater, overall view.

17. Detailed photo of the pilot light (flame) tube, which aims at the thermocouple pin, if it is not directly touched by the pilot flame, it does not have the appropriate temperature and forces the heater to turn off.

18. Checking the inside of the heater, a greenish powder is observed, this is a symptom of a slight water leak, it can be like this for even a year, we just have to keep in mind that in the future we may have a failure.

19. To remove the tube that has obstruction problems, we must remove the clip or clip that holds it at the top.

20. Once the clip has been removed, the tube is fitted into its hole at the top, and hooked into a U-shaped elastic clamp at the bottom. In this part, we unhook the tube with the help of a thin screwdriver using light pressure.

21. We raise the tube and remove it from its housing at the top.

22. Now we will proceed with a brush to clean all the remaining dust and green dust.

23. We must clean everywhere we see dust, both in the mechanism and in the upper part, since accumulated dust can end up falling and accumulating in the lower part where it could wind up in the pilot light tube.
24. The next step, cleaning the thermocouple stem with a metal brush; is advisable but not essential, since this fault is really the problem of a clogged tube.

25. 1st, gently clean the stem with the metal brush.
26. 2nd, Clean with a brush to remove any loose wires from the (wire) brush.

27. mage of the clean thermocouple.

28. THIS IS THE PROBLEM, A SEMI-PLUG OF DUST AND TEXTILE LINT, IN THE GAS TUBE OF THE PILOT FLAME.
29. We see it is semi-clogged at the outlet end and at the base.

30. We can carry out the 1st part of the cleaning with alcohol and ear swabs.

31. Since we have a spring at the gas outlet end, we cannot insert the swab, so the 2nd part of the cleaning will be done in the sink, running water through the tube.
32. Once clean, we dry it, we can shake it and blow through it to remove all the water inside.

33. To replace the tube, we will reverse our actions
34. 1st we will hook it from the top.

35. 2º We place it in front of the U at the bottom and with a little pressure it stays hooked.

36. We insert the clip that holds it at the top.

37. And now comes the fine adjustment, the tube cannot be very close to the 'jerk' gas outlet screw nor too far apart, the correct thing is a separation of about 3 to 4 mm.
38. Explanatory VIDEO in case you have to clean the gas outlet jet:

39. Everything's ready, the next step is to turn on the heater to see if the repair has been correct, we open the gas valve.

40. We press the power button; in this old model, a torrent of sparks jump out that should light the pilot light without problems.

41. The pilot flame must come out HORIZONTAL AND BLUE. If it does not come out horizontally and focused directly on the thermocouple, it will not heat it properly and when you gradually release the ignition button, the flame will go out.
42. (if the flame was orange it would indicate poor combustion).

43. This step is only illustrative, I have measured the approximate height of the flame and it is about 6 to 7 mm. If it were smaller or higher, we would have to slightly vary the distance between the tube and the jet (STEP 24).

44. We will open a hot water tap and see how the gas flow opens, turning on the entire burner and turning it off when we close the tap.

45. With everything checked, we proceed to place the cover, in reverse order of how we removed it, we see above on the chassis, the 2 hooks.

46. Hooked at the top, we lower the cover. BE CAREFUL WITH THE POSITION OF THE GAS REGULATION BUTTON, it must coincide with the opening. (centered, remember?)

47. The water flow regulating knob has an internal notch, we must locate which side it is on, since it can only be placed by inserting that notch correctly.

48. Once the knob is inserted, facing the notch, with slight pressure we fit it in place.
49. We reopen the gas valve to turn on the heater.

50. We press the ignition button, we'll hear the torrent of sparks, when the flame lights we can slightly release the control, we continue holding it down for a few seconds then release it slowly, the flame should remain on.
51. We will set the gas flow button, to the position where we originally had it.
52. REPAIR OR PREVENTIVE MAINTENANCE, COMPLETED.