[Solved] Junkers ZW 14-2DVAE23S5300 - C6 error, relay replacement + error codes

Hello,

I have a seven-year combi oven with a closed combustion chamber. This morning he let me down for the first time Error C6 has appeared. After the reset, only the circulation pump started and after a few dozen seconds C6 again.
I read a few topics in the forum and started checking according to other users' suggestions.

I started by dismantling and checking the pressure switch - functional. I noticed that the fan does not start - no supply voltage at its terminals and at the output from the motherboard. Disassembly and measurement of the 24VDC relay, described on the board as RY1 (functional coil, damaged working contacts) - replacement for a new one - the furnace works

I used the replacement because I don't have the original yet. I enclose a photo, maybe someone will need it:
20171029_1..636.jpg Download (4.4 MB) 20171029_2..844.jpg Download (1.85 MB) 20171029_2..134.jpg Download (2.23 MB)



I also attach the error codes (they refer to the Junkers Eurostar model). They are sought after in the forum, so they may be helpful:

A7 Open circuit or short circuit in the DHW temperature sensor circuit Check the DHW temperature sensor and connecting cable

AC There is no electrical connection between the slide-in module and the Heatronic module. Check the cable connecting the modules.

Ad Damaged cylinder temperature sensor. Check for an open or short in the sensor circuit or sensor connection cable.

b1 Coding plug. Insert the coding plug correctly and replace if necessary.

C1 The pressure switch has opened during operation. Check pressure switch and connecting pipes.

C4 The pressure switch does not open at rest. Check pressure switch.

C6 Pressure switch does not close. Check pressure switch, drainage mechanism and connecting pipes.

CC Break in the outside temperature sensor in the controller

TA Check the outside temperature sensor and connecting cable.

d1 No voltage feedback signal from LSM. Check wiring with LSM. The floor heating limiter has tripped.

E0 Internal error on the motherboard. Check electrical contacts, ignition leads, replace main board if necessary.

E2 Open or short circuit in the flow temperature sensor circuit. Check the NTC flow temperature sensor and connecting cable.

E9 Safety temperature limiter (STB) has tripped. Check the NTC flow temperature sensor, pump overrun, fuse on the main board, STB, vent the boiler.

EA No ionization current. Check that the gas valve is open, gas connection pressure, network connection, ignition electrode and cable, ionization electrode with cable, flue gas discharge and CO2 concentration.

F7 Incorrect ionization signal. Check that the ionization electrode and cable are not cracked or cut, check for moisture in the Heatronic control box.

FA Ionizing current after switching off the regulator. Check the gas valve wiring and gas valve.

This is not a replacement for this relay!
Your reasoning even a 30kW motor contactor would be a replacement for this relay.

Maybe I spoke wrongly, but without exaggeration buddy. The substituted relay is for the same supply voltage and has the same load capacity of the working contacts.

Despite the search, I haven't been able to buy the original yet.

For me, the most important thing is that the stove works correctly

For other leg insertions. Do you recommend making spiders on the disc? Universal relay available in most electronics stores. Even on the website.

I do not recommend creating cobwebs on the disc and I gave photo info on a different leg spacing. When I have the opportunity, I will probably buy relays and mount the original.

Writing on the forum, I wanted to share the details of the failure of my furnace rather than promote the fancy assembly of replacements. The topic was created rather for people who will find themselves in a similar situation as me, i.e. the failure of the stove on a cold Sunday.

I would like to draw your attention to the fact that a common reason for the C6 error may be a faulty relay. Perhaps someone will encounter a similar failure, so they will be able to start the diagnosis by checking this device.

I informed you that I am providing an ad hoc solution to the problem. You have misread the idea of adding a topic to this topic.

As I read your post, I remembered the disc after being repaired by one car electronics.

Sorry.

But gas control elements if it's only 1: 1

Relay link that you should use

I'll take it to heart
Of course, you probably have a lot of experience in this topic and I should not argue with you in this matter.

Thank you for your comments and links.

Thanks for the error codes, I have an old Junkers stove, still from Germany, and it was after 25 years that error d1 appeared. Anyone know what LSM is? Any poll?

D1 damaged return sensor