Ariston Genus One System: Addressing Gas Boiler Errors 501,504,309,5p3 After Replacing Parts

Hello,
my gas boiler makes me crazy...
one day everything is fine, another day flame lifts, no flame detected 501,504, error codes appear intermittently.
I have replaced the ignition and ionizing electrode, after successful automatic calibration the boiler works two days fine.
Guess what happened next, again 501,504,5P3 and also 309- gas relay check failure, so, pcb out and have taken a look at the relay in the pcb board, there is one Omron relay, I checked the relay out of the board, relay was ok, nevermind, I replaced it with a new one (was already ordered). Also, two filter capacitors have been replaced (they have half capacity like nominal)
Please, take a look at this pcb, what else I should check...
Boiler works 3 years fine, no problem, until now...
Thank you in advance

Hi. I also have the same problem. Boiler Ariston One Altea One net: Fault 309. Gas boiler worked 2 years without problem but now started this problem. And all master can't repair. Maybe someone has advice?
Thanks

Hello,
mine worked 3 years without problems... later errors 501, 504, 5P6, 5P3... and also sometimes 309, most time RESET solved problem, but finally appeared error 303 and this was the end.
I have solved it
I am not sure if you have same main board..., but it could be same,
on picture are marked ICs, those were resoldered and after controlled under microscope,
boiler came back to life !

309 may pop out when a flame is detected despite the gas valve being closed.
This is probably what the ionization electrode does, so I would look for a problem there.
Well, unless the valve is off and you actually have a flame.

I also have this boiler, fortunately with an extended warranty.
They have already exchanged the motherboard 2x.

I found something that is probably the real reason for 309 error(gas relay check failure), also it have to do with bad ignition due wrong gas dosing..., only resoldering mcu, cpu and other ic´s is not enought as i posted earlier, i was wrong, sorry for that.., any way, fixing 309,303 errors is possible,
Replacing smd capacitor marked in yellow colour with new one, i do not know exact value (any wiring diagram), but i replaced with 22nF, big one for 250vac and .... it seams to be ok, boiler igniting well and since that, no error codes, any.
Capacitor is connectet in parallel to gas valve selenoid, maybe timing capcitor?

aronmiso wrote:

Two filter capacitors were also replaced (they have half the capacity as nominal)

can you know which?

This marked capacitor has half capacity, I have replaced

@aronmiso
All it's ok now?
I have the same problem: 5P3, 5P6, 501 and 309
Thanks a lot!

HI,
I have the 5P6 Error.
I try to put the Boiler into "Summer" operation (turning off the central heating). This allows me to have hot water in the shower.
So I'm wondering if there could be some problem with the Siphon?

Has anyone tried to clean the Siphon?

thanks

I solved the problem just by replacing the electronic board.

Hi,
Can you give us the values of capacitors which you replaced?
Best regards.

aronmiso wrote:

I found something that is probably the real reason for 309 error(gas relay check failure), also it has to do with bad ignition due to wrong gas dosing..., only resoldering mcu, cpu and other ic´s is not enough as I posted earlier, I was wrong, sorry for that.., anyway, fixing 309,303 errors is possible, Replacing smd capacitor marked in yellow colour with new one, I do not know exact value (any wiring diagram), but I replaced with 22nF, big one for 250vac and .... it seems to be ok, boiler igniting well and since that, no error codes, any. Capacitor is connected in parallel to gas valve solenoid, maybe timing capacitor?

UPDATE:
Use 1nF capacitor, flame is stable and no flame lifts anymore! after two weeks testing I have 0 error codes.

Hello, what voltage is this 1nF SMD capacitor for?

Hello.
I have the same model only Chaffotaux Mira Advance 25 - the equivalent of the Ariston Genus One
After exactly 3 years: /
I have the same problem 501, 504 5P3 5P6 sometimes 303 and 309
The album looks the same ... they want from PLN 1,200 to PLN 1,400 for the new one.
Repair with a guarantee for 12 months PLN 500 ...

The solution is these ICs ???
Do you need to replace them or fly through the cold February ???
Capacitors also on 1nF?

Thanks in advance for the hints.
MF

I replaced the capacitor and didn't change a thing..I've noticed the resistors around the relay are getting very hot

Also, this LM317M is getting real hot which is an adjustable voltage regulator the voltage from Vin to ground shows 28 V from Vout to ground fluctuates from 17V to 22V I don't know if this is normal. One more thing I noticed is getting hot but not that hot is this that FB pin is connected to one of the optocoupler pins

I've desoldered and checked all this marked with red they look good

The one with yellow gives continuity when tested with a multimeter with the black probe on ground and the red one to the positive side of the capacitor with a 30 ohm reading..I think this is somehow normal because there are two 15 ohm resistors in series from positive to negative. When desoldered and measured this cap gives 100 uF exactly as is written on. The relay seems to work fine when tested with a 12V I can hear it clicking.(too bad I forgot to measure the resistance of the coil inside) Another thing I've noticed is that the spark sound is very low...before the problem with the boiler I could hear it very clear..now is very faint.. Maybe someone with more electronic background can help ..I'm just a guy with a soldering iron and a multimeter.

heeler11 wrote:

Hello, what voltage is this 1nF SMD capacitor for?

Use capacitor for 24 VDC, or higher, there is max 24 V DC
I have replaced smd cap with big one 1nF 250V, it works well

Added after 1 [hours] 19 [minutes]:

maciejfulara wrote:

Hello.
I have the same model only Chaffotaux Mira Advance 25 - the equivalent of the Ariston Genus One
After exactly 3 years: /
I have the same problem 501, 504 5P3 5P6 sometimes 303 and 309
The album looks the same ... they want from PLN 1,200 to PLN 1,400 for the new one.
Repair with a guarantee for 12 months PLN 500 ...

The solution is these ICs ???
Do you need to replace them or fly through the cold February ???
Capacitors also on 1nF?

Thanks in advance for the hints.
MF

Replace SMD capacitor : https://www.elektroda.com/rtvforum/topic3842205.html#19944123

Added after 15 [minutes]:

meriusmerius wrote:

I replace the capacitor and didn't change a thing..I've noticed the resistors around the relay are getting very hot

this overheating is present after you replace SMD capacitor? and is boiler working even with this overheating resistors?
what error code pop up on boiler before you made any change on pcb?
I suggest to check all connected accessories to PCB, like gas valve - measure solenoid resistance, temperature sensors....

aronmiso wrote:

heeler11 wrote:

Hello, what voltage is this 1nF SMD capacitor for?

Use capacitor for 24 VDC, or higher, there is max 24 V DC
I have replaced smd cap with big one 1nF 250V, it works well

Added after 1 [hours] 19 [minutes]:

maciejfulara wrote:

Hello.
I have the same model only Chaffotaux Mira Advance 25 - the equivalent of the Ariston Genus One
After exactly 3 years: /
I have the same problem 501, 504 5P3 5P6 sometimes 303 and 309
The album looks the same ... they want from PLN 1,200 to PLN 1,400 for the new one.
Repair with a guarantee for 12 months PLN 500 ...

The solution is these ICs ???
Do you need to replace them or fly through the cold February ???
Capacitors also on 1nF?

Thanks in advance for the hints.
MF

Replace SMD capacitor : https://www.elektroda.com/rtvforum/topic3842205.html#19944123

Added after 15 [minutes]:

meriusmerius wrote:

i replace the capacitor and didn't change a thing..i've noticed the resistors around the relay are getting very hot

this overheating is present after you replace SMD capacitor? and is boiler working even with this overheating resistors?
what error code pop up on boiler before you made any change on pcb?
I suggest to check all connected accessories to PCB, like gas valve - measure solenoid resistance, temperature sensors....

its still working with the same sp3 flame lift error..the overheating was present before and after the replacement of the smd capacitor..the solenoids from the gas valve have a 68Ohm and 24 Ohm.. https://www.youtube.com/watch?v=Dm_J10Sg2d4&t=20s i have the same gas valve as in this video..i'll try to find a bigger 1nF cap

Added after 6 [minutes]:

i can hear the gas valve working its like a heart beat sound and right before the error i can hear the rhythm fall and stops.. then the turbine fan goes on to clear the air from the burning room...(sorry for my primitive english)

Hello everyone,
I have an Alteas One with the same problem and it makes me crazy too. It works 2 or 3 hours and starts failing with 501, 5p3, 5p6, and sometimes 309 errors.
@meriusmerius - Looking at the pcb and your comments, I noticed the LM317 hot too, and it varies its output voltage, about 16 to 21 V, looking around it, it is fed by a 7824 regulator, one more thing I found not common is that its reference resistor is 0 ohm. May be a special way of using it? Could someone with a working good board confirm if it is ok the 0 ohm resistors?

Anyway, the LM317 seems to be for the orange connector T B Bus communication, this bus is two wires, for power supply and communication with Cube Room sensor or others, so that could make sense of the voltage variation, I have the Cube Room connected to it and it works ok.

Coming back to the failure, I measure the valve coil and it is 8.55 V, it varies a little bit with gas power needed. I have to calibrate many times till I found a time it works better.

@aronmiso - by the way, still working ok after cap replacement?
I will replace the smd capacitor in parallel with the coil and see how it goes.
Thanks!

@Gabriel_Ushuaia Hello, my boiler works wihout any errors since smd cap replacing, (also was replaced every aluminium capacitor on board - as prevention, but no one capacitor was bad! they have a little bit lower capacity like nominal).
I have measured voltage on LM 317 (or on TBUS connector), there is 15-21V, temperature in standby is 35°C, when flame on about 47, i can hold finger on it,
mentioned resistors are in stand by same as LM317, when flame is on, temperature is about 50°C, on touch are resistors hotter as LM, i think this is normal temperature for this components.

aronmiso wrote:

@gabrielushua Hello, my boiler works without any errors since smd cap replacing, (also was replaced every aluminium capacitor on board - as prevention, but no one capacitor was bad! they have a little bit lower capacity like nominal).
I have measured voltage on LM 317 (or on TBUS connector), there is 15-21V, temperature in standby is 35°C, when flame on about 47, i can hold finger on it,
mentioned resistors are in stand by same as LM317, when flame is on, temperature is about 50°C, on touch are resistors hotter as LM, i think this is normal temperature for this components.

Thanks @aronmiso, about LM317 let said it is ok, and not related to the problem.
About the flame problem, I added a 10nF parallel capacitor to the valve coil, (I did not removed the smd capacitor on the board) and it is working much better since yesterday, I get just two errors, and one is 309, ionizer detection error, so I'll be working on this, trying to get the schematic.
My guess is that some parts of the circuit could be getting electrical noise, and all those analog signals with slow change could need more capacitors too.
If someone does have the pcb schematic will be good
Thanks
Best regards

@gabrielushua "I have measured voltage on LM 317 (or on TBUS connector), there is 15-21V, " I've got the same readings
Can you confirm if you have these readings when the boiler is working without any errors?

I've desoldered all the electrolytic and ceramic capacitors, all the hot resistors, all the varistors; measured and resoldered everything back
got an error 503 (I think..was saying something about flame lift with gas valve closed; asked me to reset..3 times in a row I got the same error; display said too many resets).

unplugged the boiler for 2 minutes ..turned it on and for some reason so far everything is working fine.

I measured what you can see in the picture...I got those values when the boiler was burning and was wondering if this is normal..

When trying to measure the voltage between those two yellow marks with the boiler burning I could hear the gas valve truly opening
and the gas rushing in.

Hi,

I have been actively reading this topic, but did not have anything to add.

This series-failure is very-very common among Hungarian users as well, and nobody knows an exact solution on any of the forums.

I have a Genus One 24 system, and I have two boards already. 1st board was damaged in a power grid failure, but before that, we already experienced errors on a monthly/bi-weekly basis. After it was replaced the errors have gone with the 2nd panel.

After one year the 2nd panel started to have the errors on the same monthly/bi-weekly basis, and after another year, it had these errors several times a day. After that I put back the 1st board (I replaced the blown varistors and capacitors) and it worked for 3-4 months, and started to get worse and worse.

I tried to replace the capacitor near the valve - did not help.
Someone said reflowing the large SMD resistors near the connector helped - for me it didn't.
I desoldered and checked all caps with ESR cap meter - every piece was giving factory values.

I came here to comment one thing about the LM317 you are suspicious about:

That is normal to measure changing values on that. The boiler uses a protocol called eBUS. This protocol uses 2-wire connection which is responsible for both powering the external temp sensor, and communicating with it. It is (very briefly) communicating by changing supply voltages within a given range. This changing supply voltage is achieved by putting the LM317 into current-limiting mode. The 24V supplied by the LM7824 is going through the LM317 which is limiting the current. When the boiler/thermostat wants to say something, they short the supply voltage to ground through a resistor. As the current is limited, the supply voltage will drop, and the equipment detects this voltage drop (the dropped voltage is still way more than they require for operation).

So at least I could add this information to you, and I will stay tuned on your findings.

(There is a local electronic repair shop that says they can fix this specific panel, and they are giving warranty on it. Probably I will spend that 100Eur on it, and then I will try to backtrack what did they modify)

meriusmerius wrote:

@Gabriel_Ushuaia "I have measured voltage on LM 317 (or on TBUS connector), there is 15-21V, " i've got the same readings
Can you confirm if you have this readings when the boiler is working without any errors?

I've desolder all the electrolytic and ceramic capacitors ,all the hot rezistors ,all the varistors ;measured and resolder everything back
got an error 503 (i think..was saying something about flame lift with gas valve closed ;asked me to reset..3 times in a row i got the same error ;display said to many resets).

I've

unpluged the boiler for 2 minutes ..turn it on and for some reason so far everything is working fine .

I measured what you can see in the picture...i got those value when the boiler was burning and was wondering if this is normal..

When trying to measure the voltage betwen those two yellow marks with the boiler burning I could hear the gas valve truly opening
and the gas rushing in.

Hello, here is my mesurements when it is working, the modulating valve coil is in between the transistor collector (12.44V) and the resistor (3.81V) . So coil gets 12.44 - 3.81 = 8.63V. This is getting by the calibration process, it start increassing the coil voltage from about 7 V till the gas burns, in my case it takes 6 or 7 trys when calibrates and reach the 8.6 or 8.7V, I think the controller memorizes this state for working then, and the feedback circuit takes care of the 3.81V, the coil current (about 125mA) flows throw the two 15R0 resistors in series, and generates the 3.81V for the feedback, by the way you said the ressistors get hot and in my case too, it is because they are discipating 1/4 W each one.
I wonder if it toomuch hot and get out of tolerance and make lowering the coil current by misstake, that is a possibility of the problems, I leave it the plastic cover out and panel open and seems to work better, may be it werk not so hot, lets see.

Thanks for the comments to everyone
Regards

Added after 24 [minutes]:

razorbenke92 wrote:

Hi,

I have been actively reading this topic, but did not had anything to add.

This series-failure is very-very common among Hungarian users as well, and nobody knows an exact solution on any of the forums.

I have a Genus One 24 system, and I have two boards already. 1st board was damaged in a power grid failure, but before that, we already experienced errors on a monthly/bi-weekly basis. After it was replaced the errors have gone with the 2nd panel.

After one year the 2nd panel started to have the errors on the same monthly/bi-weekly basis, and after another year, it had these errors several times a day. After that I put back the 1st board (I replaced the blown varistors and capacitors) and it worked for 3-4 month, and started to get worse and worse.

I tried to replace the capacitor near the valve - did not help.
Someone said reflowing the large SMD resistors near the connector helped - for me it didn't.
I desoldered and checked all caps with ESR cap meter - every piece was giving factory values.

I came here to comment one thing about the LM317 you are suspicious about:

That is normal to measure changing values on that. The boiler uses a protocol called eBUS. This protocoll uses 2-wire connection which is responsible for both powering the external temp sensor, and communicating with it. It is (very briefly) communicating by changing supply voltages within a given range. This changing supply voltage is achieved by putting the LM317 into current-limiting mode. The 24V supplied by the LM7824 is going through the LM317 which is limiting the current. When the boiler/thermostat wants to say something, they short the supply voltage to ground through a resistor. As the current is limited, the supply voltage will drop, and the equipments detect this voltage drop (the dropped voltage is still way more than they require for operation).

So at least I could add this information to you, and I will stay tuned on your findings.

(There is a local electronic repair shop that says they can fix this specific panel, and they are giving warranty on it. Probably I will spend that 100Eur on it, and then I will try to backtrack what did they modify)

Hi, razor, thanks for your comments about LM317, I saw same too, it is normal working for comunication protocol, I have cube sensor connected to it, so no problems with it.
I leave it the coil parallel capacitor added and now I´ll be testing with the cover open. Rigth now I get more 309 error (about ionizzation detection) than 5P3 (flame out)
Regards

I have the very same problem (and changing the capacitor didn't fix it for me). When I slightly pull the board up at the point of the X3 pinout by a piece of plastic, the flame is gone. So I suppose it's a cold joint somewhere. But I didn't find any on the up side. Has anyone tried to reflow the whole board?

Currently, I suspect some of the through-PCB joints to be broken. Has anyone investigated that yet?

FWIW, when I remove the board and play with it so that it cools down, and put it back, it works for a day. Perhaps until it warms up and slightly twists itself. I think it supports the cold joint theory.

jirislaby wrote:

I have the very same problem (and changing the capacitor didn't fix it for me). When I slightly pull the board up at the point of the X3 pinout by a piece of plastic, the flame is gone. So I suppose it's a cold joint somewhere. But I didn't find any on the up side. Has anyone tried to reflow the whole board?

Currently, I suspect some of the through-PCB joints to be broken. Has anyone investigated that yet?

FWIW, when I remove the board and play with it so that it cools down, and put it back, it works for a day. Perhaps until it warms up and slightly twists itself. I think it supports the cold joint theory.

I have the same opinion with my board, after replacing mentioned smd capacitor (and all aluminium capacitors), I have reflowed ICs and inspected PCB under microscope (nothing found), problem disappears, but now, 1 year later, I have again from time to time flame lifts. I will send my board to rtg scanner, it is the last thing that I could do to find out what is really the problem on this pcb.

For me the problem is that the Ariston gas stove works ok for a few days and then there is a massacre and for the next few days only errors and only resetting helps for a while ...

So I measured most of the joints in the left bottom corner of the desk and I found exactly nothing. Maybe because I pushed some of the cold joints and it is fixed for 3 weeks now. Note that it's the circuit which controls the valves. Anyway, I drew a schema of that while checking the board. I double checked most of the connections, so it should be more or less correct. I will update it once I find a mistake, if at all.

It also includes some voltage measurements.

Everything is at:
https://drive.google.com/drive/u/0/folders/1GTyb_TC5dc0Ab5QAxp_qsF82PSjE7Cl5

Hi,
I have a problem with 5P6 error and 5P3 no flame. Replaced the ignition electrode.
I hope that's it.

best regards
Fatmir

Hello everyone. I'm from the Czech Republic. I will describe my observations here. I am trying to repair a GAL-EVO2 HE 740190026408 board (Ariston HS Premium 24 EU2) which has the same problem. I checked the capacitors and relays and found no problem. Unfortunately, I still haven't found a diagram of connecting the board to the boiler, but it seems to me that the solenoid valve is powered by 230V rectified voltage on this board. This means no flame adjustment. I think someone needs to look at it through an oscilloscope to find out what happens voltage across this solenoid when an unstable flame occurs.

I have noticed dependence. When it's cold outside (a little below 0) the gas boiler displays errors and fires hard, but when the temperature outside is around 10 degrees Celsius, everything works great. Do you also have the same?