Vokera Mynute 14e problem

[Michael29068]

Hi, I have a Vokera Mynute 14e which runs the circulating pump and fan for approx 1 second and then goes to lockout (red led flashing). I have replaced the ntc thermistor and tried a new pcb but still cannot get the boiler to run. Any suggestions. Thanks.

 

[mickie]

ring the manufacturers up, they'll ask you for your gs number and they'll run through the problem with you.. if you still dont understand what to do after they explain get someone else out..

 

[tamz]

Phone a heating guy. It will not be expensive, certainly cheaper than the pcb you bought for nothing.

 

[diamondgas]

1 second then lockout with a new PCB? ....... That does not compute! Have you checked the system water pressure?

 

[Michael29068]

I have already contacted Vokera on this problem and they pointed to the thermistor which I then replaced and still the problem persists that is why I posted this thread. I have checked the water pressure and checked the press switch as well.

 

[diamondgas]

Can you get the boiler to standby? Turn all external controls calling for heat off and turn the fuse spur on, what happens? Explain the sequence of events that occur.....!

You say you've checked this and checked that, replaced this & replaced that .. tell me, are you a qualified engineer or an enthusiastic DIYer. Your honest will decide where we go from here.

 

[Michael29068]

Thanks Diamondgas, I am an RGI (Register of Gas Installers Ireland} I am not at the premises at present but will do as you suggest and let you know the sequence of events that occur, I will also contact Vokera i nthe morning as they were unavailable today.(Bank Holiday in Uk}. Thanks.

 

[diamondgas]

Thanks Michael29068. Reason I suggest is that some boilers go through a pre-check. It'll be interesting to know if you can get it to standby then when you call for heat what sequence of events occur. Tends to be call for heat, am I cold, if so - pump, fan, ignition, lift-off! And all the little things in between ... o/heat, fan off B4 on .. blah, blah! If I'm on something unfamiliar I like to at least establish that the boiler will sit in standby before I ask it to do some work!

Now that you've established that you're gas savee, ppl might be less weary of assisting

 

[d.roche]

hi michael..... im an RGI boiler man too in CORK!! this is a very strange one?? i have nothing to offer beyond what youve done and been told but im looking forward to hearing how you get on?? keep us posted and good luck

 

[Michael29068]

Hi again, I have not even managed to get this boiler into the standby mode for more than 1 second before the red led will start to flash. With the boiler in the off position when I turn the fused spur on the led will flash after 1 second approx .Vokera are also running out of suggestions again pointing to the thermistor and wiring to it which I have checked and am satisfied are giving the correct resistance to the pcb (13.5 kohms).Thanks.

 

[d.roche]

if you are not using an original vokera thermister i have had issues before with using other brand thermisters

 

[diamondgas]

Hi again, I have not even managed to get this boiler into the standby mode for more than 1 second before the red led will start to flash. With the boiler in the off position when I turn the fused spur on the led will flash after 1 second approx .Vokera are also running out of suggestions again pointing to the thermistor and wiring to it which I have checked and am satisfied are giving the correct resistance to the pcb (13.5 kohms).Thanks.

Have you tried temp wiring out the water pressure switch? Process of elimination time I'd guess. On standby the only thing i can envisage the boiler continually checking is the system pressure! Doesn't matter what the gauge says. It's possible that the pump when started will drop the pressure, that's if it gets to that stage or the PCB runs through an initial component check on establishing power? I'd remove the two spade connectors to the switch and connect them together, turn the boiler on and see? Some AP switches also pre check that the fan is off before bringing them on. 3 wires to APS. That could also be a possibility although it looks like this boiler only has 2 wires to APS .. It sound like hair pulling time!!!

 

[Michael29068]

I have fitted a genuine Vokera thermistor. Thanks.

 

[Michael29068]

Hi Diamondgas, I have already done what you have suggested with the water pressure switch but I have not done anything with the AP switch, this switch has 3 wires to it. I think I will have to bite the bullet and pass this boiler over to Vokera service to solve this problem. Thanks.

 

[diamondgas]

Hi Diamondgas, I have already done what you have suggested with the water pressure switch but I have not done anything with the AP switch, this switch has 3 wires to it. I think I will have to bite the bullet and pass this boiler over to Vokera service to solve this problem. Thanks.

Now that is a perfectly acceptable approach Michael. I've taken a hit once or twice through lack of knowledge, still not ashamed to say I still do! If you have the time though you can always arrange a joint visit as a learning curve? The customer appreciates honesty at the end of the day!

 

[Michael29068]

Thanks Diamondgas and all, I will try to arrange a joint visit as I am intrigued with this fault and would like to see it to its conclusion.
Once again many thanks for your input.

 

[aggis]

Hi,
just a thought is the polarity correct?
Ntc resistance, is it the same at the sensor as at connector at pcb? if different wiring.
Selector switch check for correct continuety in operation?
Overheat ok?

 

[d.roche]

good god this is unreal!!!! the only thing is i dont think this goes to lockout ie red light until the sequence reaches ignition stage??? so really this rules out water pressure and APS??? it has to be thermister or wiring or board...... screw vokera for the sake of all service engineers dont give... vokera guy will just call with box of parts he wont have a clue about real diagnosis work like us???

 

[diamondgas]

good god this is unreal!!!! the only thing is i dont think this goes to lockout ie red light until the sequence reaches ignition stage??? so really this rules out water pressure and APS??? it has to be thermister or wiring or board...... screw vokera for the sake of all service engineers dont give... vokera guy will just call with box of parts he wont have a clue about real diagnosis work like us???

You changed your nick mick?

 

[d.roche]

what does that mean diamond gas???

 

[diamondgas]

what does that mean diamond gas???

I mean are you, d.roche, the same as michael29068 the person who started the post??? Your post read to me as if you were familiar with the particular boiler in question! Come to think about it though you can't be! My mistake d.roche.

 

[Michael29068]

Hi again, thanks Aggis for your input, polarity is correct, ntc resistance correct at pcb, selector switch ok, and overheat stat ok.
In reply to D. Roche the boiler as I ha

 

[Michael29068]

To D.Roche, the boiler as I have already said goes to fault condition (red led flashing) within approx 1 second of switching on the fused spur,with the selector switch in the off position. At face value the the problem would appear to have to be in the items you mentioned but I have changed both thermistor and pcb and carried out all applicable checks on the wiring etc and still have not identified the problem, therefore that is why I am suggesting to the customer that he let Vokera solve this fault as I am not able to resolve it. Thanks.

 

[d.roche]

ok no problem michael..... sure keep us posted? im sure at this stage your head is wrecked.... p.s. i wasnt at all being smart in case you thought i was.... iknow exactly what you were going through

 

[CMalin]

Hi,
Soz but why was the APS ruled out, has it been checked?
does it spark before it locks out? If not i'd look for a loose airline or bad air seal???
if it does - Does the gas valve open?

Saying that I'm not familiar with the model or the instructions...