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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 8702
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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I have a Vokera 30 BHE (4 1/2 years old) I keep getting

Customer Question

Customer: I have a Vokera 30 BHE (4 1/2 years old) I keep getting Error 10. It goes for a bit, then fails. I have replaced the board and flue. Anything else I can do please?
JA: Thanks. Can you give me any more details about your issue?
Customer: That's it really, Error code 10. 4 engineers have attended so far and none have fixed the problem, what ever is causing it. Gas tank full, electrode fine. Running (when it does at 97+% efficiency, CO2 within .3
JA: OK got it. Last thing — JustAnswer charges a fee (generally around $18) to post your type of question to HVAC Experts (you only pay if satisfied). There are a couple customers ahead of you. Are you willing to wait a bit?
Customer: Yes. Shops all closed atm so will have to wait until Monday anyway
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Submitted: 1 year ago.
Category: HVAC
Customer: replied 1 year ago.
Vokera Unica 32 BHE
Customer: replied 1 year ago.
The 4 engineers that have attended were all Vokera Engineers, all spoke to their technical help desk to find the answer. All (including their experts) have shrugged their collective shoulders and are baffled. Sadly, I fear your experts simply looking up the answer in the manual won't work!
Expert:  Phil replied 1 year ago.


I will approach this situation from an applied physics point of view... my first assumption is that the printed circuit board has a microscopic crack in one of the thousands of circuits inside the printed circuit board and micro processors, these are almost impossible to trouble shoot and the strategy I employ is not found in any service manuals.

Expert:  Phil replied 1 year ago.

We can do a heat stress test on it.

Use a hair drier to slowly warm the printed circuit card up to120F or a bit warmer, but not over 140F... if there is any change in the error codes or other furnace behavior... the card has a cracked micro circuit that opens and closes as the card expands and contracts... that proves a bad printed circuit card.

No change however does not prove the card is good however... but achange proves the card is definitely bad.

We can go from there.

Expert:  Phil replied 1 year ago.

I see you have already replaced the board, however the flaw could be at one of the molex connectors, the heat stress test will show many (but not all) of those defects up.

Customer: replied 1 year ago.
Sorry, it's a brand new board, checked before it went in. The board is good and about 4 1/2 hrs old. The boiler is still giving Error code 10. The gas valve has been changed as well as the electrode and lead. The condensate outlet is good. Vokera experts on their tech help desk cannot assist. The 4 engineers that have attended here since 23 Dec have done their best but it is still not working!
Expert:  Phil replied 1 year ago.

The heat stress test is for the molex connectors at the board.

tell me please if that looks like the manual for your boiler or not. (all of us refer to manuals, auto repair shops have a wall filled with manuals, no one can remember every detail of all the equipment that has been made, it changes every year or two).

Customer: replied 1 year ago.
I'm holding the same one. The poor old engineers that have attended are completely flummoxed, as well as the tech help desk experts back at HQ.
Customer: replied 1 year ago.
TBH I think I'll have to wait until 4th Jan to start with another Plumbing engineer
Expert:  Phil replied 1 year ago.

You currently have a retired mechanical engineer on the line, with 56 years experience and consulting nationally for fortune 500 companies nationally, I stand to make nothing by working with you, my statistics here for the last 6 years are 98.8 success rate... you are welcome to blow that off if you like.

Let me know however if you would like me to spend a little time with you on this, for close to 1/10 of what one of those service calls has cost you.

If you do the heat stress test I think you might find the condense sensor plug in to the printed circuit board does erratic when warmed up... if that turns out not to be the case, following that wire to the condense sensor itself, and cleaning or replacing it has a good chance of solving the problem.

We can go from there if you wish, or I can opt out.

Customer: replied 1 year ago.
It's a BHE (is an outside boiler). It's pitch black outside now so I'll have to try that tomorrow. TY.
Customer: replied 1 year ago.
I'm on page 29 of the manual. Where a outs is this module please?
Customer: replied 1 year ago.
Expert:  Phil replied 1 year ago.

I tried to send you a mark up of the wiring diagram on page 29, reference to the CS sensor but that screen shot service appears to be bogged down with holiday traffic, you can find it there however.

It is shown on the lower third, right hand side of the printed circuit card, the symbol shows it as a rectangle with a large curved hook shape on top.

After 4 years it is also likely that the condensate trap needs to be removed and cleaned instructions for that are on page. 22.

Customer: replied 1 year ago.
Tay. Early job for me tomorrow morning I think, once this blasted storm has blown through. Again, TY for now.
Expert:  Phil replied 1 year ago.

There is no problem with that, post when you can,

Customer: replied 1 year ago.
Morning Phil, I've done all the above and can report a dramatic improvement in the time it takes to trip to error code 10. Sadly, in addition to this I now get error code 34. The gas regulations in the UK prevent me from dealing with this new problem. It tripped 9 times to 10 last night. I'm calling it a day. Thank you.
Expert:  Phil replied 1 year ago.

Hello again, if the heat stress test is what you are talking about, and you got those changes when you heated the printed circuit card have proven the printed circuit board is bad, and it needs to be replaced.

If my test proved to be what led to that discovery, I will appreciate a positive rating, rating will not increase your charges but is how Just Answer keeps score here, it is important that I keep mine as high as possible. Thanks.