Biasi Riva Compact HE

[tanker]

Guys,

Wonder if you could give me some advice regarding my Biasi Riva Compact boiler. It was working fine this morning and then suddenly it seems to have died on me.

When there is a call for either heat or hot water the boiler goes through its ignition sequence, ignites and stays lit for approximately 6 seconds before going out. The fan continues to run then it goes through the ignition process again after about 30 seconds, then it locks out. I've checked the fault finding section of the instructions but can't find a matching error (although there is a similar defect relating to the boiler lighting for a short while on C.H, with the hot water working as usual).

The three display LEDs show a fault relating to a 'lack of burner ignition (no ignition signal from the full sequence ignition device)'

Any advice on what may be the underlying issue would be greatly appreciated.

Yours,

Tank

 

[Agile]

The boiler is failing to recognise the flame.

For me to give you the correct advice which is appropriate for your model then I would need the model number and the serial number.

Edit, just noticed the "HE" in the title but not the posting.

In that case the condensate trap is probably blocked at the outlet or the sealing ball is stuck.

To test that disconnect the grey wire from the trap where it joins the flame detection wire. If it runs OK then thats the problem.

If it still occurs then R39 on the PCB is probably open circuit if its the single PCB used on later versions, again depending on which boiler model.

Tony

 

[tanker]

Tony,

Thank you for the advice, you were absolutely spot on. As soon as I read your post it set alarm bells ringing. The condensate pipe had frozen. A couple of kettles of hot water soon sorted out the problem.

Many thanks for your speedy response, it really is appreciated!

Merry Christmas

Toasty Tank!

 

[1981ash]

Many thanks Agile (saved me an unneccesary engineers visit!), i had exactly the same problem with mine (Biasi Riva Compact HE 24SM).

I checked the condensate pipe outside and sure enough it was frozen again a couple of kettles of water on the pipes and its all working fine again.

 

[Agile]

You have just done KevinTheGas out of another job with his slow hairdrier!

Tony

 

[noopin]

The Riva compact has a lock-out switch built into the trap but the Advance HE doesn't, I've just learned the hard way. I've just installed an Advance and left the condensate drain through the wall, awaiting connection to the stack. The drain pipe evidently curled slightly upwards and has frozen. I've now drained it, but will it relight?! It goes through the start-up procedure, fan starts, pump runs but just stops without the lock-out light coming on. If I run hot tap it does the same but the light does come on. Any thoughts?
Essentially, what I'm asking is - if the condensate drain fills, what causes the initial lock-out?
EDIT I've subsequently discovered that there's a detector in the bottom of the condensing heat exchanger, but the service manual doesn't identify it in schematics or wiring diagrams.

 

[blighty76]

I have the same problem. Just got back to a cold house after a night out and realised the boiler must have stopped working several hours ago.

On attempting to fire up the boiler, the left and right lights flash together for a few seconds. I hear what sounds like ignition and then about 4 seconds after that it dies out. It cycles like this a couple of times and then locks out. There is a little heat created in the pipes during this process.

Mine is also an Advance HE.

1 hour on hold to BG service and the soonest engineer is Monday - GRRRR.

Or should I say BRRRR.

 

[Agile]

Noopin, you have only just joined this site and I dont know if you are qualified to fit boilers!

On the M110 if the condensate pipe is blocked then the condensate backs up into the combustion chamber and eventually in theory shorts out the detection electrode. In practice the disturbance to the combustion might prevent the flame staying on but the effect is the same.

If you continuing trying to fire it up every five minutes until it locks out then it will probably relight eventually.

Blighty76, you dont say anything about the condensate pipe but if this is cleared yours might also eventually relight after a number of attempts.

There are two mechanisms, water on the ignition electrodes preventing ignition and water on the detection electrode preventing flame detection.

Tony

 

[blighty76]

OK thanks for your input Tony. I will tackle this again in the morning and see if I get anywhere.

 

[noopin]

Fair enough, Agile, I'm a Surveyor and experienced developer. Normal practice is for me to install the system and my GasSafe guy to make final connections, tests and commission. He's in Gran Canaria until Wednesday and if the boiler hadn't been on the 2nd floor, I'd have made the final drain connection straight away; so it's my own fault. I discovered there's a detector in the heat exchanger casing, but what bothers me is that the left LED always returns to 1 second "ON" blinking, without the thing having ignited, even briefly; as if it were OK.

 

[Agile]

Normal practice is for me to install the system and my GasSafe guy to make final connections, tests and commission. He's in Gran Canaria until Wednesday and if the boiler hadn't been on the 2nd floor, I'd have made the final drain connection straight away; so it's my own fault.

I discovered there's a detector in the heat exchanger casing, but what bothers me is that the left LED always returns to 1 second "ON" blinking, without the thing having ignited, even briefly; as if it were OK.

Well thats clear then that you have made an illegal installation !

The boiler will only start the ignition sequence when there is a demand for heat as shown by the two green are flashing together for CH or alternately for DHW.

A failure to ignite will include red lights.

Two sensors in the main HE are the flow sensor and the overheat stat. If the latter has tripped the whole heat exchanger has to be replaced.

I dont feel much sympathy for illegal installers!

You sound more like a building worker than a professional surveyor in a suit and tie!

Tony

 

[noopin]

"I dont feel much sympathy for illegal installers!" That's pretty obvious, but understandable.
"You sound more like a building worker than a professional surveyor in a suit and tie!" There's no need to be bloody patronising - I deliberately capitalised Surveyor. Phew - moving onwards in a spirit of honest enquiry:

This is what happens - left LED 1 sec blinking
Press reset - left and right flash together until reset released, when centre shows red briefly, returns to left LED 1 sec flashing
If reset held for more than 5 secs, both flash together, sounds like gas valve opens, fan etc, for about 10 secs, then back to left LED 1 sec flashing (no red at all)

 

[Agile]

Either you dont really have any demand for heating or hot water or there is some other installation error!

OR, and this is very rare, the PCB is faulty.

But this is an illegal install! Anything could be the cause!

When it has been properly installed/commissioned by a registered engineeer, if he thinks there is anything wrong with the boiler then he can call the manufacturers and request a warrantee visit.

Be aware that if its been installed incorrectly then they dont have to repair it and may well charge for having to make a second visit when the installation fault has been put right.

If the cause of the malfunction is an installer/user error then it will immediately become a chargeable call !

Tony

 

[noopin]

I don't deny liability for the breakdown, it worked fine for several days until the condensate backed up; it just won't reset fully to allow it to fire...if it wasn't the coldest night for years, I'd be less anxious.

 

[blighty76]

Ah well still no joy. I've been outside and wrapped a boiled towel around the condenser outlet to see if that will make any difference.