Biasi boiler buzzing

[Smirnofman]

Hi all, I've got a loud buzzing noise coming from my Boiler, sounds like the diverted solenoid, the boilers always been temperamental but always seemed to keep going but now I've only got heating and won't switch onto hot water, boiler fires up when hot water put on but does not get hot then switches off, is the solenoid as easy as unplugging, removing retainer clip and dealing for a new one or could it be something else and I've got it all wrong, also boiler keeps starting and stopping instead of running constantly and no temperature is showing on the gauge, could this be the thermister? Any help would be apprieciated

 

[terryplumb]

What sequence of the three LED lights do you get when hot tap is running
A/ the moment the tap is turned on
B/ whilst tap is still running for 1 minute.

When you say the temperature gauge does not show a temperature ,do you mean its at zero ? Even when central heating is on and radiators are hot ?

When referring to coil ,I assume you mean the actuator.
Biasi service manual for this garda model is quite comprehensive and well illustrated and gives clear instructions of how to test ,remove ,replace actuator. And can be downloaded if you don't have the actual manual ,which is A 4 in size and not to be confused with the user manual which is half that size. From Info you have given so far ,I suspect you have a number of faults .if the boiler does actually fire up when a hot tap is run ,but shuts down after several seconds ,and then fires up again for a few secs,shuts down ,repeatedly, I would suspect the plate HEX is blocked.

 

[Smirnofman]

Hi mate thanks for your reply, the temperature guage is always at 0 degrees, the buzzing has completely stopped now and when I turn on the hot tap, all three lights light up first then the boiler fires up but water doesn't get hot, the 2 outside lights alternate as if it running fine but water does not get hot, with the central heating, it constantly starts and stops and middle and right light flash in time, just we're trying to move house and last thing I can afford is a new boiler, ive included a pic of what i called a diverted solenoid

 

[Smirnofman]

Also When central heating is running, flame stops and pump keeps running but right green light is solid and middle red light slowly flashes

 

[terryplumb]

Looks like you have a few issues .if I have understood correctly...
1/ the boiler fires up on central heating demand. and right led is solid ,middle one flashing and left one not lit. Which seems odd as that sequence is indicating a faulty domestic hot water temperature probe. Do your radiators actually get hot ,central heating working OK or not ???
2/ all three led' s should only occur ,momentarily , lit together when mains supply is turned on to the boiler. If all three are lit together ( no flashing but solid ) at any other time its Indicative of a faulty pcb.
3/ pic has the actuator showing on the upper left side.

 

[Smirnofman]

Yeah the radiators get really hot still, just the heating seems to keep going on and off, doesn't stay on and run continuously, at the moment the heating is on but not fired up and I've got middle red and right green both flashing in time with each other, if I put hot tap on, boiler fires up and left and right green lights flash alternately but water doesn't get hot, with the hot water could it be the actuator that's knackered (causing it to buzz) or more likely to be the valve bunged up and the actuator can't open the valve ( I've ordered an actuator, is it as easy as taking out the clip, removing old one and putting new one on and securing with new clip

 

[terryplumb]

Ah ,the middle and right lights flashing simultaneously indicated a faulty central heating temperature probe. By the way when central heating is running the burners will not burn non stop.its normal for it to stop for a few minutes,then fire up for a few mins ,continually. To replace the actuator is pretty much as you describe ,but firstly isolate mains electric supply to the boiler.

 

[Smirnofman]

It fires up, then stops, then fires up then stops, dies this a few times, might run for 5 seconds, then stops then it can sit and do nothing then run for 10 minutes, would that be the temperature probe causing that? How hard is it to change or is it a professional only job?

 

[Smirnofman]

This what I need?

 

[terryplumb]

The biasi part no is BI 1001 117
GC part no is 164 -026
NTC probe
Not a fan of buying such things from e bay. A bona fida manufacturers part from a reputable CH parts supplier is favourite. Easy to fit but you have to drain down the primary circuit of the boiler. A word of warning ,randomly buying and fitting parts ,without on site diagnosis from a pro can turn out an expensive way to fix .there is no substitute for actually being on site.

 

[Smirnofman]

Ok I understand what your saying, problem is no one wants to work on these boilers and if they do, they want an arm and a leg to do so, just want to get it working well enough to sell the house