britony combi 80se burner goes on and off

[anks]

hope someone can help this seem a weird one.

The burner on the boiler keeps going on and off whithin 10 second intervals. The thermitor has been checked and appears to works correctly and also the air presure switch. The boiler has been cleaned to make sure it wasnt blocked and make sure the water was clearing but the problem just wont go. Its has if the burner is stoping due to the boiler being at operating temp but it is only just getting hot on the out pipe just before is turns the burner off. There is no fault coming up on the front display and the boiler is just over a year or so old. Any ideas much appreciated.................

Cheers

 

[B.O.B DOLE]

have you checked the flame sensor probe

 

[anks]

is there a way to check it or is there a specific resistence that it is suppose to be. I was thinking that if that was the problem then it should go into lock out and the red light should come on and then I would have to manually reset the boiler.....

Cheers for the help

 

[Agile]

This boiler uses step modulation.

Perhaps one of the gas solenoids is faulty or the valve section is sticking.

First check that all three have the same resistance.

Checking for sticking is logical but I would not want to explain that to a non-corgi.

Tony

 

[anks]

im here with a counsil plumber who is corgi reg'ed and he and me cant understand what is going on here we have checked the solenoids by taking the plugs off and they all seem fine. I will check the resistance to check they are alright....

Just to be shure your cler whit what the problem is.

The boiler starts up and seems ok the 10 secs later the burner goes off as if the boiler has reached temp and as soon as the out pipe cools (about 15secs) the boiler will start the burner again. The boiler will repeat this constanly.

We have put the boiler in 1/3 gas mode with the jumper which seems to shut the far left solenoid and the boiler will run but the water temp is not hot but more like luke warm..........

Any ideas

 

[Agile]

Removing the connection from each solenoid and seeing if the gas burner pressure reduces is a good way to see if they are all functioning properly.

IF they are, then at first sight IF the boiler is malfunctioning then its presumably a PCB fault. It might just be the correct operation?

HOWEVER before coming to any conclusion its necessary to understand EXACTLY how the boiler is designed.

IF I remember correctly you need to know that:-

1. On CH the boiler operates on 1/3 and 2/3 ONLY.

2. On DHW the boiler operates on 2/3 and FULL ONLY

3. FULL = 1/3 plus 2/3 !

I think that I am right but after 2/3 bottles of Dumisani perhaps I am 3/4 muddled? Or is that only 1/4 ? Or even 2/4 which equals 1/2 ?

Council employees or contractors are not always the best gas engineers because their pay rates ( about £8-£10 per hour ) are just a little below the rate for the best ( £20-£40 ).

Tony Glazier

P.S. just watch how everyone totally ignores that eloquent technical explanation of how this design operates and fixates on the hourly rates of good/bad gas engineers.

 

[anks]

Ive already done the pull the plugs off the soliniods and the boile burner will operate difernetly as you said. It has 3 and will change the burner.

Any ideas

 

[B.O.B DOLE]

another fault which can cause this is trapped air in the heat exchanger or a pump problem

 

[anks]

ill have a look at that then. Cheers for the help

 

[peter i]

hi anks. did you solve your problem as mine does exactly the same and has done since the day it was put in ?

 

[boilerbeasty]

My britony combi SE80 (manufactured and installed 1st half of 2002 I think) did this until the PCB went after a couple of years. On and off all the time, particularly during DHW at a low-ish temperature setting. It lasted about 2 years until a relay on the PCB failed (no suprise there).

The replacement one looked slightly different to the original (though it has the correct part number for the boiler, and the pin outs are the same). This one does actually modulate as described by earlier posters. Another incidental feature was the temperature LEDs on the front now do a kind of 'chaser' pattern in pairs when drawing hot water. This didn't happen before either - quite an obvious sign of a revised design.

 

[Phil@]

I had the same problem with my Britony, I traced it to faulty micro switch for DHW flow it was being closed by valve but contacts must have been dirty and although would fire boiler would not keep continuous contact so switching it on and off, new switch fitted and no problem since

 

[ianmcd]

I had the same problem with my Britony, I traced it to faulty micro switch for DHW flow it was being closed by valve but contacts must have been dirty and although would fire boiler would not keep continuous contact so switching it on and off, new switch fitted and no problem since

Well as the post is 17 years old I am guessing it has been fixed

 

[Phil@]

Yes may be 17 yrs old but I read it recently because of same problem and wanted some ideas so my reply may help someone else hey

 

[mcmoby69]

im here with a counsil plumber who is corgi reg'ed and he and me cant understand what is going on here we have checked the solenoids by taking the plugs off and they all seem fine. I will check the resistance to check they are alright....

Just to be shure your cler whit what the problem is.

The boiler starts up and seems ok the 10 secs later the burner goes off as if the boiler has reached temp and as soon as the out pipe cools (about 15secs) the boiler will start the burner again. The boiler will repeat this constanly.

We have put the boiler in 1/3 gas mode with the jumper which seems to shut the far left solenoid and the boiler will run but the water temp is not hot but more like luke warm..........

Any ideas

Council plumber equals Council flat. 2002? New boiler.