Firebird 90 Boiler Issue any advice?

alwaysonthego

Have a Firebird 90 Oil Burner and we went to put the heat ( hasnt been used in a good while, through the summer ) but we noticed/heard that the boiler cut out after a few minutes and no heat to the rads

We have done a bleed on it and no joy and its still cutting out approx 5 minutes from the time of being turned on?

Any advice would be greatly appreciated?
Thanks

jimf

sounds like a possible seized circulating pump

John.G

alwaysonthego wrote: »

Have a Firebird 90 Oil Burner and we went to put the heat ( hasnt been used in a good while, through the summer ) but we noticed/heard that the boiler cut out after a few minutes and no heat to the rads

We have done a bleed on it and no joy and its still cutting out approx 5 minutes from the time of being turned on?

Any advice would be greatly appreciated?
Thanks

Have a look through this thread, this particular problem turned out to be the capacitor as Jimf had suggested at the time.

https://www.boards.ie/vbulletin/showthread.php?p=107281652

agusta

If your getting water when you bleed the rads,everything points to the circulation pump.It probably is not gone.The armature in the pump is more than likely stuck from lack use over the summer.
https://www.youtube.com/watch?v=QyK48asOLUY

John.G

agusta wrote: »

If your getting water when you bleed the rads,everything points to the circulation pump.It probably is not gone.The armature in the pump is more than likely stuck from lack use over the summer.
https://www.youtube.com/watch?v=QyK48asOLUY

If the water is not circulating for whatever reason then would would think that the hi limit stat would have operated which requires manual resetting by first removing its cover and then pressing the reset. If its a burner/motor associated problem then its the burner reset button. The OP hasn't said which reset button he's pressing, assuming that the boiler is actually locking out, he does state that the boiler is cutting out after a few minutes.

Edit: Do modern gas and oil boilers now have a anti blocking function as solar controllers have for years, my solar controller switches on any relay output(s) for 5 sec at noon each day if they havn,t operated in the previous 24 hours.

Wearb

John.G wrote: »

If the water is not circulating for whatever reason then would would think that the hi limit stat would have operated which requires manual resetting by first removing its cover and then pressing the reset. If its a burner/motor associated problem then its the burner reset button. The OP hasn't said which reset button he's pressing, assuming that the boiler is actually locking out, he does state that the boiler is cutting out after a few minutes.

Its unlikely that he has to reset anything if its the circ pump. The boiler stat should be turning it off before the hi limit stat needs to kick in. Its not in every instance that the residual heat keeps building up enough to operate the hi limit stat.

Unlikely to be the capacitor when it starts and runs like described. It could of course be poorly maintained and setup which can cause such problems also, but -like jim first suggested- my money is on the pump not operating.

Wearb

John.G wrote: »

Edit: Do modern gas and oil boilers now have a anti blocking function as solar controllers have for years, my solar controller switches on any relay output(s) for 5 sec at noon each day if they havn,t operated in the previous 24 hours.

If you mean something to run the circ pump and motorized valves every now and then, then not on oil boilers. I dont know about gas.

John.G

Wearb wrote: »

If you mean something to run the circ pump and motorized valves every now and then, then not on oil boilers. I dont know about gas.

Yes that's what I mean. Just now I had a look at the eManual for a relations Vokera Vision 20S and it does have this function.

"• anti-block function – the anti-block function enables the pump
to be energised for short periods, when the appliance has
been inactive for more than 24-hours"

agusta

e.g, if the boiler stat is set at 60,yes it is unlikely to trip the hi limit with the residual heat rise.however if the boiler stat was set at 85 it probably would trip the hi-limit .the hi-limit will trip at 114 degrees.
Op did not say they reset anything.boiler runs for 5 min.there should be a little heat circulating in.So it points to a circulation issue

Wearb

John.G wrote: »

Yes that's what I mean. Just now I had a look at the eManual for a relations Vokera Vision 20S and it does have this function.

"• anti-block function – the anti-block function enables the pump
to be energised for short periods, when the appliance has
been inactive for more than 24-hours"

It must open a zone valve or some other sort of feature before operating the pump. Every 24 hours seems way overkill.

John.G

Wearb wrote: »

It must open a zone valve or some other sort of feature before operating the pump. Every 24 hours seems way overkill.

Yes it seems a bit that way alright. From your own experience when you get one of these pumps going again by turning the pump shaft with a screwdriver can you feel the extra resistance before it turns? and what causes it to "seize" and do the pumps run away again indefinitely after freeing up, I hadn't heard about it until I joined Boards.ie and I know lots of people with +10 year old pumps that never seem to have this problem even when stopped year after year for at least four months of the year.

Wearb

Sometimes there is a perceptible restance. Sometimes I don’t notice it. It seems to happen with dirty systems more. I suspect that it has to do with particals falling out of suspension after prolonged non use. There might be other reasons such as too great a head for the pump, but I’m unsure.

Wearb

Forgot one question. I think they do give periodic trouble afterwards. People learn how to get them going, so no callbacks until pump fails.

John.G

Wearb wrote: »

Forgot one question. I think they do give periodic trouble afterwards. People learn how to get them going, so no callbacks until pump fails.

Just carried out a test on my Firebird Heatpac 90s which with the nozzle fitted gives ~ 20 KW output.
I fired it up with the circ pump disabled and it ran for 7.5 mins before cut out, it was out on the hi limit stat and certainly didn,t seem to cut out on the normal stat setting of 75C (mine) as I could hear the water gurgling inside for at least 2 or 3 minutes before cut out. By calculation, the water contents of the boiler should be raised to 111C from 20C in this 7.5 mins assuming 20 litre boiler contents, this would correspond to the hi limit stat setting of 110C/115C?. If the normal stat had cut it out at 75C then again by using similar calcs I reckon that the boiler should have cut out after 3.5 mins so it continued to fire for another 3.5 mins after this.
Seems a bit strange as I fired it up again after cool down (pump re enabled) and it cut out normally with no funny sounds.
I suppose its hard to say what really goes on in a boiler with no circulation and reinforces the value of the Hi Limit Stat.

Wearb

John.G wrote: »

Just carried out a test on my Firebird Heatpac 90s which with the nozzle fitted gives ~ 20 KW output.
I fired it up with the circ pump disabled and it ran for 7.5 mins before cut out, it was out on the hi limit stat and certainly didn,t seem to cut out on the normal stat setting of 75C (mine) as I could hear the water gurgling inside for at least 2 or 3 minutes before cut out. By calculation, the water contents of the boiler should be raised to 111C from 20C in this 7.5 mins assuming 20 litre boiler contents, this would correspond to the hi limit stat setting of 110C/115C?. If the normal stat had cut it out at 75C then again by using similar calcs I reckon that the boiler should have cut out after 3.5 mins so it continued to fire for another 3.5 mins after this.
Seems a bit strange as I fired it up again after cool down (pump re enabled) and it cut out normally with no funny sounds.
I suppose its hard to say what really goes on in a boiler with no circulation and reinforces the value of the Hi Limit Stat.

With the two phials in the same pocket, you might have a sticking boiler stat or kinked capillary. Next time put a multimeter temperature probe in the pocket also and if boiler stat hasn’t cut out at about 100°, give it a good belt of a stout screwdriver handle to see if that helps.

John.G

Wearb wrote: »

With the two phials in the same pocket, you might have a sticking boiler stat or kinked capillary. Next time put a multimeter temperature probe in the pocket also and if boiler stat hasn’t cut out at about 100°, give it a good belt of a stout screwdriver handle to see if that helps.

It certainly seems to cut out at ~ 75C under normal conditions, the only time that I can recall that it came out on the Hi Limit stat (in 13 years) was after a complete system drain down/refill and there were certainly pockets of air about in the boiler/system which I quickly cleared.

Wearb

John.G wrote: »

It certainly seems to cut out at ~ 75C under normal conditions, the only time that I can recall that it came out on the Hi Limit stat (in 13 years) was after a complete system drain down/refill and there were certainly pockets of air about in the boiler/system which I quickly cleared.

With both phials in the same pocket, how else could your results be accounted for?

John.G

Wearb wrote: »

With both phials in the same pocket, how else could your results be accounted for?

In the case above (air) it probably did cut out on the normal stat and due to heat soak the Hi limit one then operated, in the failed circ pump test, it would certainly appear to have tripped on the hi limit stat, maybe the very fast temperature rise meant that one stat is more sluggish in reaction time for whatever reason say a dirtier phial?.
I take it that in your experience a failed/stuck circ pump should not and does not in practice result in the Hi Limit Stat operating.?
It would be interesting to carry out the test on another boiler and see the results.

Wearb

John.G wrote: »

In the case above (air) it probably did cut out on the normal stat and due to heat soak the Hi limit one then operated, in the failed circ pump test, it would certainly appear to have tripped on the hi limit stat, maybe the very fast temperature rise meant that one stat is more sluggish in reaction time for whatever reason say a dirtier phial?.
I take it that in your experience a failed/stuck circ pump should not and does not in practice result in the Hi Limit Stat operating.?
It would be interesting to carry out the test on another boiler and see the results.

The occurrence of the hi limit stat operating (as suggested -by agusta I think-) is often related to how high the boiler stat is set. I have always assumed that when it operated (in the event of a failed pump) that it was the residual heat -after the boiler stat had operated some minutes before- that caused the hi limit stat to operate.

I never considered that it was the boiler stat also failing to operate that caused it.



I am inclined to think that your instance is in some way an isolated one, but I will keep an open mind on it.

Thinking about it; I have come across some installations where the room or cylinder stat just control the pump and leave it to the boiler stat to eventually cut the burner off. This was long before the term "Boiler interlock" was common.

John.G

Wearb wrote: »

The occurrence of the hi limit stat operating (as suggested -by agusta I think-) is often related to how high the boiler stat is set. I have always assumed that when it operated (in the event of a failed pump) that it was the residual heat -after the boiler stat had operated some minutes before- that caused the hi limit stat to operate.

I never considered that it was the boiler stat also failing to operate that caused it.



I am inclined to think that your instance is in some way an isolated one, but I will keep an open mind on it.

Thinking about it; I have come across some installations where the room or cylinder stat just control the pump and leave it to the boiler stat to eventually cut the burner off. This was long before the term "Boiler interlock" was common.

I have seen a relation's boiler trip out occasionally on the Hi Limit but he had the temperature setting fully up, he just reduced it a notch and had no more problems.
The OP hasn't posted back yet vs his problem, but it seems that his boiler was just cutting out on the normal stat so again it would be interesting to see if his circ pump wasn't performing.

jimf

by having the run stat at its max in some cases these can be as high as 90dg plus or minis 5 % accuracy


this is then too close to the hi limit stat of 110 dg as the static water in the water jacket will continue to rise in temp


imho the stats on these boilers are not very accurate anyway

circulating pumps don't have to stick to cause the issue sometimes they just get lazy like agusta

agusta

jimf wrote: »

by having the run stat at its max in some cases these can be as high as 90dg plus or minis 5 % accuracy


this is then too close to the hi limit stat of 110 dg as the static water in the water jacket will continue to rise in temp


imho the stats on these boilers are not very accurate anyway

circulating pumps don't have to stick to cause the issue sometimes they just get lazy like agusta

Hi-limit is 114,minus 3 differential degrees jimf

jimf

agusta wrote: »

Hi-limit is 114 degrees jimf

sorry mister mystery hole driller I promise
to be more accurate in future :p:p:p

and will u ans ur phone

agusta

John.G wrote: »

I have seen a relation's boiler trip out occasionally on the Hi Limit but he had the temperature setting fully up, he just reduced it a notch and had no more problems.
The OP hasn't posted back yet vs his problem, but it seems that his boiler was just cutting out on the normal stat so again it would be interesting to see if his circ pump wasn't performing.

It was the OP first post in 6 years so maybe the OP wont post back

jimf

agusta wrote: »

Hi-limit is 114 degrees jimf

actually if we are so perfect it is 111 plus or minus 3 dg

so up yours

agusta

jimf wrote: »

actually if we are so perfect it is 111 plus or minus 3 dg

so up yours

Jimmy Google

jimf

agusta wrote: »

Jimmy Google

if you took notice of your boiler install manuals you don't need google :P:P

and you a heating engineer as reported in some papers a few months back :p:p