Hi everyone. This is my first post here so hopefully someone can help.

My oil-fired boiler has developed a problem which is becoming more and more frequent. For information the boiler is fitted with an Ecoflam Monoflame Minor 1 burner.

When the burner starts it is supposd to run the motor and fan for a few seconds to pre-purge the systm before trying to ignite it. Sometimes this is not happening. What happens instead is that the burner just sits there making a buzzing noise. No motor run, no fan - nothing apart from the buzzing. After about ten seconds of this the burner goes into lockout because it has not seen any ignition.

I have found that if I hit the burner assembly fairly hard with my fist I can usually get it to start running.

Also, I've only just really started experimenting but it would appear that the problem is temperature-related. For example, the boiler has been playing up all weekend but tonight I started running it at setting 3 on the boiler thermostat with the front panel off and it hasn't missed a beat. I have (literally) just turned it up to 6 (maximum setting) and left the front panel off and so far all appears to be OK.

I have done a bit of research myself and the prime suspects seem to be either the motor or the motor capacitor. The fact that the motor won't start makes me think it is the capacitor, but the fact that I can fix it by hitting it makes me think it is the motor getting stuck!

Any thoughts from someone who really knows their stuff?

Thanks in advance.

Can't really understand why the capacitor would respond to the well
aimed boot. It would seem much more likely to me that a terminal
somewhere is not quite tight - the boot would resolve that as would the
operation of changing the capacitor as the offending terminal would
have been messed about with. Plus this is quite likely to be
temperature related. If you've got access I would go round all the
connections and check them for tightness.

The other thing I would try would be to get some lubrication into the
motor bearings; they could be sticky as you suggest and the kick frees
it. It is possible a new capacitor could overcome this by the very
fact that it is new and just that little bit more effective. If you're
up to changing the capacitor yourself look in Yellow Pages for a local
company who do motor rewinds, that's where I got one when I blew up one
when messing about with the start timer on another motor.

Rob

***bump***

Looks like this is almost certainly temperature related.

The burner fired up fine this morning (still turned all the way up, still with the front panel off).

I'll leave it a few more days like to see if it carries on working. Bear in mind that at the weekend I was having to manually restart it using the "thump" technique about once every hour.

Ah, cheers Rob. Didn't see your reply until after I posted again.

Yep - I can see what you are saying. Certainly checking the connections would be a good idea and I'll try to do that one evening this week.

Maplins sell motor run capacitors for about £3 each so I just need to get mine off and check what type it is. I believe that the Monoflame Minor 1 motor uses a 3uF.

"Digsy" wrote in message
news

Hi everyone. This is my first post here so hopefully someone can help.

My oil-fired boiler has developed a problem which is becoming more and
more frequent. For information the boiler is fitted with an Ecoflam
Monoflame Minor 1 burner.

When the burner starts it is supposd to run the motor and fan for a few
seconds to pre-purge the systm before trying to ignite it. Sometimes
this is not happening. What happens instead is that the burner just
sits there making a buzzing noise. No motor run, no fan - nothing apart
from the buzzing. After about ten seconds of this the burner goes into
lockout because it has not seen any ignition.

Either the motor/capacitor is failing/has failed or the oil pump is
stiffening up. There isn't enough Ommph to kick off the rotation. From
bitter experience you will find that the last of these you try will be the
right one!

the motor start and run capacitors are the cheapest option at around a
tenner. work up from there - motor around £80, pump also around £80 g


I have found that if I hit the burner assembly fairly hard with my fist
I can usually get it to start running.

the knock or jerk is often enough to get the first movement going to
overcome "sticktion". You could of course have a ball in the bearings which
has worn or chipped out out spherical and gets stuck sometimes. Remove the
motor and rotate it by hand gently to "feel" whats going on. At the same
time rotate the oil pump gently it should turn fairly smoothly although it
will be stiffer than the motor.


Also, I've only just really started experimenting but it would appear
that the problem is temperature-related. For example, the boiler has
been playing up all weekend but tonight I started running it at setting
3 on the boiler thermostat with the front panel off and it hasn't missed
a beat. I have (literally) just turned it up to 6 (maximum setting) and
left the front panel off and so far all appears to be OK.

I have done a bit of research myself and the prime suspects seem to be
either the motor or the motor capacitor. The fact that the motor won't
start makes me think it is the capacitor, but the fact that I can fix
it by hitting it makes me think it is the motor getting stuck!

Yep. or both - as the replacement motor comes with a capacitor and if you
are having to make a journey to get any parts you need it might be easiest
to get a motor straight away. Do try rotating as above first though.

Any thoughts from someone who really knows their stuff?

Its always easier to attack these situations with a vanload of spares :-)

Another bump.

I've been doing some reading up on single-phase AC motors and my symptons are classic for a starter ciruit failure. From what I've read this can be down to three things (assuming that the motor isn't plain and simple gummed up somehow).

1) Starter capacitor
2) Centrifugal switch
3) Starter windings

(1) Is a simple "replace it and see" job - relatively cheap. (2) Is a "motor apart and clean it" issue. (3) Would mean a new motor.

I don't think it's the starter windings because when it starts, it starts up fine. If the starter windings were fried I don't think it would start at all. The centrifugal switch gives a nice combination of an electrical fault that could be fixed by a swift kick so I think that's my prime suspect for now.

I'll have to take the motor out to look at the capacitor and check the connections so hopefully I'll be able to split the motor casing and get at / clean the switch at the same time.

In message .com, emma
writes
Don't know my stuff, but when our oil boiler was showing the exact same
symptoms, and our engineer suggested it was either the motor or the
motor capacitor, he suggested we change the motor capacitor first as it
was c.£20 for the capacitor rather than c.£150 for the motor. Turned
out it was the capacitor


Expensive for a motor start capacitor, that

--
geoff

"Digsy" wrote in message
news

Another bump.

I've been doing some reading up on single-phase AC motors and my
symptons are classic for a starter ciruit failure. From what I've read
this can be down to three things (assuming that the motor isn't plain
and simple gummed up somehow).

1) Starter capacitor
2) Centrifugal switch
3) Starter windings

(1) Is a simple "replace it and see" job - relatively cheap. (2) Is a
"motor apart and clean it" issue. (3) Would mean a new motor.

I don't think it's the starter windings because when it starts, it
starts up fine. If the starter windings were fried I don't think it
would start at all. The centrifugal switch gives a nice combination of
an electrical fault that could be fixed by a swift kick so I think
that's my prime suspect for now.

I'll have to take the motor out to look at the capacitor and check the
connections so hopefully I'll be able to split the motor casing and get
at / clean the switch at the same time.

The standard burner motor doesn't have a centrifugal switch. The capacitor
remains "in circuit" all the time the motor runs.

That's good news, then. So it's sort of like a combined start / run capacitor?

One less thing to check! Hopefully its just the cap.

Just to colse this off, I fitted a new capacitor a week ago and the motor has been firing up fine ever since.

Thanks for all the advice

Hey, I know this is an old post.
But it helped me s much with my boiler.
Exactly same symptoms. Buzzing no fan, nothing.
Changed capacitor. Boom!

Thanks all for this thread.

Saved my life.

Grant
On Sunday, 26 February 2006 20:42:39 UTC, Digsy wrote:
Hi everyone. This is my first post here so hopefully someone can help.

My oil-fired boiler has developed a problem which is becoming more and
more frequent. For information the boiler is fitted with an Ecoflam
Monoflame Minor 1 burner.

When the burner starts it is supposd to run the motor and fan for a few
seconds to pre-purge the systm before trying to ignite it. Sometimes
this is not happening. What happens instead is that the burner just
sits there making a buzzing noise. No motor run, no fan - nothing apart
from the buzzing. After about ten seconds of this the burner goes into
lockout because it has not seen any ignition.

I have found that if I hit the burner assembly fairly hard with my fist
I can usually get it to start running.

Also, I've only just really started experimenting but it would appear
that the problem is temperature-related. For example, the boiler has
been playing up all weekend but tonight I started running it at setting
3 on the boiler thermostat with the front panel off and it hasn't missed
a beat. I have (literally) just turned it up to 6 (maximum setting) and
left the front panel off and so far all appears to be OK.

I have done a bit of research myself and the prime suspects seem to be
either the motor or the motor capacitor. The fact that the motor won't
start makes me think it is the capacitor, but the fact that I can fix
it by hitting it makes me think it is the motor getting stuck!

Any thoughts from someone who really knows their stuff?

Thanks in advance.


--
Digsy

Ay' lad they don' t make thems condensers like wot they used to mate.
Brian

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please!
wrote in message
...
Hey, I know this is an old post.
But it helped me s much with my boiler.
Exactly same symptoms. Buzzing no fan, nothing.
Changed capacitor. Boom!

Thanks all for this thread.

Saved my life.

Grant
On Sunday, 26 February 2006 20:42:39 UTC, Digsy wrote:
Hi everyone. This is my first post here so hopefully someone can help.

My oil-fired boiler has developed a problem which is becoming more and
more frequent. For information the boiler is fitted with an Ecoflam
Monoflame Minor 1 burner.

When the burner starts it is supposd to run the motor and fan for a few
seconds to pre-purge the systm before trying to ignite it. Sometimes
this is not happening. What happens instead is that the burner just
sits there making a buzzing noise. No motor run, no fan - nothing apart
from the buzzing. After about ten seconds of this the burner goes into
lockout because it has not seen any ignition.

I have found that if I hit the burner assembly fairly hard with my fist
I can usually get it to start running.

Also, I've only just really started experimenting but it would appear
that the problem is temperature-related. For example, the boiler has
been playing up all weekend but tonight I started running it at setting
3 on the boiler thermostat with the front panel off and it hasn't missed
a beat. I have (literally) just turned it up to 6 (maximum setting) and
left the front panel off and so far all appears to be OK.

I have done a bit of research myself and the prime suspects seem to be
either the motor or the motor capacitor. The fact that the motor won't
start makes me think it is the capacitor, but the fact that I can fix
it by hitting it makes me think it is the motor getting stuck!

Any thoughts from someone who really knows their stuff?

Thanks in advance.


--
Digsy