spark ignited furnace question
 

I've noticed recently on my spark-ignitied (not standing pilot) Olson Mini
Max furnace that the spark ignition runs a LOT longer before it stops and
fires than it did before.

in the last 1.5 years here, the furnace has just "bzzzz.poof", sparking for
maybe 4 or 5 seconds at most and lighting without fail. Now
(internittently) the unit will spark for 15 or 20 seconds and seems to
"timeout" and then light. other times it lights perfectly.

in my gas fireplace adventures, I know that there is a part in the furnace
that detects the presence of flame to tell the unit that the pilot is lit
(so stop sparking, and open the gas valve). what is the proper name for
this part? it seems that these devices are right at the front and fairly
user serviceable....

I am a handy person and really really hate to give money to a technician to
do super simple repairs....

any ideas?

b

Hamilton Audio wrote:
I've noticed recently on my spark-ignitied (not standing pilot) Olson Mini
Max furnace that the spark ignition runs a LOT longer before it stops and
fires than it did before.

in the last 1.5 years here, the furnace has just "bzzzz.poof", sparking for
maybe 4 or 5 seconds at most and lighting without fail. Now
(internittently) the unit will spark for 15 or 20 seconds and seems to
"timeout" and then light. other times it lights perfectly.

in my gas fireplace adventures, I know that there is a part in the furnace
that detects the presence of flame to tell the unit that the pilot is lit
(so stop sparking, and open the gas valve). what is the proper name for
this part? it seems that these devices are right at the front and fairly
user serviceable....

I am a handy person and really really hate to give money to a technician to
do super simple repairs....

any ideas?

b


These systems use a probe to electronically detect the pilot flame.
It's called "flame rectification". (Do a GOOGLE.)

Some systems use the same electrode for both the spark and
the flame detection; others use a separate probe.
If the probe is dirty or the plating gone, proper detection
will be sporadic. You can try cleaning it or replacing.
That part should be available.

Jim

I see the sparker with a large orange cable running to it. being the cold
season, the furnace is running reasonably often....so she's too hot to touch
right now and take a peek ;)

I will, however, disassemble tomorrow when its cool and take a closer look.
i've got a handy furnace power interupter switch right on the wall.....so I
can simply crank the tstat and stop the furnace from firing with the switch.
take apart, clean, and test fire without having to go all the way back
upstairs (heheh). sounds like a plan to me!

if cleaning the flame detection probe cleaning doesn't yeild improvement -
where do you think I can prodcure an additional one? also, what about an
installation/assembly manual for this furnace so I can see how it comes
apart??

thanks for the help!

b

"Speedy Jim" wrote in message
...
Hamilton Audio wrote:
I've noticed recently on my spark-ignitied (not standing pilot) Olson
Mini Max furnace that the spark ignition runs a LOT longer before it
stops and fires than it did before.

in the last 1.5 years here, the furnace has just "bzzzz.poof", sparking
for maybe 4 or 5 seconds at most and lighting without fail. Now
(internittently) the unit will spark for 15 or 20 seconds and seems to
"timeout" and then light. other times it lights perfectly.

in my gas fireplace adventures, I know that there is a part in the
furnace that detects the presence of flame to tell the unit that the
pilot is lit (so stop sparking, and open the gas valve). what is the
proper name for this part? it seems that these devices are right at the
front and fairly user serviceable....

I am a handy person and really really hate to give money to a technician
to do super simple repairs....

any ideas?

b
These systems use a probe to electronically detect the pilot flame.
It's called "flame rectification". (Do a GOOGLE.)

Some systems use the same electrode for both the spark and
the flame detection; others use a separate probe.
If the probe is dirty or the plating gone, proper detection
will be sporadic. You can try cleaning it or replacing.
That part should be available.

Jim

Hamilton Audio wrote:

I see the sparker with a large orange cable running to it. being the cold
season, the furnace is running reasonably often....so she's too hot to touch
right now and take a peek ;)

I will, however, disassemble tomorrow when its cool and take a closer look.
i've got a handy furnace power interupter switch right on the wall.....so I
can simply crank the tstat and stop the furnace from firing with the switch.
take apart, clean, and test fire without having to go all the way back
upstairs (heheh). sounds like a plan to me!

if cleaning the flame detection probe cleaning doesn't yeild improvement -
where do you think I can prodcure an additional one? also, what about an
installation/assembly manual for this furnace so I can see how it comes
apart??

thanks for the help!

b

You'd have to find the mfr of the ignition control; probably
made by a major controls co., not MiniMax.


"Speedy Jim" wrote in message
...

Hamilton Audio wrote:

I've noticed recently on my spark-ignitied (not standing pilot) Olson
Mini Max furnace that the spark ignition runs a LOT longer before it
stops and fires than it did before.

in the last 1.5 years here, the furnace has just "bzzzz.poof", sparking
for maybe 4 or 5 seconds at most and lighting without fail. Now
(internittently) the unit will spark for 15 or 20 seconds and seems to
"timeout" and then light. other times it lights perfectly.

in my gas fireplace adventures, I know that there is a part in the
furnace that detects the presence of flame to tell the unit that the
pilot is lit (so stop sparking, and open the gas valve). what is the
proper name for this part? it seems that these devices are right at the
front and fairly user serviceable....

I am a handy person and really really hate to give money to a technician
to do super simple repairs....

any ideas?

b

These systems use a probe to electronically detect the pilot flame.
It's called "flame rectification". (Do a GOOGLE.)

Some systems use the same electrode for both the spark and
the flame detection; others use a separate probe.
If the probe is dirty or the plating gone, proper detection
will be sporadic. You can try cleaning it or replacing.
That part should be available.

Jim

Hamilton Audio wrote:
I've noticed recently on my spark-ignitied (not standing pilot) Olson
Mini
Max furnace that the spark ignition runs a LOT longer before it stops
and
fires than it did before.

in the last 1.5 years here, the furnace has just "bzzzz.poof",
sparking for
maybe 4 or 5 seconds at most and lighting without fail. Now
(internittently) the unit will spark for 15 or 20 seconds and seems
to
"timeout" and then light. other times it lights perfectly.

in my gas fireplace adventures, I know that there is a part in the
furnace
that detects the presence of flame to tell the unit that the pilot is
lit
(so stop sparking, and open the gas valve). what is the proper name
for
this part? it seems that these devices are right at the front and
fairly
user serviceable....

I am a handy person and really really hate to give money to a
technician to
do super simple repairs....

any ideas?

b


Are you saying that the spark DOES light the pilot but the spark keeps
going, or are you saying that the spark FAILS to light the pilot and
the spark keeps going?

Mark

"Mark" wrote in message
oups.com...
Are you saying that the spark DOES light the pilot but the spark keeps
going, or are you saying that the spark FAILS to light the pilot and
the spark keeps going?

Mark

the spark ALWAYS lights the pilot and sets the furnace going (has never
/not/ lit)....its that sometimes
the pilot lights and the spark keeps going (situation 1 above).

b