My brother's heat was out. I went over to check it out. He said there
was a reshaped coat hangar tied between the gas line and the power feed
pipe infront of the furnace door. When he removed it, there was a
spark. When he heard the spark, the furnace immediately changed
operation. Later we found the 3A fuse on the electronic board inside
the furnace was popped. The best we can conclude is the spark blew the
furnace. But what is odd is that I can't see static electricity blowing
a 3A@24V fuse. The fuse does have 32V limit but still. Also I checked
and the gas pipe and wiring pipe are both grounded and at the same
potential. We ended up putting a 10A fuse in there since who can find a
stupid 3A fuse!?! I think they do that 8hit just to get you to pay $5
for a stupid fuse. a 3A trace can't be that much cheaper than a 5 or
10A trace...


2nd problem was that while we were working, his daughter started taking
a shower. That turned on the hot water heater. Then we saw the power
exhause fan start turning slowly in opposite direction of the arrow on
the wheel. Is that wheel supposed to go in direction of the arrow? We
never checked its operational direction so I thought I would ask here.
Either the heat was going up the chemney creating a draft and sucking
air through the furnace as well, or the exhaust was coming down the
chimney and back into the furnace. Not sure which.



--
Thank you,



"Then said I, Wisdom [is] better than strength: nevertheless the poor
man's wisdom [is] despised, and his words are not heard." Ecclesiastes 9:16

In article , (dnoyeB) writes:

| We ended up putting a 10A fuse in there since who can find a
| stupid 3A fuse!?! I think they do that 8hit just to get you to pay $5
| for a stupid fuse. a 3A trace can't be that much cheaper than a 5 or
| 10A trace...

Actually, they probably do this so that the fuse blows before an inherently
limited class 2 transformer destroys itself when/if the thermostat wiring
shorts. Or possibly the class 2 rating depends on the fuse because the
transformer is not inherently limited. Either way, it might really be worth
your time to find a 3A fuse...

Dan Lanciani
ddl@danlan.*com

dnoyeB wrote:
But what is odd is that I can't see static electricity blowing
a 3A@24V fuse. The fuse does have 32V limit but still. Also I checked
and the gas pipe and wiring pipe are both grounded and at the same
potential. We ended up putting a 10A fuse in there since who can find a
stupid 3A fuse!?!

Find a stupid 3A fuse. Get a 120V or 240V unit. If no one else has one,
go to a television repair shop and they'll probably be able to help you
for a buck or two.

--
All relevant people are pertinent.
All rude people are impertinent.
Therefore, no rude people are relevant.
-- Solomon W. Golomb

Al Moran wrote:
On 20 Feb 2006 21:47:57 GMT, ddl@danlan.*com (Dan Lanciani) wrote:

Either way, it might really be worth

your time to find a 3A fuse...

Dan Lanciani
ddl@danlan.*com



Yep, because now, whatever was causing the 3A to blow is just getting
warmer and warmer. Hope the op has his fire insurance paid up since he
fixed the symptom, not the problem.

Only if its a resistive short. Which is incredibly rare. Either way,
the 10A fuse was not intended to 'fix' the situation, its just there
because the local store did not have a 3A fuse and it was 8 degrees
outside...

I been doing automotive fuseing for about 10 years now so Im familiar
enough with them to know the risks.

My main question is about the exhaust fan spinning backwards.

--
Thank you,



"Then said I, Wisdom [is] better than strength: nevertheless the poor
man's wisdom [is] despised, and his words are not heard." Ecclesiastes 9:16

clifto wrote:
dnoyeB wrote:

But what is odd is that I can't see static electricity blowing
a 3A@24V fuse. The fuse does have 32V limit but still. Also I checked
and the gas pipe and wiring pipe are both grounded and at the same
potential. We ended up putting a 10A fuse in there since who can find a
stupid 3A fuse!?!


Find a stupid 3A fuse. Get a 120V or 240V unit. If no one else has one,
go to a television repair shop and they'll probably be able to help you
for a buck or two.


This is an ATO fuse, the type in cars. rated only for 32V no where near
120V. Well eventually get one from Radio Shack or ill get one from
work... 3A fuse is just silly. Anyway Im concerned about the reverse
exhaust fan direction. any opinion on that?

--
Thank you,



"Then said I, Wisdom [is] better than strength: nevertheless the poor
man's wisdom [is] despised, and his words are not heard." Ecclesiastes 9:16