My house has a Goodman split-system heat pump with an AprilAire
humidifier. The system is about 8 years old. The inside unit is
in the basement. The outside unit is just outside the basement,
on the north side of the house, about 20' from the inside unit.

Typically, the inside unit starts up about 10-15 seconds after
the outside unit. There is a humming noise coming from the
inside unit during this delay, but it goes away once the unit
starts up. However, I've noticed that occasionally the inside
unit won't start running. It will just sit there, making the
faint humming noise. I don't know how long the system will run
like this, because when I notice it happening I shut off the
system, let it sit for a while and then turn it back on. I'd
guesstimate that it has "run" like this a couple of times for at
least 15+ minutes before I noticed.

I've only noticed this behavour in the last few months, and only
seen it happen 4 or 5 times. I have no idea how often it may
have happened when I haven't been home.

There are two copper pipes coming out of the inside unit (I assume
they go to the outside unit). One is about the width of a pencil
and is uninsulated. The other is about 1/2" in diameter and is
wrapped in some kind of foam-rubber jacket. The thin pipe is
run alongside the thick pipe, with either duct tape or a plastic
tie every couple of feet holding them together. When the system
is off, the copper lines are cool/cold. When both units are
running, the lines are warm. When just the outside is running,
the thinner line becomes VERY hot. It is so hot, it has melted
the outside insulation of one of a low-voltage line that it is in
contact with. I don't know the temperature of the thicker copper
pipe when this happens.

If there is a problem, and I call in an HVAC repair-guy, is this
enough info to diagnose the problem and fix it, in spite of it
being so intermittent?

Over the summer, I had the opposite situation. The inside unit
ran fine, but the outside unit didn't run. In that case, it was
obvious there was a problem because the outside unit would not
start at all. It was fixed in about 10 minutes when the HVAC guy
replaced a capacitor (about the size of an 8-10 oz drink can).
Does the inside unit have a similar capacitor that could be on
its way to failing and causing this intermittent behaviour I'm
seeing?

thanks

"Kevin J. Phillips" wrote in message
...
My house has a Goodman split-system heat pump with an AprilAire
humidifier. The system is about 8 years old. The inside unit is
in the basement. The outside unit is just outside the basement,
on the north side of the house, about 20' from the inside unit.

Typically, the inside unit starts up about 10-15 seconds after
the outside unit. There is a humming noise coming from the
inside unit during this delay, but it goes away once the unit
starts up. However, I've noticed that occasionally the inside
unit won't start running. It will just sit there, making the
faint humming noise. I don't know how long the system will run
like this, because when I notice it happening I shut off the
system, let it sit for a while and then turn it back on. I'd
guesstimate that it has "run" like this a couple of times for at
least 15+ minutes before I noticed.

I've only noticed this behavour in the last few months, and only
seen it happen 4 or 5 times. I have no idea how often it may
have happened when I haven't been home.

There are two copper pipes coming out of the inside unit (I assume
they go to the outside unit). One is about the width of a pencil
and is uninsulated. The other is about 1/2" in diameter and is
wrapped in some kind of foam-rubber jacket. The thin pipe is
run alongside the thick pipe, with either duct tape or a plastic
tie every couple of feet holding them together. When the system
is off, the copper lines are cool/cold. When both units are
running, the lines are warm. When just the outside is running,
the thinner line becomes VERY hot. It is so hot, it has melted
the outside insulation of one of a low-voltage line that it is in
contact with. I don't know the temperature of the thicker copper
pipe when this happens.

If there is a problem, and I call in an HVAC repair-guy, is this
enough info to diagnose the problem and fix it, in spite of it
being so intermittent?

Over the summer, I had the opposite situation. The inside unit
ran fine, but the outside unit didn't run. In that case, it was
obvious there was a problem because the outside unit would not
start at all. It was fixed in about 10 minutes when the HVAC guy
replaced a capacitor (about the size of an 8-10 oz drink can).
Does the inside unit have a similar capacitor that could be on
its way to failing and causing this intermittent behaviour I'm
seeing?

thanks


Goodman units use this cheap piece of crap they call a blower delay
relay...its nothing but a stack sequencer, and NORMALLY, there is a 5-10
second delay before the blower comes on...but chances are, you have a bad
one, since we keep about 8 on each van....
There is a cap on the fan motor in the air handler, and its as big a piece
of crap as the GEs they use outside.

Does the inside unit have a similar capacitor that could be on
its way to failing and causing this intermittent behaviour I'm
seeing?

thanks


yes, it will likely have a similar capacitor, or the blower motor itself may
be about dead

I would call the same HVAC guy back out if you were satisfied with his work
and price last summer.

also, the thinner line is supposed to be hot

but not sure about the dufus that ran a low voltage line up against a hot
liquid line when the unit was installed

margarita wrote:

also, the thinner line is supposed to be hot

Make that *warm*. The liquid line should never run over about 20ºF above
the outdoor ambient temp, or a max of 120ºF in areas that push the
century mark in mid-summer. This isn't even close to being hot enough to
melt the t-stat wire's sheathing. On a heat pump the suction line
(bigger line) can however get quite hot in heating mode, especially when
the indoor blower fails to run. Normal temps of the suction line
(bigger line) in heat pump mode run anywhere from about 120º-170ºF. This
is still not hot enough to melt the sheathing, but then the t-stat wire
shouldn't be in direct contact with the suction line, which is supposed
to be insulated. There is a possibility of the suction line melting the
wire insulation if the indoor airflow becomes reduced or non-existent
due to a system fault.



but not sure about the dufus that ran a low voltage line up against a hot
liquid line when the unit was installed

This is standard practice.

hvacrmedic

There is a possibility of the suction line melting the wire insulation if
the indoor airflow becomes reduced or non-existent due to a system fault.


exactly the reason that you should not do this



but not sure about the dufus that ran a low voltage line up against a hot
liquid line when the unit was installed

This is standard practice.


Oh I would agree with you there, a lot of bad procedures are "standard
practice" among neanderthal HVAC techs. If I was in charge of the
licensing, about 90% of current techs would not be able to qualify and buy
refrigerant, the first thing they would have to do is pass a college level
course on basic thermodynamics, so they would have a ****ING CLUE how the
damn A/C system works!

unbelievable the lack of basic knowledge of the average HVAC goon

margarita wrote:

There is a possibility of the suction line melting the wire insulation if
the indoor airflow becomes reduced or non-existent due to a system fault.



exactly the reason that you should not do this




but not sure about the dufus that ran a low voltage line up against a hot
liquid line when the unit was installed

This is standard practice.



Oh I would agree with you there, a lot of bad procedures are "standard
practice" among neanderthal HVAC techs. If I was in charge of the
licensing, about 90% of current techs would not be able to qualify and buy
refrigerant, the first thing they would have to do is pass a college level
course on basic thermodynamics, so they would have a ****ING CLUE how the
damn A/C system works!

unbelievable the lack of basic knowledge of the average HVAC goon

Your sentiment might be a bit more reasonable if perchance you
understood the difference between an insulated suction line and an
uninsulated liquid line. There is no problem strapping the t-stat wire
to the line set. If the suction line overheats in heat pump mode then
the insulation will protect the t-stat wire. The liquid line (the bare
pipe) will never get hot enough to harm the wire except maybe in the
event of a structural fire or the Sun going NOVA. Your personal
experience seems to have translated into an irrational attitude toward
techs in general.

I agree that a licensee should earn that privilege rather than having it
handed-over-no-questions-asked for a fee. Some states are catching on,
NATE or similar certification becoming a prerequisite to licensing.
We're getting there, but it won't happen overnight--putting half the
HVAC workforce out of work over a short timespan would cause one helluva
crisis, not just for the industry, but for the customer as well. Some of
the people in alt.hvac that you protest feel precisely the same about a
good number of techs, some of which have taken up residence there. Maybe
they enjoy getting berated regularly. Goes along with being stupid. But
there are still plenty of techs that simply don't correspond to your
statements. If you haven't met one, then you're probably just a ****ing
cheapskate that hires the cheapest outfit in town. If you want a bigger
fish, then you have to use bigger bait.

hvacrmedic

"margarita" wrote in message
...
also, the thinner line is supposed to be hot

but not sure about the dufus that ran a low voltage line up against a hot
liquid line when the unit was installed


On a heat pump, in heat mode, with temps lower than 40F, you cant bet its
NOT.

"margarita" wrote in message
. ..
There is a possibility of the suction line melting the wire insulation if
the indoor airflow becomes reduced or non-existent due to a system
fault.


exactly the reason that you should not do this



but not sure about the dufus that ran a low voltage line up against a
hot liquid line when the unit was installed

This is standard practice.


Oh I would agree with you there, a lot of bad procedures are "standard
practice" among neanderthal HVAC techs. If I was in charge of the
licensing, about 90% of current techs would not be able to qualify and buy
refrigerant, the first thing they would have to do is pass a college level
course on basic thermodynamics, so they would have a ****ING CLUE how the
damn A/C system works!

unbelievable the lack of basic knowledge of the average HVAC goon


Since you want to go there...
I bet that the insulation on teh low voltage wires melts at a higher temp
than the insulation on the "suction" line...you know...the HOT one when its
in heat mode on a heat pump...Gee....how come its not all melted and ****ed
up?
I mean...even tho you think that the liquid lines hot in heat mode...

Thanks everyone for your input. Now that I know the behavour I'm
seeing is not normal, I've made an an appointment for a repairman
to stop by this weekend.

Kevin