Goodman failing

[mattm]

Filter has long since been taken out of the equation.

There is a filter correct ?

[Dog]

check flue for blockage,make sure no snow blocking it

[tinknocker service tech]

model and serail numbers would be helpful
brand realy doent mater only the numbers do

how was the unit working before this problem came along and what shape was the filter in when you changed it

[skoonen]

Before you have any repair done it would be worth while to have the guy that comes out inspect the heat exchanger for cracks/missing rings. Goodmans of that era had the older clamshell design and should qualify for a tradeup program if cracked/missing a ring. Better off getting a discounted tradeup than fixing the old one which may have a crack in it.

Its also much more likely to have a crack/ring problem if the thing was oversized and has airflow issues.

[jeffw_00]

Thanks skoonen - I'll pass that on.

Don't know model and haven't been able to find it, sorry.
No snow - 50DegF today

the filter was a bit clogged but problem recurred with it removed.
thanks
/j

[dash]

"except he also has an unconnected AC coil on top of his furnace"

Assuming that means it's there but nt connected to an outdoor unit,that's an additional restriction to air flow,over yours.


How long has it been there, and how dirty might it be??

[jeffw_00]

How long has it been there, and how dirty might it be??

came with the furnace, and who knows - i'll mention it to him thanks
/j

[bzzline]

I would next swap out main limit sw and then check all connections to fan motor

[Nubicon]

Suprise suprise, another goodmen thread...one would think that the company should atleast change their name.

Call a sevice guy and have him come out to the house....air flow issue.

So is it an AIRFLOW problem or a Goodman problem? It sounds like the furnace controls are responding exactly as they should in the given situation.

[coolwhip]

So is it an AIRFLOW problem or a Goodman problem? It sounds like the furnace controls are responding exactly as they should in the given situation.

Its a gooman installed by a hack that didnt understand the dynamics of air flow Id wager...they usually are Nube.

[jeffw_00]

not a nube, an old and experienced..... plumber (not an hvac guy).

It ACTS like an airflow problem, but best as we can tell, nothing has changed with the airflow (notwithstanding a gradual clog in the A/C coil?) so we suspect a furnace problem.
More airflow (primarily in the return) fixes it, so does that mean the extra airflow is counteracting some clog, or the furnace has gradually (or suddenly) become more sensitive to limited airflow?

wish I knew. I like the idea of swapping the limit switch though
/j

[everythingair]

Swapping limits out is something that is only done by those who do not understand the values of proper troubleshooting. Randomly replacing parts is a hit or miss fix at best but most times misses the cause of the problem which then returns shortly after parts have been replaced.

This furnace needs to be properly diagnosed for temperatial differential, gas pressures and gas-air mixtures etc. Replacing parts on a furnace can make a small matter into a major problem quite effectively.

[bzzline]

Why can we not pull out the a/c coil that we are not useing anyway. Did you not have a light that said the HI limit was tripped. That is a chep part unless being a plumper fixing frozen pipes is cheapper.