Furnace Running Better.

[hiskid1973]

Last year I had so much problem with my furnace hi limit running the furnace..This year before starting I wanted to pull the blower and vacuum it and the top of the plenum..During this I has a small mag lite to look in side..While I was sweeping I bumped the light anf it fell down in the front of the furnace..I said''Oh Lord that is probably the worse thing to happen..We'll I figured the only way to get the light was pull the burner and the front panel off..It turns out the light falls right out as I remove the panel carefully as to not damage the fiberglass gasket.
While there I fugure I might as well flip the shutters open that the AC blew closed..

Turns out for some reason with the close tolerances the shutters were bound and could not be opened so rather then pull the furnace I just removed the shutters..We''L I get her back and fire it up and the blower comes on and the air comes ripping out of the ducts..The burner keeps running for three minutes straight and the stat takes it off..Turns out those three baffles really were hindering the air flow.
I ended up thanking the Lord that what I though was bad with the flashlight falling helped me find a problem...Now I sorta see why the old furnace never had shutters in..

Any way now at the 30's and below it runs every 20 min..The burner runs for 3 min kicks off with stats set at 70 it get to 72 after the fan shuts down after 6 min...I feel much better the Hi limit isn't being used now..We just lost power 3 times from the icy trees/wires and it just came on again after 7.5 hrs..Thankful to have electric as some are still of...Looks like a wood stove purchase this year..

God Bless..Have a blessed Christmas..Kim

[Robert]

Hi Kim,

Is your a/c a self contained unit with the evaporator coil outside inside the condenser ?

If so, it would have two flex ducts, one return and one supply running from outside unit to underneath home.


One (return) would hook up to a return register in home and the supply to the main trunkline.


IF this is what you have, the close off damper is a must to protect the heat exchanger of furnace from condensation.



If not, maybe that furnace had that a/c set up where it came from if used.




Take care and Merry CHRISTmas,

Robert

[hiskid1973]

Hi Robert. Sorry I didn't get to your questions sooner.The AC is a package unit I got used and installed two summers ago.. The original miller furnace and AC have now been replaced with used units..There was never a damper on before with they old furnace and package AC..I only put one on since this site recommended it and I got it from here...I had overheat problems from day one..I think just the vanes created turbulence and slowed the flow even with all three fan settings..Now it really cranks air out and it shuts off with the stat now instead of the hi limit kicking off..It was going off hi limit even with the downgrade to a .5 gph nozzel...Thanks again and God Bless..Have a blessed Christmas and new year..Kim

[Robert]

With a self-contained or packaged a/c, without that close off damper, your furnace heat exchanger will get rusted from condensation as the cool air flows back into the furnace.


If there is an airflow problem, need to have the furnace and blower checked for compatibility with the homes ducting. Also be sure damper is installed correctly.

Did you have the cfm checked to see if blower was supplying correct airflow ?


Removing the damper will lead to future problems that could become dangerous if not caught in time.


Take care and best wishes,
Robert