Home Air Conditioning / Furnace set up...

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I will start off by saying am a bit naive when it comes to HVAC, so forgive me. I purchased our first home, a 1959 ranch, back in August 2017. We purchased it from a family that we know, so I do have a good deal of info / history of the home and items that were replaced over the years. The home was built without A/C which was common back in the 50's, so A/C was retrofitted some years later.

I am just curious, is this a normal set up? It appears that the furnace is on the bottom, with the A/C unit on top...I believe. I am wanting to at least know the basics of how our HVAC is set up. It appears both the furnace and the "indoor" a/c unit are 16 years old, while the "outdoor" A/C unit is around 6-7 years old.

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I've never seen anything like that. Most homes built in the 60s had The A/C and gas furnace as one unit on the outside. I have no idea what the building code is in FL. But, I'll bet you won't be able to go back with that setup, if you have to replace the furnace.
 
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That is the way mine is set up. Fan on bottom. Heat exchanger in middle. AC/HP on top.


Is the outdoor unit just AC? Or is it a heat pump? I don't what is normal in FL. In VA most of us use HP's.
 
Originally Posted by dishdude
Is it me or does that flue pipe look a bit sloppy?


As I have been poking around, I am noticing it is sloppy! I think I will have someone inspect it before the cold comes back and heat needs to be used. It doesn't make a good seal currently, and the flue pipe (which gets VERY hot) is sitting right next to some foam and other things that I think could be flammable.
 
i have the exact same furnace but mine is mounted horizontally . our was put in about 2004 or so. it seems to be a pretty common heater. its been pretty reliable ,but its not consider efficient these days
 
Originally Posted by CDX825
Nothing out of the norm there.

AC evaporator coils always sit on the furnace or in the plenum above the furnace.


Both mine and my parents have the furnace unit on top and the AC on bottom. Both are downdraft style units though.
 
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Last winter I was checking out how the furnace in my old house was doing and I (like gregk24 ) noticed that the flue was hot enough to cook pork chops. Concerning to say the least so I called in an a/c & heating man to have a look see. He found that the furnace was over fueling and cut back the gas and opened up the air to get it to a normal ratio. That stopped the super heated vent pipe and increased the heaters performance. What he did tell me was that, although the furnace had little wear and tear, it was old enough to be obsolete by about 3 or 4 generations, being only about 80% efficient on a good day. Before he adjusted the fuel the attic was warmer than the house. Now the attic is cool and the house gets warmer than before. Gas bill went down too. Maybe Greg's furnace is doing what mine was.
 
That is totally normal for an "upflow" configuration; this is the most typical installation for most homes.

There are also horizontal left/right and also downflow choices. Some units are multi-poise, others are purpose built.

Not the cleanest installation I've ever seen, but not the worst, either.
 
Typical gas furnace set up.

The furnace contains the blower motor which pushes air through the system.

The interior portion of the AC contains the evaporator coil. This is where liquid refrigerant converts into a gas as it absorbs heat from the air being moved by the blower motor.
The exterior portion of the AC system contains the condenser. This is where gaseous refrigerant releases the heat it picked up from evaporator coil and is compressed, via the compressor, back into a liquid state to repeat the process.
 
OP,
Couple notes:
-keep gas burner sensors clean (ash + dust)
-keep motor cage dust free (dust bunnies)
-choose a non-restrictive air filter and replace it when dirty (1-6 months, depending on your area)
-every couple years, clean the outside AC fins/"radiator"
 
Normal setup except for the flue pipe normally not run all the way to the furnace but still it's ok. The flue pipe is called b vent normal clearance is 1" and should be stamped on pipe just under the manufacturer name. Model number on the furnace is under the top loovered cover on either side and might have a born on date listed and the serial. You can Google the manufacturers and how the read their serial numbers for their age. Furnace is 80% efficience.
 
Wow, I have the exact same Rheem Criterion II as you do, and yes I have the AC evaporator (indoor unit) right on top.

Mine was 94 when my house was build, we added an AC 8 years ago and they put an evaporator on top and the condenser outdoor, the thermostat will run the blower in the heater and the AC compressor together, and that's your AC right there. It works fine without having to throw away a functional furnace just because you want to add AC (it can be a different brand).

If you want a more sophisticated design like 2 stage or dual speed, then you may need to change that out to a compatible unit as well. In many case it is not cost effective.
 
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