I am not an expert on Lennox equipment, but it looks like the 13ACX is a basic condenser with only a 5 year warranty. The XC14 appears to be better built, quieter and has a 10 year warranty. Unless there is a big price difference I would recommend the XC14.

An uncased coil is OK provided the installer builds an access panel in case the coil ever needs to be cleaned or serviced.

Are you saying you going to use the interior of walls as the supply and returns? This is a bad idea in my opinion.

I would also prefer the XC14 and with a cased coil.

IMO

Way oversized for anywhere in NJ. Where are you. You will be running very short cycles. Not good if dealing with humiity. Curious: what is the input on the furnace?

I'm in Camden County. I have a 4 ton, 2 stage unit (original was 4 ton single stage) for my 2500 SF home. It runs at about 3 tons 99+% of the time.

What is balloon frame?

V

This post was edited by veesubotee on Fri, Apr 12, 13 at 10:20

I agree with previous post about the size of the AC. Unless there is missing information, I would think 2-2 1/2 ton max.

IMO

mike_home, when you say:

"Are you saying you going to use the interior of walls as the supply and returns? This is a bad idea in my opinion."

are you familiar with balloon framed houses? Could you explain why it's a bad idea? They definitely used interior walls for the air supplies and now I'd just like to do the same with the returns if I can.

Veesubotee-

A balloon framed house has wall studs that run the entire height of a two story house....from the sill to the second floor top plate. Most houses built from the mid 1800's to 1940 in the US are balloon framed. Today, lumber that strong and long isn't as readily available. It's very easy to do rewiring with this type of house, however it's a dangerous house in a fire since there are no fire stops (although you can add them).

When I bought the house it had just had the furnace for the hot air put in the year before. I thought it was oversized, but I can't justify getting a new furnace. Also, one of the hvac technicians said that since it's multi-stage, it's blows at the lower stage for most of the time and they probably made it the larger size one so that I could blow cold air which is harder to move. (?)

By input, do you mean fuel type? It's gas.

Also, from what I'm reading, the condenser units are 2-3.5 tons....so why would that be too big?

This post was edited by magsnj on Fri, Apr 12, 13 at 13:09

Yes, I'm familiar with the Lennox G61MPV 'gas' furnace. No, input is the rating of the furnace in BTUs per hour (how much heat (gross) is being produced (at 100%). So your furnace is 90+% efficient--a 100K input unit would 'output' 90,000+ BTUs per hour.

If you post the furnaces complete model number, the blower size can be determined. Yes, cold air is heavier, but to oversize the furnace based on an oversized a/c, is doubly foolish (been there--had that).

Are you saying that your furnace can handle a/c units ranging from 2 to 3.5 tons? If you only need 2 or 2.5 tons, you wouldn't install a 3.5 ton unit. And judging by your square footage, you don't need a 100k unit.

V

Thanks V. I'll check the exact unit number when I get home.

I'm not saying that if I only need 2 or 2.5 tons I would install a 3.5 ton unit. I'm saying the furnace was already there when I bought the house so I have to work with what I have. I just want to know where to go from here with choosing an a/c unit and listing the options that were recommended to me by the HVAC technicians.

Were any of the options offered, a heat gain/loss calculation?

V

I imagine the spaces between the wall studs are not air tight. There will be a lot of loss on the supply side. On the return you are going to sucking in all the dust and debris found inside the walls.

Just because the previous owner used the wall cavities for duct work does not make it right. It is a cheap and easy way to circulate air.

Is it feasible to snake flexible ducts up through the wall cavities? You may have to place two ducts in parallel in order to get sufficient air flow.

I assume the furnace was oversized in order to compensate for all the losses. I am in central NJ. I would be curious to know how much it cost to heat your house during the past year.

V. No, one was not suggested. I've looked into getting an energy audit but in my area nj only has one certified (i think it's bpi?) company that DOES NOT seel anything besides an energy audit which I see as a conflict of interest. The one company that it looks like soley does energy audits has not been iin businesss long enough to satisfy me.

Mike_home, if you know any good a/c people in nj, please recommend them. My monthly gas bill is $165.

Why would the wall cavities cause more air loss than putting it in a closet? I'm not sure they did it b/c it was cheaper (not sure it is cheaper), I think they did it b/c htere isn't much closet space in older homes. I can tell you the bedrooms are nice and toasty warm in the winter (but that may be b/c hot air rises, not b/c there isn't air loss.

Where in NJ are you located?

If you used closets you would need to run a hard duct. It would be sealed and there would be no air loss.

My model is G61MPV-091

Monmouth county

with balloon framed walls there is no insulation
in the walls. this adds to the cost of heating
& cooling.
putting ductwork in joist bays usually results
in lots of duct leakage, if ducts are panned joists.

aside from bpi which does energy audits,
check with resnet.us for energy raters.
have ductwork tested for leakage before
adding more leaky ducts.
air sealing of the house will probably save
you quite a bit of cash and make it easier
to heat and cool.
always ask for someone with several years
of experience in existing balloon framed houses.
compared to most stick builds, balloon framing
is a whole different house dynamic.
we have quite a few balloon framed house
here in south La. they are always a challange
due to excessive air movement in the walls.

best of luck.

The contractor I would recommend is in Mercer county. You are out of his area. Also he is a Carrier dealer. It makes sense to get a Lennox condenser and try to get a match with the furnace.