Chances are, all 3 are guesstimates. Without a heat calc (manual J), quotes based on 'increments...' are just a guess.

The 5 ton blower does not give you the option of blowing more air to the second floor. The amount of airflow for heating and cooling is selected by the installer to deliver the proper temperature rise (heating), or delta-t (cooling). There are some (slight) possibilities to adjust airflow up or down.

So, if your current a/c is a 2.5 ton unit, you need to have 1000 CFMs of air, +/- an allowable amount.

What are the sizes of the equipment being replaced?

In all probability, your duct system is undersized/poorly designed. Going to a furnace that will deliver more air (higher CFMs due to size and VS blower, will result in more noise, less comfort, and possible premature failure.

V

Thank you for the response.

What is the difference between a 5 ton blower and a 4 ton blower then? I just assumed (mistakenly likely) that the 5 ton could blow more air.

The current a/c is a 3.5 ton unit, but we are NOT replacing it at this time.

The furnace that is being replaced is a Lennox, 110,000 BTU (but only 75% efficiency I believe).

Any opinions on the systems themselves?

Thanks again!

pete

you are making a big deal over nothing. The blower CFMs are adjustable.

I would want to see a heating load calculation in writing for your climate and your design temperatures inside and outside.

More is not better.

IMO

OK, so the blower difference apparently isn't a big deal.

Does anyone have an opinion on the quality of the actual units I'm comparing?

Trane XV95 vs. Rheem RGRM vs. Lennox G61V.

Also, it may be a longshot, but anyone have a recommendation for an installer in the Des Moines, Iowa area? I'm 99% confident that I have weeded out at least 5 lower quality companies but I believe my final two are fairly solid.

size, size, size...

and you will want a good two stg thermostat.

you want to verify that your selection meets the 95% eff threshold to qualify for tax credit.

IMO

I'm sorry tigerdunes, I didn't follow your first comment on "size, size, size." Throwing out the Trane from consideration, the Lennox and Rheem are identical in terms of BTUs, efficiency, etc. So is there a QUALITY difference between the two systems? For example, I was told that Rheem would likely be a little louder (no biggie, especially since its in the basement). But how about reliability between companies? Any difference? Or comfort of systems?

I have been looking at at thermostats, and am thinking of the Honeywell VisionPRO IAQ. Yes, all of the selections I am talking about meet the 95% threshold.

If the dealer suggested that the Rheem might be a bit louder, they probably don't plan on doing any adjustments to the cooling airflow via the dipswitches on the control board (many installers don't it seems). I've never liked the idea of too much airflow during a/c mode (over 450 cfm/ton). What size is your current a/c? The Trane with a "4 ton" blower can handle airflow settings up to a 5 ton unit, and likewise the Rheem "5 ton" blower can be adjusted to meet (but not exceed) the requirements of a 3.5 or 4 ton unit. Hope that clarifies the blower.

for ryan

can the XV95 80K blower be adjusted up to handle the 3 1/2 ton condenser?

pete

Since you have a 3 1/2 ton AC condenser, you will need a furnace that has 3 1/2-4 ton blower capability. Generally, I think there is less difference in these two stg VS furnaces than high eff premium outside condensers. I do like St Steel heat exchangers and you would want to understand the warranty differences between the mdls if any.

HW VP IAQ is an excellent choice as long as installer is familiar with this thermostat.

IMO

Tiger,

Here's Trane's Product Data on the XV95. As you can see, the 80k 3 ton blower can handle a 3.5 ton system, and as you can see, theoretically the 100k 4 ton blower could move sufficient airflow for a 5 ton system.

Here is a link that might be useful: http://trane.com/webcache/un/furnaces%20%28furn%29/product/22-1814-03_04012009.pdf

Thank you for the post ryan.

My a/c unit is 3.5 ton, and is properly sized. So "4 ton" versus "5 ton" really wouldn't come into play here since my a/c is only 3.5 ton? I actually asked the dealer about setting the dipswitches to account for the 3.5 ton a/c and he said they would do that. I think I understand the whole blower situation now.

So lets say that my house calcualted to need 80,000 to 85,000 BTU OUTPUT. The Trane will give me a max of 95,000 OUTPUT and the Lennox will give 85,500 OUTPUT. Is 10,000 a huge difference? The extra 10,000 would seem a little like a safety net, but also it seems like the 2 speed might just run in the first stage non-stop and never need the second stage.

ryan thanks for sharing that link.

pete

I would not exclude the XV95. I would ask for a heating load calculation to be performed. the XV95 in the 80K mdl may be just the ticket and it can handle your condenser.

BTW, what age, brand, mdl AC condenser do you have?

as I have tried to emphasize, more is not better.

IMO

tiger: my a/c is a 2005 Payne, with new Lennox coils in 2007. It is a 10 SEER. Not very efficient but too new for me to consider replacing.

I'm going to inquire into a heat load calculation on Monday. From what I've read on other forums, people are kind of split between Rheem and Lennox on which they prefer. Some cited expensive lennox parts that were harder to get. Others loved them. Once I'm sure of the proper size, I think I'm probably splitting hairs between the units.

Ok, I received the numbers after the manual J calculation. The manual J load calculation gave an estimate of 79522 BTU's. This was figured with a -15 degree temp. The thermostat included is a Honeywell 6000.

So with that in mind, I have the following three options still being recommended:

1. Trane XV95, 100,000 BTU. 95% efficiency. (4 ton blower) Cost: $2,125 after all rebates and tax credit.

2. Rheem RGRM. 90,000 BTU. 95% efficiency. (5 ton blower). Cost: $1,728 after all rebates and tax credit.

3. Lennox G61V. 90,000 BTU. 95% efficiency. (5 ton blower.) Cost: $2,125 after all rebates and tax credit.

The dealer said he doesn't think the Trane is oversized and that the next size down in Trane would be cutting too close to the manual J recommendation for him to be comfortable.

So, any opinions on this? I'm leaning towards the Lennox or Rheem as they seemed sized properly for my house better. But between the two, I'm stuck.

after all that, we dont even get to hear what you decided on???

I'd go for Rheem....its just as good (arguably and cheaper)