Need Help, which system?

[steff3]

I am very much a nubee; I am on system overload so any advice is appreciated.
We need to change our 22 year old gas furnace and air conditioner. We have had three estimates ranging from 42.00 to 7,000.00. All happen to use Trane (one actually is American Standard but I understand it's the same)

Unsure of make of our existing units but if I remember right, I think Frazier-Johnson (or something like that) All three estimate the AC to be between 6.5 and 7.5 SEER and the furnace is 60K BTU. Unsure of tonnage but am guessing well under 2 ton. When the furnace was working at its best, it still was not forcing much air to the furthest three rooms.

#1 uses Am St and says I need to increase the BTU to 80K and that an 11 SEER unit is all we need (3 ton)

#2 says 80 BTU also, recommends 2 stage and a 11.5 SEER unit for AC (3 ton)

#3 says 60 BTU and the return air ducting needs to be sealed a bit. 13 SEER AC with the new gas but if I wished, 12 SEER with current gas but recommend the 13.
Difference of 900.00 between the 12 and 13 SEER AC's

All three seeemed knowledgeable and are reputable. The latter two seemed more professional however #1 is self employed and I am not worried because he does not drive a shinny new truck or pressed uniforms. He appears to have our needs at interest

Sorry for rambling on, as you can tell we are very confused. Any input is appreciated.

[Jultzya]

Originally posted by steff3
He appears to have our needs at interest


Have any of them done a load calc?

Is the old unit running 100% of the time and NOT heating your home?

If not, and there are just temperature variances, there is NO reason to upsize the furnace!!!!

Any one doing so IS NOT looking out for your best interest!

BTW, the new equipment is more efficient than the old, so right off the bat a new 60 is putting more heat in your home than the old one is.

[dan sw fl]

Originally posted by steff3


#3 says 60 BTU and the return air ducting needs to be sealed a bit. 13 SEER AC with the new gas but if I wished, 12 SEER with current gas but recommend the 13.

All three seeemed knowledgeable and are reputable.


Buy the one that is sized properly to handle humidity.
Location ___ ?

[beenthere]

Look up at the top of the screen, you'll see a red tab, use it and do your own load calc.

Then see if it close to what your contractors are saying. If not, show it too all 3, and the one/ones that balk about it, are the ones you don't want.

Might not be the furnace size, could just be the evap coil is dirty, and that is why you have poor air flow. A 60, and an 80,000 often have the same size blower.

[BaldLoonie]

Your profile doesn't say where you are, that would help us address which SEER is right.

The A-S/Trane models may say 11 in them but unless a very pricey coil is used plus a hard start kit on the A/C, you are getting 10 SEER. In many parts of the country, that's just fine.

[steff3]

Sorry, I have updated my profile. We are in Northern CA. Between Sacramento and the SF/Oakland Bay Area.

The Trane quotes are for XR11 12, and 13 series.

The old furnace would run quite a bit and not heat the house evenly. Would cycle off before it would reach temp setting of between 74 and 76 degrees. I would have to turn the thermostat(new) up 2 to 4 degrees higher than the desired temp just to get the room close to what we wanted, causing the furnace to run longer.

I know that #2 actually went outside and measured the front and side of the house to get sg ft (even though I had told him 1485). The other two took my word for it and all three would take a few minutes to do some figuring on paper. I don't know if that is how they do the calc or not.

#3 was the only one who pulled the front cover off the furnace to check the fan, return air, etc.

Sorry, but I am not very technical in this area at all.

Thanks for all your replies.

[travisfl]

Originally posted by steff3
... #2 actually went outside and measured the front and side of the house to get sg ft (even though I had told him 1485). The other two took my word for it and all three would take a few minutes to do some figuring on paper. I don't know if that is how they do the calc or not.It's not. To size your system properly they need to know the orientation of the home, the number and size of windows, the amount of insulation in walls and ceiling, and more.

Find a contractor who will do a true heat gain / heat loss calculation instead of guessing. Besides, AFAIK this is required by law in CA in order to get a permit.

http://www.proctoreng.com/articles/bigger.html

[steff3]

Wow! I had no idea it was that technical. Thank you for enlightening me.

[steff3]

I thought I saw something on the Trane "B" series as opposed the their"R" series and to stay away from th B stuff.

Anyone have advice? One of the contractors I am considering wants to sell the B series.

Thanks

[Jultzya]

Originally posted by jultzya
Is the old unit running 100% of the time and NOT heating your home?

[steff3]

The old unit runs most of the time, cuts out prior to set point, then cuts back in in a few munutes. This repeats on & on. I have to turn up the set point in order to keep the unit running enough to heat the house.

[Irascible]

B is for builder. It's not that much more for R, at least at the wholesale level. Get the R.

Here's the deal:

Our climate (northern Cal) is extraordinarily forgiving. Either the 60 or 80 would probably run just fine. The biggest difference between the two would be run time. Generally speaking longer run times are better. And generally speaking a "less than real hot" air will stratify less and mix better. But ultimately either will do the job. The elitists will blast me. That's fine. I'm one of them. But they don't know our climate like I do.

The same goes for cooling. We get away with grossly oversized air conditioners all the time because we don't have to worry about humidity. That is NOT the same thing as saying I endorse oversizing. I'm just giving you reality.

As far as SEER goes, it will take quite a number of years to get your money back. A 12 might give you a ROI in 5 to 10 years. A 14 may never give you ROI. Our summers are just too mild compared to a lot of the country. It depends on your usage and how long you plan on living there. It depends on brand too. A Goodman 14 SEER is a LOT less expensive than a Trane 14 SEER. Those that claim quicker ROI... well – let them prove it. And FYI: The whole “heating degree days” and “cooling hours” nonsense is a ruse. If you haven’t heard those terms yet, good.

Your biggest problem in terms of comfort as it relates to HVAC is the ducts - period, end of story. You need properly sized and balance supply ducts. And you might need to add one or more return paths to keep the bedrooms from pressurizing and knocking everything out of kilter. ANY new furnace at either BTU rating will give you the exact same problems you currently have unless you address the ducts. And did I mention? Ducts, ducts, ducts! Check my site for more.

[Jultzya]

Originally posted by steff3
The old unit runs most of the time, cuts out prior to set point, then cuts back in in a few munutes. This repeats on & on. I have to turn up the set point in order to keep the unit running enough to heat the house.

I would want to know WHY this is.

Is it because the ducts are not properly sized for the unit you now have? By which a larger unit will only make it worse and shorten the new equipments life.

Or is there some other issue (dirty coil, bad fan timer, limits, restrictive filter, gas pressure, etc)?

[dan sw fl]

Originally posted by Irascible
And FYI: The whole “heating degree days” and “cooling hours” nonsense is a ruse. If you haven’t heard those terms yet, good.

You mean Toronto and Dallas can not show their distinctions with these General WEATHER characteristics or more appropriately with the use of Temperature Bin Data?!

[Irascible]

I'm sure they can Dan. But an HVAC salesjerk isn't an amateur meteorologist who's fascinated by the climate differences between Toronto and Dallas. LOL!

Rather, he uses that data to ostensibly project energy savings and justify the purchase of higher SEER and higher AFUE equipment. The formula in question is used primarily by consolidators and consolidator wannabes. It doesn't take into account homeowner usage patterns whatsoever, which has more to do with energy consumption than even the weather.

So to be very specific, the data itself isn't the problem. It's how the hustlers use it.

[steff3]

Well, these last two posts are awesome! I can not tell you how much I appreciate them. Great info and advice. I agree with duct comments, I had one contractor spend a good portion of time on that subject.


Thanks for the info on the "B" & "R" series also, that goes with what I thought I had read. Will definitely go with "R"
Thanks again. This info is invaluable.

[steff3]

By the way, what is the opinion on R-22 VS R410A? Is one a better way to go than the other keeping in mind cost and availabilty?

[dash]

I'd go R410a,but You need to decide.

See http://www.410a.com for more info..

[beenthere]

We sell and service both r22, and r410a systems.

Right now r22 is less expensive.

Will it be 6 years from now, no one knows for sure.(doubtfull)

But r410a is here to stay.

[dan sw fl]

Originally posted by Irascible
It doesn't take into account homeowner usage patterns whatsoever, which has more to do with energy consumption than even the weather.

Your perspective is Great! !!