alix wrote:
Hi everyone - my apologies in advance for the long-ass post:
The time has come to replace the 25 year old furnace in my recently
purchased house. I'm planning on also replacing the central air while
I'm at it. While I'm not thrilled about having to put out the dough, I
am looking forward to resolving my biggest peeve with my current
system - which is that the air conditioning has trouble getting to the
upstairs of the house in the summer.
This is a ducting issue. Neither brand of unit nor size of unit is going
to correct this. If the t-stat is downstairs, then upsizing the unit
will only provide the imbalance in temps quicker. There are several
options for correcting this, the best being the addition of returns to
the bedrooms. Or it may be as simple as undercutting the doors.
Here is some related literatu
http://www.eere.energy.gov/buildings...esign-0782.pdf
My house is tiny - about 1,200 square feet. It's a Cape Cod -
officially it's 1.5 stories, meaning that the upstairs bedrooms are
actually in the attic, so to speak.
I have 2 quotes that I'm dealing with. The first vendor wants to
install a Trane furnace (2 stage, 92% efficient - 80,000 BTUs) and a
Trane AC unit (I think it's 14 SEER). He noted that I have asbestos in
my basement, which butts up against the "main" ductwork (sorry, don't
know the correct terminology); he said that the existing ductwork was
fine and that I wouldn't need to have the asbestos removed. He said
that my cooling problem might be the result of having the wrong sized
AC unit installed;
See above. You don't want this guy.
he also suggested that I raise the registers in the
upstairs bedrooms to the middle of the wall (about 3 feet up - they
are currently down around the baseboards) to help spread the air
around.
Deflectors are a much less expensive option. You can by them at most
home improvement centers. This will not however solve the temperature
problem, it will only provide better mixing; a more even temp throughout
the rooms.
Vendor #2 wants to install a Bryant 80% efficient 2-stage furnace
(70,000 BTUs) and a Bryant Puron Plus AC unit (13.5 seer - upgradable
to 14.5 for some extra $$$). He said that my cooling problem is
probably due mostly to improper air flow, and that I'd need to have
the asbestos removed so that he could make the return air trunk line
larger.
See above. You don't want this guy either. More airflow may be in order,
but a modification to the central return isn't going to solve the supply
balance issue. You'll get more airflow into both zones, but in the same
proportion as before.
The Bryant guy's quote is almost exactly $1,000 less than the Trane
guy's quote, but having the asbestos removed will even that out.
Anyhow, my questions are many - I know that they're difficult to
answer without actually seeing the situation, but here they a
- Could there be any equipment differences between the Trane and
Bryant brands that would explain the vendors' difference of opinion on
the size of the return air trunk line.
Again, return air size isn't the problem. It may be a problem as far as
capacity and efficiency is concerned, but it isn't the cause of the temp
imbalance. The Trane guy may have been correct about the size, but I
can't see it from here. I can tell you that the Bryant guy's plan isn't
going to work as intended.
- Any opinions on Trane vs. Bryant?
- The Bryant guy wants to charge an extra $250 to install a Honeywell
T8600 programmable thermostat.
That's your call. If you want to DIY on part of the install, then they
may or may not be willing to work with you on that. Your time is free,
ours is not. My company wouldn't bargain with you on this however. On a
new unit we install the stat, period! The reason for this is that we
don't want you ****ing up any of our equipment and then crying about it
and threatening lawsuits when it was entirely your fault that the board
is now fried. Don't be surprised if you and whoever you chose end up not
getting along so well.
I can buy that same model on the web
for $106.
So? See above.
Is there any great skill/advantage to having the contractor
install it? For $250, I could buy the thermostat and have my handyman
buddy install it - *and* wallpaper my bathroom after he's done.
I did the same when it came to treating my new fence. Bought a Wagner
sprayer and the wood treatment for a fraction of what they wanted to
treat the fence for me. The time required turned out to be considerable
however. (They were quoting mostly labor.) Normally I wouldn't have done
something like that, but it wasn't my idea to install the thing, but I
digress.
As it so happened a few of the slats warped (before treating), and they
refused to replace them for me. I didn't push the issue. I still had
enough savings left to replace a bunch of those *******s myself. But
there is no comparison between a fence and a piece of gas/electrical
equipment located within a house.
In the case of the t-stat, there is much more at stake, namely
liability. Your house could actually burn due to a miswired stat. It is
also likely that their price includes pulling a new t-stat wire. The
warranty issue is however enough on its own to refuse the bid under your
conditions. Even minus the new wire, they could lower the price, but
they would have to add it back to the unit. The profit has to come from
somewhere, where it is distributed on paper is sometimes just a formality.
Any other opinions, advice, etc. will be greatly appreciated. I really
would prefer to install the Trane - the warranty is better, and it's
just better looking, darnit - but the whole airflow argument concerns
me, and I don't want to put out a bunch of money for a new furnace/AC
if its performance is going to be hampered by inadequate ductwork.
Thanks much! - Ali
I'd shop around until you get somebody else who knows at least the
minimum basics about air distribution.
hvacrmedic