When we budgeted for our house we established the HVAC budget based on an average of the high and low prices that the builder's HVAC sub gave. We set this as an allowance because I wanted to involved in the selection process of the equipment and features of the system. We were sill making change to floor plans, ceiling heights, and insulation so it was not unusual to have this setup as an allowance. We did not have exact specifications but we did estalish a set of desire features.

We start construction and my builder kept the move going very quickly but had really poor co mmunication with us as the homeowner. I could go on and on about it but let's just say after the framing stage he disappeared on us and only came back around punch list time.

During the process I tried to setup a time to meet with the HVAC sub but I never got a response from the builder. At the end while going through the punch list we asked what was the HVAC system that was installed? He finally got me in touch with his sub.

Here is what happened
We paid for a change order early on to go full open cell foam on the house. When that happened the HVAC had to have mechanical air ventilation and a 98% efficiency furnace. This also reduced the number of AC units to one. We also added 2 gas tankless water heaters. The furnace, ventilation, and the water heaters were all extra costs that were not envisioned originally by the builder because we were not doing full foam at that time.

My HVAC sub in an effort to stay in budget put in a simple 13 SEER unit instead of the 16 SEER, variable speed, and zoned unit.

At the end of the day I was $800 under the HVAC allowance but I didn't get the 16 seer system that I originally wanted. I would have paid extra for it. If I change it now I would have to pay for the new system and the wrong one.

I'm a little concerned because I wanted to focus on efficiency since I plan to live here for a long time. Should I pony up the money to change it or am I making a bigger issue out of it than it really is. We are in the Dallas,tx area.

If my builder had just communicated with me, this would not have happened. Or if he had just been involved in the decisions his sub was making,. He did stay in budget but it doesn't feel like he did me any favors.

What do you think?

You can get more information on the HVAC forum here.

Now - not having a zoned system when you wanted one may be worth the money to you to change out but it would be cheaper just to add the zoning.

Variable speed is very nice and maybe able to be handled without changing out the system.

Everyone loves to talk about efficiency but in the end you want to spend the least and use the least amount of energy. Far and away your most important issue is solar gain. Control your solar gain better and you will more than make up the difference between seer 13 and 16. Plant a few trees....

Do you have anything in writing stating what is included with your system? Signed change orders in writing amending the original contract docs?

that is a big difference. in Texas, like in La. humidity
is a factor. the vs would have helped to control humidity.
getting the minimum efficiency hvac..as much as we depend
on hvac would be unacceptable to me.

of course I sent back the 14 seer unit the supply house
sent me for the 15 seer unit I had ordered.
as your hvac will last for 12-15 years, you have to
factor in comfort and what it will cost you for the
13 seer as opposed to the 16 seer.

you say you added gas tankless water heaters..where
are they installed? exterior of house?

hvac contractor could resell 13 seer. happens
all the time. now you have top of the line furnace
and lowest hvac. doesn't make sense for a cooling
climate.

just as you invested in insulation (agree with
you about the walls lz) the hvac choice should
have been consitered just as importantly.

as far as your load calc..divide tons installed
by sq ft of house. got 500 sq ft per ton?
that is what it sounds like to me. hope I'm wrong though.

best of luck.

it would be fair to say that the ball
was dropped by builder, hvac company
and homeowner.

you are right it was my fault to let it get that far along. But I made it know from the beginning that I wanted input on the design and I asked about it several times during the process but didn't get a response.

The house is a 3130 sf home with 10' ceilings throughout. I don't think he used a 1 ton/500 SF ratio.

I guess the question I have now is is it financially sensible to pay for the new system (A/C?

We don't have that many windows, though the ones we do have are large. They are Low-E, Argon gas filled, tinted.

We tried to make the right choices.

talk to the builder & hvac company. together, nicely.
explain to them what you have to us.
even the hvac guy would have to agree that top
of the line heating deserves better than minimum
efficiency single stage a/c.

at 626 sq ft per ton (not 500 sq ft per ton rule of thumb)
the variable speed a/c will run in low speed and
remove humidity. the single stage unit runs full
blast all the time, shortcycles & doesn't remove
humidity.

it is your comfort at stake.
in our cooling climate we run a/c 8 of 12
months.

did anyone speak to you during the process
about adding fresh air? whole house dehumidifier?

don't beat yourself up, but do make an effort
to get the better a/c for your new home.
like I said in my first post..hvac company
can easily sell 13 seer to someone else.

best of luck.

I'd talk to the builder. I had a 4 ton changed to a 3 ton at no cost to me because they screwed up. Seems like you can get a discount or free changeout. Mine was changed out 30 days after move-in. I am sure the unit can still be resold at no discount to an unsuspecting customer ... the practice is probably commonplace. If they were honest, they could just offer an extra year warranty and anyone would take it.

5 tons for a well designed and shaded 3100 sqft house is too much - even in Texas.

Five ton sounds big, you have closed cell foam, but again you have 10 ft ceilings.

Ask hvac dealer what it would take to replace A/C unit. It is new unit he may give you credit. $2k +$500 install - credit for old unit (le's say $500) = may not be so bad to get what you want....

zoning will be extra

single speed furnace, 98% efficiency

Open cell foam

10 ft ceilings with, 12 ft in living

HVAC sub said $3500 to replace 13 SEER with 16 SEER, outside coil only

I actaully hav ezero confidence that anyone involved in the house constructing knew what they were doing. My builder tried to convince me that the 98% efficient furnace meant I was going to have great cooling bills. The HVAC sub told me he never installs 13 Seer units in his new homes. I asked why did he do it in this case? No answer...

I live in North Texas, 2-3 months heat, 2 months nothing, 7-8 months cooling.

have you paid in full hvac & builder?

I'm pretty easygoing, but this isn't something
I'd accept. it will cost you more every month
until replaced. not to mention losing the 2 stage
cooling & zoned system.

what would the legal stand point be?
any contract stating efficiency of hvac system?

best of luck.