Air conditioning decision

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My house is about 90 years old, a ~1500 sq foot three bedroom colonial. I'm in Northern NJ, and it's getting pretty hot outside. I currently have not enough window units to keep the whole house cool, and I'm thinking it's time to do something.
I've had three AC people in to make their sales pitch. what they have offered (and all of the pretty similar in price is:
a)Split system to just do the first floor (18000 BTU). Outside unit in back yard under the window that now has the big AC, inside unit on living room wall. A couple of fans as needed. ~$3500 (minus $500 state rebate)
b) Same as A, but with a second inside unit in the ONE bedroom (30,000 BTU). ~$5500 (no rebate)
d) Same as C but with a third inside unit to hit a second bedroom (40,000 BTU). $8000
d) Central system (3.5 ton). Outside unit in same place, inside unit in attic, ductwork in 3 upstairs closets, vent in EVERY room first & second floor, return in upstairs hall. ~$7500. 1 year parts & labor, 10 years parts warranty.
I'm at a loss as to which is the right thing to do. Assuming I can afford any of these (I can), what would be the relative advantages/disadvantages of each? How about the relative cost of operation?
Thanks - I want to get this done ASAP, because my other option is to move to Antarctica.
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On Wednesday, June 18, 2014 12:00:45 PM UTC-4, rangerssuck wrote:

You don't describe your current heating system and that knowledge may affect people's recommendations.
I'm guessing that your first 3 options are variations on mini-splits that do not require duct work. I'd go with the last option. While doing the duct work is initially an additional cost it will never have to be done again.
Also that is a fairly large system for that many square feet. It makes me want to guess there are possibly a lot of single pane windows and/or poor insulation. Anything you can do to beef up the house insulation or windows will be well invested too.
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On Wednesday, June 18, 2014 12:20:36 PM UTC-4, jamesgang wrote:

I'm in Northern NJ, and it's getting pretty hot outside. I currently have not enough window units to keep the whole house cool, and I'm thinking it's time to do something.

ffered (and all of the pretty similar in price is:

back yard under the window that now has the big AC, inside unit on living r oom wall. A couple of fans as needed. ~$3500 (minus $500 state rebate)

BTU). ~$5500 (no rebate)

00 BTU). $8000

attic, ductwork in 3 upstairs closets, vent in EVERY room first & second f loor, return in upstairs hall. ~$7500. 1 year parts & labor, 10 years parts warranty.

rd any of these (I can), what would be the relative advantages/disadvantage s of each? How about the relative cost of operation?

ve to Antarctica.

ect people's recommendations.

do not require duct work. I'd go with the last option. While doing the d uct work is initially an additional cost it will never have to be done agai n.

e want to guess there are possibly a lot of single pane windows and/or poor insulation. Anything you can do to beef up the house insulation or window s will be well invested too.
There are single pane windows with storms. The insulation in most rooms is virtually non-existent and beefing that up would be a huge job. Previous ow ners had done some sort of foam injected through drill holes (outside). In the few outside walls I have opened for various repairs, you can see that t he foam has deteriorated to the point that it's pretty much gone. replacing it with another foam or blown cellulose would be tough, as there's enough of the old stuff there that it would impede the flow of new stuff. There is loose-fill in the attic floor, and I've thought about beefing that up eith er by laying fiberglass on top or pulling it all out and doing foam. But af ter all that, the house will still be plenty hot in the summer.
As far as heat goes, it's gas-fired steam. I hate it, but it's what I have.
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On 6/18/2014 1:00 PM, rangerssuck wrote:

It makes me want to guess there are possibly a lot of single pane windows and/or poor insulation. Anything you can do to beef up the house insulation or windows will be well invested too.

most rooms is virtually non-existent and beefing that up would be a huge job. Previous owners had done some sort of foam injected through drill holes (outside). In the few outside walls I have opened for various repairs, you can see that the foam has deteriorated to the point that it's pretty much gone. replacing it with another foam or blown cellulose would be tough, as there's enough of the old stuff there that it would impede the flow of new stuff. There is loose-fill in the attic floor, and I've thought about beefing that up either by laying fiber- glass on top or pulling it all out and doing foam. But after all that, the house will still be plenty hot in the summer.

it's what I have.

From what I know, gas fired steam is low percent efficiency. Wastes a heck of a lot of heat up the chimney. I'd be tempted to take a closer look at the attic AC unit, and maybe get a high efficiency furnace up there also. At night you might be able to turn down the steam, and use 90% natural gas heat.
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On Wednesday, June 18, 2014 5:29:59 PM UTC-4, Stormin Mormon wrote:

If he puts in a furnace too, IDK why he would turn down the steam. Just turn it off. I agree if he goes with the whole house AC approach, he should look at a combo furnace/AC, even more so if the existing heat eqpt is old. The equipment cost difference to add heat isn't much, but running the gas to the attic would add a considerable amount too.
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On 6/18/2014 6:07 PM, trader_4 wrote:

It may be possible to run through the floor and ceiling of a closet, and just leave the black iron in there. Yes, some real advantages to put in heat also. I did an AC hook up a couple years ago, the gas furnace was cheaper than an air handler, so that's what they used.
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On Wednesday, June 18, 2014 12:20:36 PM UTC-4, jamesgang wrote:

+1
If I had to guess, it's probably hot water. I'd also be interested in why they want to put the AC in the attic. That would be my last choice. If a basement is avaialable and it can go there, that would be my first choice. Attic makes doing the upstairs easy, but then the downstairs is harder. With a basement, it's the opposite. I'm not a big fan of putting the AC in the attic if it can be avoided. The attic is 115, the basement is 60. I'd much rather be routing air around the basement, than in the attic. They typically use flex duct in the attic, which has couple inches of insulation. Also, if the AC leaks condensate water, in the basement it's usual a minor issue. Not saying I would never put it in the attic, if it reduces costs substantially, is the only way, etc, then I would probably do it.
I'd get at least one more quote on doing the whole house.

I tend to agree. We also don't know the priorities/values here, the solutions range from doing just the first floor to the whole house. Without knowing how important doing all versus just the first floor is, not much I can add.

+1
Or it could be the installers don't know what they are doing, too. On first glance, it would seem that oversizing is OK. It's better to be somewhat oversized than under for sure, but if it's oversized too much then you run into problems. Main one is that it will have so much capacity it will cool off the house quickly, before the AC has time to take out the humidity. That's also an advantage of two stage AC, it can run at the lower output when not that much cooling is required, better controlling humidity. Certainly not essential, but I think it can add to comfort.
Just some things to think about.
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On Wednesday, June 18, 2014 1:03:36 PM UTC-4, trader_4 wrote:

l. I'm in Northern NJ, and it's getting pretty hot outside. I currently hav e not enough window units to keep the whole house cool, and I'm thinking it 's time to do something.

offered (and all of the pretty similar in price is:

n back yard under the window that now has the big AC, inside unit on living room wall. A couple of fans as needed. ~$3500 (minus $500 state rebate)

0 BTU). ~$5500 (no rebate)

,000 BTU). $8000

in attic, ductwork in 3 upstairs closets, vent in EVERY room first & second floor, return in upstairs hall. ~$7500. 1 year parts & labor, 10 years par ts warranty.

ford any of these (I can), what would be the relative advantages/disadvanta ges of each? How about the relative cost of operation?

move to Antarctica.

ffect people's recommendations.

y

ce.

at do not require duct work. I'd go with the last option. While doing the duct work is initially an additional cost it will never have to be done ag ain.

me want to guess there are possibly a lot of single pane windows and/or po or insulation. Anything you can do to beef up the house insulation or wind ows will be well invested too.

Correct about the mini split not require any ducting. The only inside work would be getting the pipes through one closet to an adjoining closet. This would be done at ceiling level, so would be, for all intents, invisible.
The basement isn't a good option for two reasons:
1) I use that space for my workshop, and it already has a low ceiling. Duct work would make it unusable for anything else - I'm short but not THAT shor t.
2) using the attic allows the first-floor ducts to run inside existing clos ets. using 8" round or 11x3 oval, even with the insulation wouldn't sacrifi ce too much space. To go the other way (from basement to second floor) woul d require a LOT more construction (in already finished space).
I will certainly ask about a two-stage unit, if it doesn't add too much cos t.
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On Wednesday, June 18, 2014 1:34:25 PM UTC-4, rangerssuck wrote:

ial. I'm in Northern NJ, and it's getting pretty hot outside. I currently h ave not enough window units to keep the whole house cool, and I'm thinking it's time to do something.

ve offered (and all of the pretty similar in price is:

in back yard under the window that now has the big AC, inside unit on livi ng room wall. A couple of fans as needed. ~$3500 (minus $500 state rebate)

000 BTU). ~$5500 (no rebate)

40,000 BTU). $8000

t in attic, ductwork in 3 upstairs closets, vent in EVERY room first & seco nd floor, return in upstairs hall. ~$7500. 1 year parts & labor, 10 years p arts warranty.

afford any of these (I can), what would be the relative advantages/disadvan tages of each? How about the relative cost of operation?

o move to Antarctica.

affect people's recommendations.

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that do not require duct work. I'd go with the last option. While doing t he duct work is initially an additional cost it will never have to be done again.

es me want to guess there are possibly a lot of single pane windows and/or poor insulation. Anything you can do to beef up the house insulation or wi ndows will be well invested too.

k would be getting the pipes through one closet to an adjoining closet. Thi s would be done at ceiling level, so would be, for all intents, invisible.

ctwork would make it unusable for anything else - I'm short but not THAT sh ort.

osets. using 8" round or 11x3 oval, even with the insulation wouldn't sacri fice too much space. To go the other way (from basement to second floor) wo uld require a LOT more construction (in already finished space).

ost.
Given your insulation situation then it might not be all that big. But don 't let people tell you that bigger is better. An ac doesn't just cool the air, it also removes humidity. A unit that is too big will not run long en ough to get the humidity down leaving the interior air feeling clammy. A t wo stage unit does a lot to alleviate this problem since it can run for lon ger periods at low speed.
I'd go ahead with laying unfaced fiberglass in the attic. That's cheap and easy. I agree about the walls, hard to do anything there. The storm wind ows help some but not as much as double pane windows would. But that's a p ricey deal and you'd have to figure out if its worth it.
Nothing wrong with an attic install, millions of houses have them. Make su re they are using r8 flex duct. You might let them put in the duct and the n cover it when you add the unfaced fiberglass.
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On 06/18/2014 11:00 AM, rangerssuck wrote:

My house is 115 years old and about 1900 sq ft.
I am going to replace my furnace and get central air . Though I am now getting by ok cooling a few rooms with window units, the only thing than makes sense if I'm going to re-do this is to get central air.
I am having my 100amp service upgraded to 200 amps in about three weeks.
Since the summer here has been very cool I may not bother to get furnace and central air until next year
The 3.5 ton unit sounds about right and may really be needed for any days where the temps go up around 100 F
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On Wednesday, June 18, 2014 12:57:34 PM UTC-4, philo  wrote:

I'm in Northern NJ, and it's getting pretty hot outside. I currently have not enough window units to keep the whole house cool, and I'm thinking it's time to do something.

ffered (and all of the pretty similar in price is:

back yard under the window that now has the big AC, inside unit on living r oom wall. A couple of fans as needed. ~$3500 (minus $500 state rebate)

BTU). ~$5500 (no rebate)

00 BTU). $8000

attic, ductwork in 3 upstairs closets, vent in EVERY room first & second f loor, return in upstairs hall. ~$7500. 1 year parts & labor, 10 years parts warranty.

rd any of these (I can), what would be the relative advantages/disadvantage s of each? How about the relative cost of operation?

ve to Antarctica.



I did the electrical upgrade (to 200A) last spring. We had MANY days (weeks on end) around 100°F kast summer, and it's 90°F right now.
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On 06/18/2014 12:03 PM, rangerssuck wrote:

One other thing:
be sure your house is insulated.
I insulated the attic soon after I bought the house...but only had the windows replaced within the last couple of years. The good seal and thermal glass helps.
To me, anything over 90 and humid is hard to take if it lasts more than a day or two.
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On 6/18/2014 9:00 AM, rangerssuck wrote:

I think you'll regret NOT doing the whole house.
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On Wednesday, June 18, 2014 4:15:38 PM UTC-4, mike wrote:

I'm in Northern NJ, and it's getting pretty hot outside. I currently have not enough window units to keep the whole house cool, and I'm thinking it's time to do something.

ffered (and all of the pretty similar in price is:

back yard under the window that now has the big AC, inside unit on living r oom wall. A couple of fans as needed. ~$3500 (minus $500 state rebate)

BTU). ~$5500 (no rebate)

00 BTU). $8000

attic, ductwork in 3 upstairs closets, vent in EVERY room first & second f loor, return in upstairs hall. ~$7500. 1 year parts & labor, 10 years parts warranty.

rd any of these (I can), what would be the relative advantages/disadvantage s of each? How about the relative cost of operation?

ve to Antarctica.

I think so, too. But I'm concerned about the cost of operation. The guy yes terday said that with the mini split, you could let the house heat up quite a bit, turn it on and the room would be cool in a half hour or so. With th e whole house deal, he said that if you let the house heat up, it could tak e hours to cool off the house to 74 or so. So he recommends that you set th e thermostat to 80 when going out. So, that gets me thinking about energy u sage.
In reality, I work at home, so I'm here most of the day, but only in one or two rooms.
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On Wednesday, June 18, 2014 4:39:03 PM UTC-4, rangerssuck wrote:

l. I'm in Northern NJ, and it's getting pretty hot outside. I currently hav e not enough window units to keep the whole house cool, and I'm thinking it 's time to do something.

offered (and all of the pretty similar in price is:

n back yard under the window that now has the big AC, inside unit on living room wall. A couple of fans as needed. ~$3500 (minus $500 state rebate)

0 BTU). ~$5500 (no rebate)

,000 BTU). $8000

in attic, ductwork in 3 upstairs closets, vent in EVERY room first & second floor, return in upstairs hall. ~$7500. 1 year parts & labor, 10 years par ts warranty.

ford any of these (I can), what would be the relative advantages/disadvanta ges of each? How about the relative cost of operation?

move to Antarctica.

esterday said that with the mini split, you could let the house heat up qui te a bit, turn it on and the room would be cool in a half hour or so. With the whole house deal, he said that if you let the house heat up, it could t ake hours to cool off the house to 74 or so. So he recommends that you set the thermostat to 80 when going out. So, that gets me thinking about energy usage.

or two rooms.
I don't think there isn't anything magic about one system cooling the house faster than the other. And I would think 3.5 tons in a 1500 sq ft house is going to cool it off pretty quickly, unless it's poorly insulated, has a lot of sun exposure through windows, etc. I can't imagine it taking hour s. And just an hour can already make a big difference in the perceived temp, because it takes out the humidity. Sometimes I put on my system because it's 75, but it's too humid. In just 20 mins or so, you can feel a differe nce in the humidity.
There is a difference though in energy usage if you just cool one or two rooms with a mini-split or cool the whole house.
The good news is that these systems are a lot more efficient than they were 20 years ago. A 14 SEER system on a 1500 sq ft house shouldn't cost that much to run. You can keep the house at 76, and with the reduction in humidity, I find it quite comfortable. I think the difference in electric cost isn't going to be that great, and if you make a decision based on that, it would be a mistake. Plus in NJ, it's only going to be used substantially for 3 months of the year.
BTW, in comparing those systems capacities, one ton is 12K BTUs.
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On 6/18/2014 6:46 PM, trader_4 wrote:

And, here is your chance to tell us all what "one ton" is.....
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On 6/18/2014 1:39 PM, rangerssuck wrote:

you could let the house heat up quite a bit, turn it on and the room would be cool in a half hour or so.
With the whole house deal, he said that if you let the house heat up, it could take hours to cool off the house
to 74 or so. So he recommends that you set the thermostat to 80 when going out. So, that gets me thinking about energy usage.

Didn't say it couldn't be a split system...just that you'll probably regret not being able to cool some other room in the future if you don't allow for it. And you can still have some combination of window units for less-used areas.
I had the house weatherized back when stimulus money was available.
The thermal time constant of the house is longer than the time I'm away. Takes almost as much energy to reheat/cool the house as I saved while away. And that's MEASURED info, not some random guess.
Insulation is your friend.
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On 6/18/2014 4:39 PM, rangerssuck wrote:

of operation. The guy yesterday said that with the mini split, you could let the house heat up quite a bit, turn it on and the room would be cool in a half hour or so. With the whole house deal, he said that if you let the house heat up, it could take hours to cool off the house to 74 or so. So he recommends that you set the thermostat to 80 when going out. So, that gets me thinking about energy usage.

day, but only in one or two rooms.

I can see advantage to cooling two rooms -- you don't get the heat gain through the rest of the house. Might be cheaper in the long run.
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On Wed, 18 Jun 2014 09:00:45 -0700 (PDT),

You might consider improving the insulation factor on the total house as the first step. If this house has never had proper insulation the lack of insulation may be a major factor in comfort.
You might also wish to consider mounting the air conditioning unit on the roof to at least slow if not prevent theft of the equipment. One other positive result from roof mount is the water runoff could be spread across the roof to help cool the house through evaporation.
You might also wish to consider just cooling the upper level to start. Cool drops/ heat rises.
Or just give up air conditioning all together and learn how to best vent the existing window system for the most comfort.
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Vandy Terre wrote:

Hi, +1. W/O taking care of windows, insulation, there is no sense in wasting energy running a/c. I were in that situation a/c is priority no. 2.
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