Remodel/Upgrade HVAC - Tiger, please help

13 years ago

I've studied here for two years and still need help (or hand holding). Oklahoma remodel, 1750 sqft ranch adding 1,000 sqft, reinsulating, new windows and doors, roof and all. All will be done to tighten up the house. No problems there.

The current 3 ton HP/handler have done an admirable job in the leaky house with aluminum windows - but we do have hot/cold spots, and I know the central return grill is undersized. Duct work in the attic is well insulated, does not leak and is all metal.

Friend HVAC guy likes the idea of replacing the current HP/handler with a 3 ton XL15i and VS handler w/ Tiger D. approved thermostat, cleaning up the duct work to resolve distribution issues and increasing the return. We would then use 12kBTU mini splits in each of the two big additions.

I really like the idea, but my only issue with the ductless units is condensate lines - a hassle no matter how I look at it - plus the extra outdoor units and lines.

The other "sharp" HVAC guy has done a knockout job of sizing and measuring, running software and all of the impressive stuff we know now to expect of a contractor. Comes up with 4 tons for the entire house (I agree), but...

...after all this, he offers up a XL15i 4TWX5048 mated with a 4TEE3F65 (he knew I don't need the tax credit), an 802 stat, no modification of the existing supply issues, expects me to modify the handler cabinet and wants to run one flexduct to each of the additions - off of a supply trunk which has supply issues anyway. Oh yeah, I offered up to do his electric also.

Wants $9,300 to do that.

I'm tired of beating contractors up. Help.

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Comments (3)

juliekcmo
13 years ago
can you get another opinion.

My gut reaction is that neither of these guys are interested in getting your overall ductwork to perform for the whole house.

Are the areas of addition close to each other, or far apart? If they are far apart, then their loads are likely very different (if one faces west, and one north, for instance)

Ask guy #1 why he doesn't want to put everything onto 1 system.
Ask guy #2 why he thinks he can put everything onto 1 system.

If that were me I would want some more info.
tigerdunes
13 years ago
kaib

don't put the cart before the horse.

with all the updating you are performing including tightening up your home's envelope, I would start with a professional load calculation both heating and cooling. Get load calc in writing and on the software letterhead. Review carefully. Make certain both heating and cooling design temps used both inside and outside are correct for you and your area's climate. No fudging here.

then I would do same for your ductwork system-supply,return, leaks,insulation qualities,size,etc. any issues with hot/cold spots in home should be addressed.
you have central return in existing structure? how many? if just one, I would add another return to improve airflow in original structure. One return in new addition should be sufficient.

your home is all electric?

I do not like the idea of the mini splits.

that would be starting point. equipment selection later.

IMO
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kaib
Original Author
13 years ago
Thanks...that's exactly my issue. Ain't nobody gonna do the right thing around here, and I'm exhausted with all the rest of the stuff going on. Of six contractors here, exactly five have blown me off.

The one really sharp fellow did a knockout Man. J and then quoted me really high without regard to my existing supply issues (the return I can handle, as I have to work on the cab anyway).

$10,000 for a single stage 4T HP, VS handler, heat strips into a decent existing duct system which needs just a few mods (in an open attic) is too much - expecially when I am doing all the electric, modifying tha handler cab and providing open walls for the lineset.

Maybe I'm just tired. Ya'll are great.

Remodel/Upgrade HVAC - Tiger, please help

Comments (3)

juliekcmo

tigerdunes

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Remodel/Upgrade HVAC - Tiger, please help

Comments (3)

juliekcmo

tigerdunes

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kaibOriginal Author

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kaib
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