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New Gas air furnace added in stages?

Planning addition for son's home, involving gutting and rebuilding most of second floor. Want to eliminate brick chimney and need to re-size for added Sq. ft. as well as add central A/C. Downstairs 800 sq. ft. and upstairs (new) at 700 sq. ft. May need to do this in stages due to relocation and capital.
Was thinking of installing new basement furnace (side wall PVC vent) with new water heater (PVC vent also) running one zone (downstairs)for 1-2 years until upstairs addition is done and finished. At that point we would add outisde condensor for A/C and tie in second zone (upstairs) through separate upstairs feed and plellum.
Want to do sheet metal work myself to save labor costs for son. Is this a reasonable approach and do they make systems out there that can be installed in this manner? Would I need a secondary blower on the second floor? (coming up from basement, then double right angles, then single right angle into central hall ceiling distribution plellum.)

Re: New Gas air furnace added in stages?

Sounds like you have a good grasp of what needs to be done in what sounds like a major renovation.

This project would be an excellent candidate for you to work in conjunction & consultation with a heating contractor, where you would do the necessary carpentry work & much of the HVAC distribution ducting, & the HC could then install the heating plant.

(heating and AC installs are divided into the furnace/boiler or AC unit itself, and the DISTRIBUTION network of ducts, piping, convectors, registers, etc.; the major part of the labor & expense is usually in the distribution portion of the install).

I'm not asking you to actually HIRE a contractor at this stage, just to listen to how they would do the install.

Sounds like a LOT of work & there are numerous ways to approach & install various types of HVAC hardware.

If you should have 3 or 4 HVAC contractors over there to give you a free estimate on how it should be done, believe me, you will get 4 different plans.

One may involve forced hot air/AC with steel ducting; another may involve forced hot water with baseboard and a mini-split AC, or a condensing furnace/boiler that doesn't require any venting, except a condensate drain to the cellar floor drain; another may involve a Unico hi-velocity flex duct system that would provide heat & AC in the same 3" flex ducting.

All of these options are highly popular as ways of doing HVAC these days, the final choice of which way to go depends on minimizing the amount of major construction & installing quality equipment at the least cost.

Other issues:
a) whether the chimney should be removed; b) choice of furnace/boiler (condensing (expensive) non-condensing); c) use of side vent can cause problems with exhaust odors; d) your location (moderate climate, hot climate, cold climate); e) how long you plan to stay in the home; f) low-cost home equity loans at low interest from the bank are ideal solutions for many of these projects;etc.

If you remove the chimney you forego your option to install a less expensive furnace/boiler.

In other words, if your plans are not set in stone at this point, & you haven't done so yet, I would encourage you to involve a few contractors in a free evaluation of what needs to be done so you can get their point of view.

You could save big $$$ and lots of unnecessary work by remaining in the planning stage a while longer.

It's a good idea to create a paper file folder with the various plans and the dollar cost of each one, so you can make a final decision on the best one.

Also be advised that most towns require only licensed contractors do the actual heating plant install; this usually applies also to AC compressors, which have charged freon.

You can probably get a permit from the town to do all the other work, which would be the lion's share of the renovation.

Any photos would be helpful.

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