Older Home, New Furnace decision

Old 03-19-06, 10:22 AM
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Older Home, New Furnace decision

Beacuse I live in an older home (1900) I'm wondering about the benefits of some of the options provided by furnace manufacturers.

Does a variable speed fan that circulates air almost constantly benefit an older home as much as it would benefit a newer home? We have old insulation, old windows, and little to no insulation in our walls (as far as I can tell).

This question also for the idea of two stage heat.

We are planning on replacing the furnace and water heater now. Over time we have other insulation projects to consider but for now we think the furnace is the affordable/money saving route to take. Our current furnace is 60% efficient. We live in Minnesota-so this should save quite a bit at 30% better efficiency.

Thanks for ideas and input!
Old 03-19-06, 06:00 PM
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New furnace

In reality, the insulation & other envelope improvements will have a better return on investment than upgrading the furnace. If you upgrade the furnace to match the existing load, you could easily end up with a funace that is 2X too big & a bigger energy hog than the old furnace. The most efficient equipment out there would likely be a 2 stage, variable speed furnace. Few people actually run their fans 24/7 but those who do, claim more uniform temperatures thruout the house.
Old 03-19-06, 09:05 PM
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Grady made a good point.

If you must replace the equipement, PLEASE tell the dealer to figured the load calc for new windows and upgraded insulation! Otherwise, your furnace will be oversized.

Why do you need to replace?

Two stage, variable speed system will provide great comfort in your home.

I am in Mn as well, and I been happy with the comfort it provides.. 1968 Spiltlevel home, and both floor are the same temp.. I don't run my fan 24/7 in the summer..
Old 03-20-06, 06:56 AM
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Grady and Jay are absolutely correct. Do your insulation improvement projects first.Then have an HVAC pro provide a detailed Manual J heat/cool load calc for correctly sizing new furnace. Also have your ductwork thoroughly inspected as to overall condition, size and CFMs, supply/returns, insulation, etc.

My opinion.
Good LucK!

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