Replacing Forced air gas furnace

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Topic by JayTay posted 02-24-2015 03:54 PM 6822 views 0 times favorited 5 replies Add to Favorites Watch
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1 post in 2246 days

02-24-2015 03:54 PM

ok so here’s the problem im having. just bought a house and the heater is not blowing very hard at all. call a service guy to look at it. he says the furnace was replaced with a smaller unit then what was original in the house. He thinks originally it had a 5ton unit and now has a 3ton (75000 btu unit). the reasoning behind this the the duct size. he said the duct size was for a larger unit with a much larger blower on it and that is was cheaper to replace the furnace then to redo the duct work.

what i need to know is:

1. is it actually cheaper to put in a new furnace? looked them up and can get a 120K btu unit with 2 fan speeds for about $1500 from lowes or Home Depot.

2. is it super important to match the a/c with the furnace? this is important because the larger a/c evaporator is still in the duct work. they had to make a new connection duct to hook the smaller furnace to the A/C coils.

3. is it better to buy a specific brand or should i just get the most efficient one i can afford?

would really like to get the larger furnace as that would allow me to hook the garage ducting back up so my work shop can be heated and cooled. but if duct work is cheaper….well you know.

View dbray45's profile


157 posts in 2515 days

02-24-2015 05:21 PM

1 . Yes – Some of the newer ones have variable speed and will adjust to load. They are more expensive but will save you a lot over 5-10 years
2. Absolutely
3. Get the best you can – with at least 1 year warranty

If the blower doesn’t match the A/C – it will kill your compressor (if it hasn’t already).

-- Love woodworking and fixing most anything

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Instantwater Heaters

1 post in 2117 days

05-21-2015 05:07 AM

nice job you are doing.

View VadimIzoita's profile


3 posts in 1920 days

02-01-2016 07:09 PM

Replacing for a new one would really cost you for some cash but, the replacement will be worth it. Have you tried checking out the warranty of your old furnace?


View bobtroy's profile


2 posts in 1185 days

12-07-2017 08:07 PM

thanks for the info, if you looking for information about attic insulation and cleaning visit this site

View yosyosb's profile


1 post in 1049 days

04-22-2018 06:50 AM

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