From: DEHP@calvin.edu (Phil de Haan)
Subject: keep me warm baby!  a summary.
Keywords: furnace information
Organization: Calvin College
Distribution: usa
Date: Mon, 28 Sep 1992 17:26:14 GMT


First of all:  THANKS!  I received some great information on the net from 
people about furnaces.  As requested, I am sharing that information.

First, I decided, and most advised, to buy a higher-efficiency furnace.  
Ours will be 92% efficient.  In our case the difference in price 
between a 78-80% efficiency and a 92% efficiency will be paid for in four to 
five years.  We plan to live in our house for at least 10 years, so it made 
sense for us to pay a little more now and realize savings over a longer 
period of time.  If you plan to stay in your house a year or two (or maybe 
even three) it may be wiser to go with an 80% furnace.

Most heating and cooling companies can give you brochures that show you an 
average annual heating bill for 60%, 70%, 80% and 90% furnaces and those 
charts wil easily allow one to figure out savings per year.  You then 
can decide if you'll be in your house long enough to warrant a higher 
efficiency furnace.  Another factor in our case is that MichCon (our gas 
company) is now giving a $300 rebate on the purchase of a 90% furnace or 
higher.  That rebate makes the differnce in price between 80% and 90% a lot 
less and made our decision pretty easy.

One poster advised that it may be smart to go with an 80% furnace if it will 
be placed in a room you use, such as a finished basement.  He said he has a 
40-year-old unit and the "lost" heat goes directly into his basement thus 
keeping him warm.  I asked an employee of one of the companies that gave us 
bids about this and he said it's true of old furnaces, but that with the new 
furnaces there's no heat "lost" into the room.  The difference in efficiency 
comes with better heat exchangers, more efficient blowers, etc.  An 80% 
furnace will not leak 10% heat into a basement, while a 90% furnace doesn't 
leak any.

Most net wisdom seemed to advise an air induction system that pulls air into 
the house from the outside.  It is more efficient and healthier, especially 
if your house is very well insulated.  Most high-efficiency furnaces pull 
air from the outside.

In re: to heat exchangers, stainless steel seems to be a little better and 
more duarble than aluminum, but both are pretty trustworthy.  Most furnances 
today have pretty extensive warranties (like lifetime in a lot of cases), so 
it may not be worth it to pay more for a stainless steel heat exchanger.  If 
it comes with your furnace, you're probably better off.

A constantly burning pilot light is more expensive in monthly costs than 
electronic ignition.  One poster noted that just a constantly burning pilot 
light cost him $12 a month in gas service to an empty aprtment last summer.  
But electronic ignition is more expensive at first and more costly to repair.

Another factor that the net and heating and cooling companies talked about 
was vapor condensation.  An 80% furnace usually vents out the chimney and 
water vapor can condense inside leading to damage to the flue lining.  A 92% 
furnace vents out the side of the house via PVC pipe and uses a pump to 
remove water vapor to a floor drain.  If you have a floor drain by your 
furnace you don't even need the pump.  We don't so we need a pump.

That's about all that seems important.  I may have missed something though.  
If you have any questions send me Email and I'll try to help you out.

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 Phil de Haan (DoD #0578)                                       Every day
 Calvin College                                                        is
 Home of the 1992                                                    ride
 NCAA III men's                                                   to work
 basketball champions                                                 day
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++