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Default HVAC questions...


"BuddyBiancalana" wrote in message
. ..
Live in Indianapolis, @ 1,700 sq. ft. single story ranch style brick house
built in the early 1950's with a crawl space and hot water/gas heat.
Central A/C was retro-fitted in the early 80's, with all the vents

insulated
and the duct work (the insulated flexible tubes/hoses) running in the

attic.

We paid $250-320 per month from December to March last year (yikes).
However, in spite of the prices being 25-30% higher that year than the

year
previous, our bills were about the same.

Why? Answer: 1.) I replaced the skirt under our front door (the previous
one was missing about 7 inches of it, so you could see light inside when
sitting in our car outside and 2.) there was a 6ft.x 6ft. square area in

our
attic (just above our bed in fact) that had NO insulation. Tossed some
(about 8 inches) of the fiberfill over it and it made a HUGE difference.

As
a result, our bills at least stayed flat compared to the year before.

Anyway, I was relating this to my neighbor, and he said he paid about $400
TOTAL last year for the same size house with same attachments/features.

The
differences? As follows:

1.) He insulated his crawl space by stapling insulation (R-13) just below
the joists along the rim board of the house and going down to the ground

of
the crawl space and out about 2 ft. He stated that the cold comes down

thru
the earth and also across out about 18 inches.

2.) He plugged up and insulated over 4 of the 5 grate vents that went to
the crawl space. The fifth he left open to let in some air flow. He
indicated the vents were originally put in to be in code in the 1950's,

but
that those codes are now obsolete and that you only had to account for 15
cubic ft. of air flow per minute per person, which is accomplished by the
following...

3.) He cut a 9"x14" hole in the floor near the center of the house and had
it vented to just above the grade in the crawl space. Apparently this
creates enough flow....also...the earth temp in the middle of the crawl
space of 56 degrees heats the cold outside air before it can come up to

the
living area. He also indicated that he runs a bathroom fan 24/7 to assist
in drawing the air flow.

4.) He "vented" his gas furnace (in the garage in both houses, his and
mine). He basically cut a 4 inch round hole in his garage window,

inserted
a dryer vent fitting into it and then ran aluminum flexible tubing from

the
window down onto the floor. He stated that this gives the furnace all the
oxygen it needs, while without this, with the garage being largely sealed,
it doesn't get enough oxygen and the gas flame has some orange to it. He
also said since the garage is on a slab, the earth's temp heats up that

air
(the garage has a radiator in it, though not a thermostat). Is this safe?

5.) He dialed down the temp of the water running through the system from
180 degrees to about 110 degrees. He said this causes his electric pump

to
run more continuously, but that it is designed for that and that it uses a
minimum of electricity. He also said this makes for a more even keeled
temp, in the system and all around in the living space. Safe?

6.) He also turned down his hot water heater from 140 degrees to 110.

Your thoughts on these are greatly appreciated if you are anything close

to
an expert or professional. I am considering implementing all of these.
Should cost less than $250 total, including retrofitting my garage window
for the vent and the insulation.

I also installed some magnetic vinyl over the two air intakes in the

ceiling
at either end of my house that are used for the a/c (when I lay on the

couch
underneath on of them in the winter, I can feel the cold air cascading
down). I figure if the AC isn't being used, why let warm air up there to
get cooled down and then fall into the living area? Also, should I use
these over the outflow a/c vents in each room in addition to simply

closing
them?

Finally, the thing I have the most doubt over is the plugging up the crawl
space vents, except one, then cutting the hole in the floor with a grating
on top of it.

I want to implement all these, but need a little reassurance that I'm not
putting my family at risk. He's on a "level pay" system with our Gas
company of $70/month, and just got his "settle up at the end of the year"
statement, which was accompanied by a check for $355 made out to him.

Nice.

Thanks.


We used to plug the crawl space holes with bales of straw in the winter, (on
the farm)
I always thought it had to do more with critters than heating the house. I
cover the ventulator on my roof in the winter.

The manufacture of the heater would know more about the fresh air needs of a
given unit. I know that ducting fresh air in for combustion is a good idea.
How ever 4 inches seems pretty small for a furnance. I have more than 20
square inches just for a 30 gallon water heater.