On Jan 9, 1:40*am, "Ed Pawlowski" wrote:
?
"DerbyDad03" wrote







OK, so let's toss this in:

Let's say I run an electric oil filled heater to keep my basement a
bit more comfortable, but don't turn the main thermostat down. *At
first blush, we'd assume it's costing me more, right?

I can't see any way that it would not cost more.
First, you're heating an additional space with electric. Second, even
if
all the heat made it's way to the rest of the house, you're generating
that
heat with electric, not your main fuel, which was oil or gas, right?
Given
the relative costs of those fuels, and even allowing for 100% eff of
electric
and say 80% for gas/oil, it's still almost always expensive to
generate the
same amount of heat with electric.



How do we factor in the heat that rises and both warms the sub-floor
(there'd be *some* radiant heat into the first floor, wouldn't there?)
and also enters the first floor through the kitchen door?

Sure, you get some benefit from some of the heat from the basement
electric heater making it's way to the rest of the house. But I would
bet
that it's not a very large percentage of the heat.



How do we factor in the fact that the basement air is now warmer and
when it gets sucked into the furnace around the filter slot, it won't
reduce the temperature of the air in the return as much?

If that's happening, I'd seal up those duct leaks. But yes, under
current
assumptions, that heat too is getting transfered to the rest of the
house.



While I'm sure it wouldn't completely offset the cost of running the
heater, it has to bring it down some, right?

Yes, but I wouldn't bet on it being much.


Finally, my furnace uses the basement air for the combustion air. Does
the warmer air help or hinder the combustion process?

I don't think it has any effect at all on the combustion process. But
using air
at say 70F instead of 60F means you do get a wee little bit more heat
out
of the furnace, so yes it helps too.


Still going to cost more. As the heat rises, the thermostat is going to be
satisfied and not call for heat so you continue to use the more expensive
electric heat. *Sure, the basement is more comfortable, but at a cost.

Hot air *going into combustion is slightly more efficient than cold air
going it. * I forget the number, but you can gain a few percent with enough
of a temperature rise of combustion air but all that warmed air you are
burning is being replaced by infiltration of cold air in the house anyway..
To increase the efficiency, duct in fresh air for combustion and do not use
the circulated heated air at all. That is the way all high efficiency
burners work today. *Required by code in some places.

The only way electric heat saves money is to greatly reduce the amount of
heated needed in unused rooms. *If you use the examples I used yesterday,
for every Btu of electric I'd use, I'd have to reduce the oil heat use by
twice that just to break even. *I tried it one month and it was a costly
experiment.

There are things you can do to improve efficiency, but there is no changing
the laws of physics. *You want heat, you pay for it one way or another.- Hide quoted text -

- Show quoted text -