On Tue, 1 Feb 2011 11:36:40 -0800 (PST), " email@example.com"
Except anything big enough to run the furnace will NOT run on 12
volts. My 1kva units are 36 and 42 volts.
I do have an old 1kva inverter from a BELL service truck that runs off
12 volts and has a remote start feature (comes on when the load is
On Feb 1, 9:56 pm, firstname.lastname@example.org wrote:
Hmmm, I thought you were the guy that has the furnace with an ECM
blower that only uses as much electricity as a 100W bulb. If that's
true, then your furnace should be capable of being run off a UPS
connected to a car battery. The blower is the only load that amounts
to anything. The inital startup current for a couple
seconds will be larger, but still should be within the capability of
an inverter powered off a car battery.....
On Wed, 2 Feb 2011 07:17:55 -0800 (PST), email@example.com wrote:
Go crawl back under your bridge.
Your reading comprehension, as well as your evident technical knowlege
are both at about a grade 3 level, but your aggravation factor is over
The ecm blower in heat mode draws about (up to) 6.5 amps,plus the
inducer motor. (that's the numbers from my furnace - your current draw
Not sure what the hot surface ignitor draws, but that is not an issue
because it definitely draws less than the blower, and is never
energized when the blower is in the "heat" mode.
If the furnace draws 7.5 amps at 120 volts (nominal) the power draw is
900 watts.. Assuming the inverter is 98% efficient that is a draw of
about 76 amps from a 12 volt battery. And getting back to your
abysimal reading comprehension, not very many 1kva UPS units, which is
what was I was responding to, work off of 12 volts. Any that do are
"bottom feeder" models that would not stand up to long-term use at
If you have a AC motor blower the starting current of the blower is
generally well over 150% of nameplate current - so let's say you need
an "inverter" that can handle 1350 va motor starting power, with a
battery current exceding 100 amps on startup.
I am not aware of a 1.5kva UPS of any description that uses a 12 volt
And if you could find such a beast - and one that could run more than
20 minutes or so at full load without overheating, your average
automotive battery would be below 80% depth of discharge in
significantly under an hour of steady use.
On Feb 2, 9:58 pm, firstname.lastname@example.org wrote:
Yeah, forgive me for being confused. You've spent so much time
us how that wondeful ECM blower runs 24/7 and only draws 100Watts.....
I guess you forgot the part where that's only in fan only mode, where
fan barely moves the air. The other part of that 24/7, when the
is actually heating, it draws 8 times that. But wait, we're supposed
use a two stage furnace that spends a lot of time on lower output
so that furnace is firing a lot of the time. Some would say it
firing all the time during the coldest days. So there goes that
ECM blower that only uses 100W, 24/7.
Uh huh, according to you.... Last time I checked the poster was
about using a simple inverter, not a UPS. A full UPS was never a
requirement. But you do have a way of taking threads into your
own little world. But even playing by your rules, what's this,
I found in 2 mins with google?
Samlex TN-1500-112F, Off Grid Inverter, 1500 Watt, 12 Volt, Pure Sine
Wave, w/Solar Charge Controller/AC charger & Transfer Relay for UPS
Pay attention. He didn't say he wanted to use an auto battery. The
question was about using a marine deep cycle battery. And you can
get deep cycle batteries that will supply 150AmpHr. Use a couple
of them and you have an hour or two of furnace run time.
Economical or practical compared to a generator? No. But
not totally out of the realm.
I know you think you Canadians are very smart up there. So, I'm
sure you'll like this source straight from Canada. They say you
can power a furnace with a battery/inverter:
1A Battery backup with inverter/charger for short blackouts of 12
48 hours: $2,350 Essential AC loads only. Furnace, sump pump, well
pump, fridge, plus efficient lights and small DC appliances.
Again, I'm not saying it's cost effective, or practical. I'd go with
But it shows that once again, contrary to your shoot from the hip
comments, it can be done. BTW, have you gone down to the auto
parts store to see those batteries with the removable cell caps?
I don't know who said that, but it just isn't true. I use a trolling motor
on my boat, and have run the battery down to nearly nothing many times.
After a trickle charge for a day or two, it is ready to go again and
performs as well as before, time and time again, usually for three or four
Besides, the OP said a "marine battery", and you said a "car battery". Two
related and similar, but slightly different animals.
On Mon, 31 Jan 2011 21:31:35 -0600, email@example.com wrote:
One thing you can do is to recharge your battery from the car. I did
that after hurricane Charley to run a few inverters off of my golf
cart. I used the batteries and charged them from the car 2 at a time.
Now I have this gadget.
A whole week? I think a marine battery won't last two days with what you
plan to do with it. Think of what happens when you leave your 55W car
headlights on overnight.
A generator is probably a better bet for you.
On Feb 1, 10:30 am, firstname.lastname@example.org wrote:
Get a car battery and try it but I still think you will be
disapointed. I've seen things as simple as leaving an interior light
on overnight drain a battery to where it would no longer start the
car. I have a group 29 dual purpose bvattery in my boat just to deal
with sitting and running the radio. And I still limit that to a few
hours. A group 29 battery weighs about 60lbs.
On Jan 31, 10:31 pm, email@example.com wrote:
You ae not going to run anything for a week off of a battery you can
carry. Batteries as a backup power source are very limited. Enough
lithium batteries to be of any use will cost a small fortune.
If you need a week you need a generator.
I tend to agree. But, it all depends on what his definition of "small
moderate loads" is. If it's lighting a small 12V lamp for 10 mins at
time a few times a day and charging his cell phone via USB, then it
could last more than a week. On the other hand, for most emergency
power for home use, you'd want to also run more, like the
more lights, possibly the furnace, etc.
I can tell you with my cabin cruiser it had two dual purpose marine
batteries and you could pretty much drain them in less than 24 hours
of reasonable use. That included just lighting, running the
bathoom fan, radio, water pump, etc.
He should start by putting together by determining the running current
for all the loads and how long they each will be used. Then he'll
the required AmpHours and what size battery range he needs.
On Jan 30, 11:59 pm, firstname.lastname@example.org wrote:
Battery MUST be forever on a charger, like a trickle charger but after
a few years it will go bad.....
Marine batteries have short lives and short warranties.
Your probably better off to buy a new battery for your vehicle and use
the old vehicle battery for your back up needs. this costs less and
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