Anyone run a battery backup for an Insert Blower.

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daveswoodhauler

Minister of Fire
Hearth Supporter
May 20, 2008
1,847
Massachusetts
Searched the threads, and found some topics on a backup power supply for a pellet stove.......but was curious to see if anyone has a backup in place for an wood insert/fan only. Mine is 1.8 Amps/207 Watts, and I use it at the halfway setting most often. Basically, looking for something that would run the fan for 2-3 hours or so. (Have a Lopi Answer insert....so without the blower there is not much heat output)
Thanks.
 
Appreciate the help. Sorry for the dumb question, but how does one charge the battery after using? Again, sorry for the nob question.
 
So you're looking to run 207 watts at half power for 3 hours? As some basic calculation:


running 100 watts / 50% inverter efficiency = 200 watts

200 watts /12 volts = 17 amps

17 amps x 3 hours = 51 amp hours

So you'd want a battery with at least 51 amp hours capacity. If you only intend to do this once or twice, you could probably get away with a battery of about 51 amp/hour capacity. If you intend to do it on a regular basis, you'd probably want to get a bigger battery(ies) so the discharge isn't as severe.

As for charging, it's roughly the reverse...A 5 amp charger will take about (51 Ah / 5A) = 10 hours to recharge.

During the last couple of ice storms, I resorted to a spare battery in the garage and/or pulled a battery out of a car to keep my insert fan running. I let the flame go out during the day and took the battery to work for a recharge...ready for the next night of heat.

If you plan to have a lot of power outage, it might be worthwhile to look at a 12V blower (or at least an axillary) then you can run straight off a battery with no inverter losses and maximize your battery power.
 
You really don`t need it. The insert still projects radiant heat out into the room. Do like we used to do with a family of 5. Break out the sleeping bags and roll them out in the room where the insert is located, nice and toasty.

Very boring though, you can only do so much reading under candle light,no channel surfing,no flushing the toilet when you are on a well system. And not too many radio stations can be pulled-in with that battery cranked radio.

But you will survive and won`t freeze to death. What more could you want :-/

You do have to keep a closer watch on your insert though. No blower, means it will run hotter.
 
I've a deep cycle battery under the gooseneck trailer. It charges off of the truck as I'm towing. Battery gives me enough power for lights inside & out for 4 days if I'm parked and at a show, with out restarting the truck (lights off during the day, natch, and at night when sleeping), plus more, I am sure.

Hmmmm, off to the drawing board ;-P
 
Keep in mind that automotive and marine batteries that are unsealed and use 'wet electrolyte' can be dangerous because they can produce hydrogen gas. The manufacturers will tell you not to use them inside. You can probably get away with it, however. A battery explosion is no fun. Much less chance of that if you have a small fan providing ventilation for the battery. This is particularly important if the battery is in some sort of confined housing. Don't let it build up hydrogen gas and then find a spark or other source of ignition. A better choice for batteries is the sealed, gelled electrolyte, lead-acid types- although they are not as cheap as regular car/boat batteries. Used with care, a deep cycle marine battery is probably your best choice overall. Just be real careful. The thought of one of those big batteries charging in a confined space near a running stove and fan sort of gives me the willies. :bug: I'd feel a lot safer putting the battery and charger outside and running a 120VAC line into the room with the stove fan. Or maybe keep them in the garage- with the battery fan- ventilated.

Also remember to be real careful when working near big batteries whenever the terminals are both exposed. Both top terminals and side terminals which stick out can be dangerous if you are lax around them. It can get real ugly if a screwdriver or wrench happens to fall across exposed terminals, or perhaps clip leads touch each other.
 
sonnyinbc said:
You really don`t need it. The insert still projects radiant heat out into the room. Do like we used to do with a family of 5. Break out the sleeping bags and roll them out in the room where the insert is located, nice and toasty. [snip]

Unfortunately, I did...I have water pipes located at the totally opposite end of the house, so I needed to get heat all the way back to them as well.
 
Cluttermagnet said:
The thought of one of those big batteries charging in a confined space near a running stove and fan sort of gives me the willies.

I'm thinking that discharging a lead-acid battery does NOT produce hydrogen (especially good inside the house). Hydrogen is only produced during charging. Correct?

I pulled the battery out of my volkswagen last year and bought a cheap inverter at Sam's Club when we had an ice storm and lost power for a few days. It ran at about half speed for about 6 hours IIRC. Welcome heat!

A family member across town had power, so I recharged over there each day. My two muffin fans (VC WWL) are probably a little lighter on the power draw than others (don't have the numbers handy). I've thought of Cozy's 12V fan idea and like it, but I'm too lazy to pursue it right now.

Heat output from my insert is very low unless I run the convection fan.
 
Mo Heat said:
Cluttermagnet said:
The thought of one of those big batteries charging in a confined space near a running stove and fan sort of gives me the willies.

I'm thinking that discharging a lead-acid battery does NOT produce hydrogen (especially good inside the house). Hydrogen is only produced during charging. Correct?
As I recall, it does take charging the battery to cause it to produce hydrogen gas. If you ventillate properly (fan- forced air through the battery enclosure) you can avoid building up enough hydrogen to risk an explosion. But charging unventillated in confined spaces is asking for trouble. BTW one of those little 80mm computer fans should be adequate in an enclosure with sufficient louvers. If I built up such a unit (and I may, one day soon), I'd have a 2nd, redundant fan next to the first, just to be sure.
 
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