Powering blowers on fireplace insert

bboulier · Feb 9, 2010

Thanks to all of the helpful information provided on this site, we are getting a Jotul 550 Rockland fireplace insert installed. Hearth.com is a wonderful site. The call for action was an expensive repair on a cracked chimney liner. Looks like we'll have to wait until the snow melts before installation. Timing could have been better! The old fireplace has (what I think) is a heatalator with a small fan that would heat the upper floors in a 1950s split level. I have a marine battery with inverter back-up for powering the small fan on the current set up. This latest snow and power outages set me to wondering what the amps of the blowers on the Jotul are. I can't find any information in the Jotul on-line manual. Does any one have this information?

Bryan

PNWBurner · Feb 9, 2010

I'm not sure what that blower draws, most are <1 amp. I notice that mine is much happier running on the sine wave inverter on my Honda generator. On a cheap square wave inverter/battery combo the blower gets buzzy and just doesn't sound too good although it does work. That's probably due to the rheostat so if you just have an on/off switch you might be fine. Either way they don't draw much power but they do run for a long, long time (constantly ideally) which can make sizing your battery a little tricky...

RobinJoe · Feb 9, 2010

I have a similar setup (a couple marine bateries and power inverter) as a backup for my Lopi Declaration. I have a related question:

Will the battery last longer if I set the fan to low speed and run it constantly, or high speed and only run it 1/4 of the time? In other words, does the rheostat reduce the efficiency of the system?

Thanks!

PNWBurner · Feb 9, 2010

Turning down the rheostat will reduce the draw on the battery but you still have to consider the idle current and efficiency of the inverter too. Some draw quite a bit of power just to be "on" regardless of how much they actually supply. In some cases the inverter itself may be consuming more power than the fan does on low. The size of your blowers and how hot the stove is also makes a difference in how high you want to run them too so you sort of have to look at the efficiency of the whole system including the heat source.

bboulier · Feb 10, 2010

Thanks for the help. The thread on "How many rooms can you heat..." indicates that each blower on the Rockland pulls 19 Watts, so that would be about 1/3 of an amp combined.

Bryan

Kilted · Feb 10, 2010

PNWBurner said:
Turning down the rheostat will reduce the draw on the battery but you still have to consider the idle current and efficiency of the inverter too. Some draw quite a bit of power just to be "on" regardless of how much they actually supply. In some cases the inverter itself may be consuming more power than the fan does on low. The size of your blowers and how hot the stove is also makes a difference in how high you want to run them too so you sort of have to look at the efficiency of the whole system including the heat source.

It depends if it is a true rheostat - wire wound power resistor with a center slider, or an electronic power control. If it is electronic then yes you will use less power, if it is a "real rheostat" then no you will not save power, just heat up the place.

For inverters and motors ALWAYS use a true sine wave inverter not a MSW - Modified Square Wave, that is what MSW really means. Just remember to cost the charger in. A battery and inverter is only 2/3 of the kit the other 1/3 is the charger. If you just throw any old cheapo charger you will be shortening the life of the battery, I know I've done it. Lead costs a lot of gold these days.

-- Brandy

Search

Search

Powering blowers on fireplace insert

bboulier

Minister of Fire

PNWBurner

Member

RobinJoe

New Member

PNWBurner

Member

bboulier

Minister of Fire

Kilted

Member

Similar threads