Need a fp insert with a blower that's solar friendly

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Missouri Mag

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Nov 2, 2016
5
MO
Hi all. New to the forum. I've been trying to find information online and haven't been successful so wanted to see if anyone here as some input:
We are in the process of installing solar in our home and replacing our old mid-70's Buck Stove due to age, inefficiency and the back of it buckling. We want to find an insert that has a blower/fan(s) that will use less than 50-60 watts per hour and that we can turn off or unplug if we need to depending on how much power is left in our battery bank. We want to keep the daily blower watt usage under 1500w. We want a non-cat insert. I like the hardiness of the Buck Stove, the ease, etc. I called a shop near us and the salesman is still looking through his inventory. He'd not been asked for this info before. The Buck 74 we were looking at uses 126.5 watts. Way too much. There isn't a lot of watt usage online available from all the different makers. So far, the only unit we've found is the Napoleon 1101 that has one fan in it that uses 46 watts. We'd like to be able to get at least a couple of options before going with that one. If we absolutely had to, we'd go with a freestanding stove but it will stick out oddly in front of the fp.

With going solar, we're not going to be able to use fans much to move the heat around. The thermal fans I've read about that can go on a freestanding stove don't appear to work with inserts. Wish someone would make an insert with a heat powered fan.
Thanks everyone-looking forward to your input.
 
Stick with inserts that stick out onto the hearth. They will convect better naturally with the blower off. The PE Super or Summit are good at this as is the large Osburn 2400 if extended all the way out toward the hearth. Or consider putting a rear-vented, freestanding stove in front of the fireplace if the lintel height is high enough. This could convect heat better throughout the house.
 
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This came up in a thread about backup batteries for insert fans a while back, same issue could not find a fan that draws little amounts of power so we can run on backup battery for long periods, the only solution was a couple 12v deep cell batteries and a 120v converter or Gas backup generators.

Could you possibly hookup 12v deep cell batteries tied to a 120v converter for the blower into the solar DC circuit to charge the batteries?
 
Also take a look at the Regency H2100. It projects out far onto the hearth for better natural convection. It has a 2 speed blower that is .92 amps at full load, but this unit can run a half-speed which may bring it down enough to fit your requirement.
 
Stick with inserts that stick out onto the hearth. They will convect better naturally with the blower off. The PE Super or Summit are good at this as is the large Osburn 2400 if extended all the way out toward the hearth. Or consider putting a rear-vented, freestanding stove in front of the fireplace if the lintel height is high enough. This could convect heat better throughout the house.

Thank you! I will check those out. We know we won't get the whole house heated. It's got 3 levels with the fp on the middle floor. I used a fan last year to try to move some warmth downstairs and also further on the same floor. Helped some but only into the halls-it didn't migrate into rooms much. The heat also doesn't go upstairs very well either-too many walls.
I don't think we can go much beyond the 60 watts. We already have our system getting ready to install and we probably aren't going to be buying additional batteries/chargers/panels. We're not looking for just a ups backup for when the grid power goes out but something that can function daily on the system we'll have.
We may have to go with a stove option. Trying to find something that will look good where it needs to go as well as be functional.
Thank you for the specific product suggestions-I am looking at each one now.
 
In order to have a simple install of a freestanding stove the lintel needs to be high enough. What is the height of the lintel?
 
I just saw this information recently in the manual for my Lopi Revere. I'll give you the entire rating if it helps.

125 CFM blower
Volts - 115
Watts - 21.4
Amps - 1.8
HZ - 60

The blower can easily be turned on and off or unplugged.

Our insert also sticks 10 inches out onto our hearth. We wanted something that would radiate heat even during a power outage, and it does.

My manual didn't have the information as an entry per se. It was included on the "Listing Label" page. Perhaps looking at similar pages or asking dealers to check listing labels may give you more informed answers.
 
I think you'll find that the blower watt rating that you might be able to get is likely for the blower running at full CFM. I would suggest buying a Kill-A-Watt meter and measuring the watt consumption at the lowest CFM setting for the blower - this is likely the speed you would run the blower at. I would estimate that this would be 1/4th the consumption at full CFM.
 
This came up in a thread about backup batteries for insert fans a while back, same issue could not find a fan that draws little amounts of power so we can run on backup battery for long periods, the only solution was a couple 12v deep cell batteries and a 120v converter or Gas backup generators.

Could you possibly hookup 12v deep cell batteries tied to a 120v converter for the blower into the solar DC circuit to charge the batteries?

We already have a bank of 12v deep cell batts that the solar will be charging and all the gizmos to change it to AC, hopefully by Friday. We have the capacity to have enough watts to cover the fridge, a couple of freezers (all of those to be replaced with low watt usage units in the next year or so). We were allotting no more than 30% of the total watts produced (1500 out of 4200) on the blower. And we probably aren't going to get even the 1500w we're hoping for as it'll be winter and cloudy more than in the summer. Definitely don't want to use a gas generator every day (our solar isn't a backup).
 
I think you'll find that the blower watt rating that you might be able to get is likely for the blower running at full CFM. I would suggest buying a Kill-A-Watt meter and measuring the watt consumption at the lowest CFM setting for the blower - this is likely the speed you would run the blower at. I would estimate that this would be 1/4th the consumption at full CFM.

I don't have a functional unit right now to test with a watt meter unfortunately. Not sure if I could do that at a store...? Somehow don't think so. Don't actually know anyone who owns an insert. :(
 
I just saw this information recently in the manual for my Lopi Revere. I'll give you the entire rating if it helps.

125 CFM blower
Volts - 115
Watts - 21.4
Amps - 1.8
HZ - 60

The blower can easily be turned on and off or unplugged.

Our insert also sticks 10 inches out onto our hearth. We wanted something that would radiate heat even during a power outage, and it does.

My manual didn't have the information as an entry per se. It was included on the "Listing Label" page. Perhaps looking at similar pages or asking dealers to check listing labels may give you more informed answers.


If my understanding is correct...and not saying it is!!...if volts X amps=watts then wouldn't 115 X 1.8 equal a lot more than 21.4 watts?
 
I double checked the manual, and I did get the decimals in the right place. I don't really know how to explain it. I just wanted to provide you the information that was available. Maybe someone who understands more precisely what an electrical rating conveys can jump in and explain.

I also just hoped that letting you know that this type of information was available online on the "listing label" or "listing tag" would help you in your research. I just looked up the Kuma Sequoia Insert and Blaze King Princess insert just to see if I could find the information, and I believe that the Sequoia was rated at 50 watts. (I don't know if you have any interest in a catalytic model, but that stove/insert touts that it uses a natural convection system to move air without a blower, so you might want to research.)

I think I've also read here that Pacific Energy products aren't as reliant on blowers as some others are. Our Lopi puts out good radiant heat since so much sits out in front of the firebox (which we particularly wanted), but we really do need the blower to get the best convection going to move heat. We bought the stove just to heat a large walk-out finished basement but discovered that we are able to use it to heat the main floor of our rambler/ranch as well but we do need to aid the convection loop.

I'm sorry not to be more help but hope this gives you at least some more information to research.
 
then wouldn't 115 X 1.8 equal a lot more than 21.4 watts?

Forgive my intrusion and the long post below, but you are correct about the math looking strange, though I believe the 21.4 watts is a misprint in the manual and the value is actually 214 watts. 21.4 watts is very low (think tiny desk fan power level).

When talking about AC electricity, watts are only an accurate measure of power needed for resistors such as incandescent light bulbs and heating elements. Power requirements for motors, transformers, and other complex devices are more accurately described by multiplying the voltage by the current, with units of Volt-Amps (VA).

Any source of electricity, whether it be a giant steam turbine generator plant or a small solar setup with inverter, must produce sufficient Volt-Amps to operate the devices connected to it. Electricity is metered and sold on the grid in kiloWatt-hours (kWh) but Volt-Amp-hours is a more accurate description of the energy required.

In the case of the fan, it takes 214 watts, but 120 Volts * 1.8 Amps = 216 Volt-Amps. I use 120 volts in my calculation, as using 115 volts would result in some unusual numbers below and need more explanation than is necessary. Regardless these results are good, as the two values match up closely despite being more than your power budget allows.

Dividing the Watts by the Volt-Amps gives you Power Factor, a unitless number usually between 0 and 1. This is a useful indicator of how nicely a device plays with the generating equipment. In the case of the fan 214 / 216 = 0.99 (or 99%) power factor, quite good. Beware other devices such as home electronics and fluorescent lightbulbs, which can have a power factor as low as 0.4 to 0.6, requiring nearly twice the expected amount of power to run. Higher quality computer equipment and most LED lighting usually has active power factor correction, extra circuitry to force the power factor back up above 0.9. Read the labels and bring a calculator to quickly determine which devices will make the best use of your limited energy stores and which will be wasteful.

Fans with continuously variable speed control (like a dimmer switch) are usually worse for power factor, as they can still take their full helping of Volt-Amps, even when they are turned all the way down. Fans with a handful of discrete speeds use a different method of speed control and will usually have high power factor at all speed settings. If you need to save every watt, blowers and fans that run directly off the 12V DC of the batteries may be a better option as these also eliminate the efficiency loss of converting DC to AC.
 
I just measured mine: 29 watts on low, and 54 watts on high.
I feel that an insert fan would be a good application for an ECM motor since it runs so much.
At one point I looked around, but nothing popped out to me as a replacement.
An ECM motor would probably be infinitely speed adjustable, and economical while doing it.
 
One option would be to use an ecofan or equivalent. It's heat powered and provides a gentle mixing of the air. That would put a 0 watt load on the battery bank.
 
The thermal fans I've read about that can go on a freestanding stove don't appear to work with inserts. Wish someone would make an insert with a heat powered fan.

TEG powered fans would be cool, maybe in the future with more efficient fans that will be a possibility and prices will come down. You are correct that the ecofans do not work well on inserts.

Check out this TEG unit: http://www.tegpower.com/pro7.htm

Not sure if something like this could be rigged UNDER the firebox on an insert, take out the squirrel cage fans and use something like this to blow air through the air shroud once they are released.

 
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They can work ok on inserts that have an exposed stove top surface like the HI2100. Not as good as the convective fan perhaps, but better than nothing and with no load on the house battery system. The idea of a stove top TEG powering a remote fan blowing into the bottom of the convective chamber of the insert is also a good suggestion, especially if the stove config allows it.
 
I would put my time and effort into extending the hearth and putting in a free standing stove.
If you can send pics and measurements of your fireplace maybe we can help with ideas around a free
standing stove options.

Also whats the house size and room size the stove will be in?
 
It got cold enough yesterday evening for us to fire up our Lopi Revere (I'll try to work on a signature at some point) with its accompanying blowers, and I measured the wattage. Its lowest setting was about 27, its highest about 78, with everything in between. We've run the stove and blower continuously (but with variations in speed) since last night and have used just over one kWh.

I'm not particularly recommending our model to you, though we are very happy with it, but I did want to confirm that the manual information I posted earlier is definitely not accurate but neither was the later post that suggested that the blower would use 214 watts (we watch our electric usage and knew it couldn't be that high).

If you start finding particular models that interest you (I know begreen has been pointing you to various options), I bet you could post a new thread asking someone with that model and a way to measure wattage to report it to you. You may not know people with inserts close by you, but I bet you could still get some of that information with a direct request here.
 
I have a similar situation - standalone solar with a 48V battery bank. We went with a freestanding stove primarily due to the fact that you do not want to be running anything electrical in the winter months if you do not have to. I do run a air exchanger 24/7, it pulls .9 amps. I also will use a ceiling fan when running the stove to distribute the heat, it uses 1.3 amps on the medium speed. I try to keep my night time electrical usage to around 6 amps in the winter months. If you do not use a generator to charge your bank during cloudy stretches in the winter, your system will eventually shut down. Consistent undercharging will also lead to sulfation, greatly diminishing your battery life. Get a little Honda EU 2000i and get your batteries to FLOAT at least once every 3 days during the winter.
You should do whatever you can to go freestanding so if you do shut down you will at least have heat and the ability to cook/heat water. I find that my fridge is my biggest energy consumer at about 4 - 6 amps. It will occasionally spike to 16-18 amps when defrosting and it always seems to perform that operation at night! Going with a DC fridge is my next move as well.
 
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