UPS for Pellet Stove - does it have to be super strong?

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Jan 30, 2021
14
Northwest Arkansas
I see Hartman’s approved units are 750 Watt units - anything special about that number? doesn’t seem possible that these stoves can use that much. Curious on your thoughts. I’m looking for a UPS that doesn’t look like a space ship or ugly since our stove is in our living room :).
 
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Spec says Max watts is 516@120VAC 60HZ. I don't know anything about what those mean, but would expect that since it cycles the combustion blower, that it would hit max every couple of seconds. Will a 600 work? I don't know.

Unfortunately, Schneider Electric (makes APC) seems to have discontinued the little 750 UPS that was just a bit bigger than a standard surge protector. I use those on my stoves and they would go on sale regularly for $80. I'll have to replace mine soon since they are 5 years old.
 
The UPS doesn't run the stove it just supplies enough power for a proper shutdown. That might take 45 minutes so you need enough reserve battery to do this.
Ron
 
Harmans run at about 450 watts or less at start up w/ igniter on. I use a kill-a-watt meter to quickly diagnose igniters. at startup if it is pulling 425-450w igniter is good. If it is pulling 425-450 and auger not turning, auger motor bad or jammed. If 125w or so, and no auger stove plugged up. 125w and auger turning igniter bad. Everybody with a stove should have one. Makes diagnosing issues alot easier without having to take anything apart.
 
I use a clamp meter myself versus a Kill-a-watt. As stated a UPS is only for abnormal shutdown) not for operating any stove.
 
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Killawatt is handy especially on inserts where it is tough to run it out of the hole. No panels need removed for quick diag
 
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The UPS doesn't run the stove it just supplies enough power for a proper shutdown. That might take 45 minutes so you need enough reserve battery to do this.
Exactly. Mine will run on UPS for an hour, gives me time to get the generator running... I then unplug the UPS, plug it into my generator and I'm good without stove shut down..
 
Why I don't need or want one. 45 seconds after utility dropout, I'm back online which isn't even enough time for the stove to hiccup. Only thing impacted ate the electric clocks and the microwave memory. Not even the laptop is impacted, has it's own built in UPS, called a battery.
 
I would suggest that using a UPS or generator is not a good idea on any pellet stove to run it for any length of time. A UPS for a shut down is fine to keep the smoke from invading the home. A generator (not a big one but a small portable one) or most UPS's are not a pure enough sine wave to power pellet stoves. Most if not all computer boards (for a lack of better description) in these stoves do not do well with generator or UPS power. You are better off running your other source of heat when power is out off the generator. In my case the forced hot water oil heat works well. The burner has no issues off the generator. Pellet stove boards are not cheap. If your don't have another source of heat well...sorry.
 
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Maybe Sysko can clarify this but, don't most UPS units have modified sine wave inversion anyway?
 
I agree with the reasoning to only use to power down your appliances. but most LineInteractive UPS"s are designed to run PSW and will correct under voltage down to 92vac and over voltages up to 150vac with built in protection. so they could be connected to a generator and be used safely

 
This is a topic I've come across just recently. Apparently it's the wave form, noise, distortion.... all of them. There's very little clear information I've found on all of those items. The only way to find out seems to be testing your product of choice with an oscilloscope. Since I don't have one or know how to use one I'm at a bit of a loss on what might actually be sufficient to protect our circuit boards.

I certainly DO NOT trust what little incomplete information the manufacturers provide.

There's always an inverter generator but at 3-5x the cost I'd still want to test before trusting the quality of their power output.
 
So I'm curious, and interested in the answer to the OP's question since I have to replace mine soon. I don't see an answer to the actual questions, does it really need to be 750W for a Harman?

Many of us have a UPS that is designed only as the emergency shut down unit and as a surge protector, so we aren't trying to power the stoves thru a power outage (which by some of the answers, seems to be what has been assumed). But, it seems that anymore, those types of units are 600w or lower and you have to go to a big battery unit to get what is suggested in the manual (and even this one, is only 700 - not 750)

Maybe someone actually did answer the question, but it was in such a manner thatI am not smart enough to understood whether it meant a yes, or no.
 
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Sorry bogie, the wattage is not just for the stoves wattage draw. It also is is an indicator/determination for battery type and size. UPS’s are actually designed for Computer/server interruption protection not really stoves. So if you want a ups for emergency shut down a 450 would handle the load but might not have enough storage to complete the task. The 750W would probably have enough battery to do it.
 
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I have been kicking around the idea of getting the small Honda knock off Predator inverter generator from China freight. But I know if it needs any parts on the future they probably are not available. For the little use it would get I hate to spend full Honda money...
 
I have been kicking around the idea of getting the small Honda knock off Predator inverter generator from China freight. But I know if it needs any parts on the future they probably are not available. For the little use it would get I hate to spend full Honda money...
Rick... Get a Campion from Generators Direct. I have the 2K watt inverter one and I use it in my RV and around the house when I need portable 110 ac power to run power tools.

The Champion is Chinese but built to their specification. It's a Lifan motor which is top of the Chinese heap, servo controlled throttle, auto idle down, quiet as a mouse and very frugal on fuel. and Champion has expendable parts like spark plugs and air filters available on the website (USA).

Very pleased with mine, it replaced a Yamaha inverter that was 15 years old.

I won't buy Honda power equipment. Over priced and I had a warranty issue on a Honda motor some years back (threw a rod) and Honda insisted it was my fault, even though the motor was only less than a month old. Needless to say that was it for Honda and me.

I recommend the Champion. Starts second pull every time too. Keep in mind that no matter what inverter you buy, the multi pole generator head will be a licensed by Yamaha product. Yamaha invented the multi pole dc head that is in all of them.

Mine is 5 years old, gets used a lot and is very reliable.
My issue with the HF Pred generators is like you, parts availability and because the inverters are electronic, no place to have it fixed if it does puke.
 
The big question is what risk are you willing to accept on your own in making this decision. No one here can do that for you or balance the aesthetic vs risk decision.

The bare minimum you want to do is add a good surge suppressor as many on this board seem to have had issues that they blame on ESD or EOS (Electrical over-stress). The basic rule is more is better.

When it comes to AC backup the group is split based upon the amount of run time required. However the rule above applies to each case and an advantage of a UPS is the surge suppressor may be integrated. When trying to run a stove on a UPS (including being able to start the stove) you will see posts stating you need a pure sine wave unit since the modified sine wave UPS's cause the stove to shutdown (a feature designed in by the stove manufacturer).

So lets say you want the bare minimum battery backup solution and your focus is to do an orderly shutdown after the stove has started. A post above and my experience is the stove may only be drawing 100W and shutdown time is 0.75 hr. This could imply you only need a 75W-H UPS which with power factors might be a 100VA (if you can find something this small). However consider that this would be totally depleting the battery on each shutdown cycle which reduces its life. Also there would be no guaranty that the stove doesn't need 1 hr to shut down based upon pellets being burned so lets say you increase this by a factor of 4 to be nice to the batteries and ensure theres sufficient shutdown time. Now we're up to 400V-A. And what if the power comes back during shutdown (causing the stove to feed) then goes away again with the batteries only partially charged? How much run time is left in the unit knowing you now need an additrional 45+ minutes?

For me the 750VA rating published by Harman provides a safety factor which they considered acceptable for the use case and life of the UPS batteries. I chose to go with a 1000VA to get the best surge protection in this class of UPS'.

Again, each owner must make the decision for themselves based upon the risk they are willing to accept. There is no hard and fast rule of what will work because each use case and requirements for the UPS may be different. If you want to experiment, consider the bare minimum to meet your needs, review the return policy on Amazon prime. But make sure you pay attention to the surge rating of the UPS you buy since control boards cost a lot more than surge protectors or UPS'.
 
Sorry bogie, the wattage is not just for the stoves wattage draw. It also is is an indicator/determination for battery type and size. UPS’s are actually designed for Computer/server interruption protection not really stoves. So if you want a ups for emergency shut down a 450 would handle the load but might not have enough storage to complete the task. The 750W would probably have enough battery to do it.

Thank you - that explanation makes sense to me.
 
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Rick... Get a Campion from Generators Direct. I have the 2K watt inverter one and I use it in my RV and around the house when I need portable 110 ac power to run power tools.

The Champion is Chinese but built to their specification. It's a Lifan motor which is top of the Chinese heap, servo controlled throttle, auto idle down, quiet as a mouse and very frugal on fuel. and Champion has expendable parts like spark plugs and air filters available on the website (USA).

Very pleased with mine, it replaced a Yamaha inverter that was 15 years old.

I won't buy Honda power equipment. Over priced and I had a warranty issue on a Honda motor some years back (threw a rod) and Honda insisted it was my fault, even though the motor was only less than a month old. Needless to say that was it for Honda and me.

I recommend the Champion. Starts second pull every time too. Keep in mind that no matter what inverter you buy, the multi pole generator head will be a licensed by Yamaha product. Yamaha invented the multi pole dc head that is in all of them.

Mine is 5 years old, gets used a lot and is very reliable.
My issue with the HF Pred generators is like you, parts availability and because the inverters are electronic, no place to have it fixed if it does puke.
That is very helpful, I dont know much about generators. I always thought the Champions were junk due to there low price. But I guess not
 
That is very helpful, I dont know much about generators. I always thought the Champions were junk due to there low price. But I guess not
Maybe the box store ones that aren't PSW units. I have no use for one of those but the Champion Inverter has been flawless for me and it's lightweight too. Mine will run all night on eco throttle when I'm camping and it's very quiet, cannot even hear it running. Comes with a USDA approved spark arresting muffler too. Important when in the woods. I plug it into the RV, run it on eco throttle and let it decide on how fast it needs to run, depending on load. My wife and I both snooze on CPAP machines and it handles both of them and the RV no problem. It don't make enough amps to start a roof mount ac but then in the woods, I don't run the ac anyway. keeps the batteries charged, the machines running and runs the coffee pot in the morning too. I recommend them from real world testing, by me.... and, you can parallel 2 if you require more power and Champion sells the parallel kit. Not something I require however. Like a small suitcase with outlets.

I don't like carrying excess gasoline along so I run mine on the chainsaw premix I use in my Stihl chainsaw (50-1 stihl pre-mix oil) and it's perfectly happy. I carry my chainsaw fuel and the bar oil in Rotapax 100% sealed containers. No leaks, no stink. we camp off road not in campgrounds. Have a slide in truck camper that fits in our Ford F350 diesel 4x4 pickup.... Bug out vehicle. Mostly on outrNorthern Michigan property that is only accessible with a 4 wheel drive via season road complete with water crossings.

We own 55 acres adjacent to the Manistee National Forest in Mecosta County. 100% old growth hardwood. Can spend a week there and see no one which works for me. I'm not a social butterfly anyway. Hunt there during season too. Loaded with deer, bear and assorted creatures.
 
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I also have a Champion Inverter 2000 watt generator also. Never had an issue with it, keep fresh ethanol free gas in it with stabilizer..
 
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I also have a Champion Inverter 2000 watt generator also. Never had an issue with it, keep fresh ethanol free gas in it with stabilizer..
I don't even do that. I just run the stihl pre-mix (has fuel stabilizer in it) and fire it up and run it regularly. It is sitting in the bed of the side by side presently in the heated shop.

E free gas is super expensive here, like 4+ a gallon. probably be 6 once the new administration gets done with their energy bs.

Never seen them in any box store being sold. Always the larger non PSW noise makers. Cabelas has them, seen them there but Generators Direct beats Cabelas price hands down and if I remember correctly, shipping was included.

Only thing I wish it had is an hour meter (my Yamaha did). Makes it easier to track oil changes, but I change mine every year and that seems to be sufficient, not that it hold a lot of oil anyway.
 
I have AIMS 1250 Inverter/Charger to power my stove in outages. That teamed with Two 100AH Batteries gives me 12 hours (Harmon XXV in Manual and Medium Fan Speed). https://theinverterstore.com/product/1250-watt-pure-sine-inverter-charger/

IMG_20210119_064818105.jpg
 
Aims Power make good units. I have a 3000 watt Aims Power PSW inverter with remote switching in my RV and it's flawless.
 
I don't even do that. I just run the stihl pre-mix (has fuel stabilizer in it) and fire it up and run it regularly. It is sitting in the bed of the side by side presently in the heated shop.

E free gas is super expensive here, like 4+ a gallon. probably be 6 once the new administration gets done with their energy bs.

Never seen them in any box store being sold. Always the larger non PSW noise makers. Cabelas has them, seen them there but Generators Direct beats Cabelas price hands down and if I remember correctly, shipping was included.

Only thing I wish it had is an hour meter (my Yamaha did). Makes it easier to track oil changes, but I change mine every year and that seems to be sufficient, not that it hold a lot of oil anyway.
There are hour meters that just have a pig tail that wraps around the sparkplug wire. E free gas here is usually 50 cents more per gallon than regular gas, & 90 to 92 octane..
 
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