Running pellet stove off a generator

[john193]

I'm trying to put together a backup system to run my mt Vernon ae incase of a power outage. I have a generac 3.5kW generator which is pretty basic, essentially a dumb generator. I know plugging in the stove directly is asking for trouble, so my thought was to bridge the gap by using a ups backup with some ability to "clean" the power coming to the stove. Has anyone gone this route? Any ups in particular i should consider? Or have alternate solutions? Ideally I would have bought a better generator but power outages are rare here, though Sandy was the exception. Thanks.

 

[kinsmanstoves]

The Mt Vernon AE is a AC/DC stove. use the DC plug. Some generators will not run pellet stoves.

Eric

 

[MikeNH]

I've been looking into this myself. I have a Generac XP8000E which is pretty good with power (<5% THD) and I feel comfortable enough running the TV, laptops, etc. Which model Generac do you have? Some put out cleaner power than others. I wish I bought a Honda myself but it wasn't in my budget at the time so I did what I could do.

That being said, I've been looking at APC ups...just something basic which would run the stove by itself for the 15 min or so that it would take me to start and warm up the generator. It would also run a couple of lights, the internet router (if the internet is still up), etc during the times the generator is not running. I'm thinking (I need to verify this) that it would also take care of the instantaneous voltage drop that happens when my well pump kicks on while on generator power. Someone with more experience may be able to chime in.

 

[Harvey Schneider]

The Mt Vernon AE is a AC/DC stove. use the DC plug. Some generators will not run pellet stoves.

The DC plug is an option that you can get from your dealer. The stove will run directly from a 12 V battery, but it runs in a manual ignition mode and with blowers set to quiet mode.
After hurricane Sandy, I got three days of run (actual run time about 45 hours) from a 100Ah marine battery. Power came back so It went automatically back to AC operation, but the battery was still good for more. YMMV

 

[WoodPorn]

Check the specs on any UPS you look into, filtered power is an option not a standard

 

[john193]

The DC plug is an option that you can get from your dealer. The stove will run directly from a 12 V battery, but it runs in a manual ignition mode and with blowers set to quiet mode.
After hurricane Sandy, I got three days of run (actual run time about 45 hours) from a 100Ah marine battery. Power came back so It went automatically back to AC operation, but the battery was still good for more. YMMV

Thanks for the run numbers, that's better than I thought. I could go this route. I'd need to invest in a battery charger. Do you have a second battery as backup for quick swap? Having a second battery would allow me to keep things going and charge the first one off the generator, I assume.

I don't know the model off the top of my head and have never plugged the stove in directly. It should theoretically work but haven't tried.

Ps paying $60 for that cable is highway robbery, it's easy to just make one.

 

[WoodPorn]

Thanks for the run numbers, that's better than I thought. I could go this route. I'd need to invest in a battery charger. Do you have a second battery as backup for quick swap? Having a second battery would allow me to keep things going and charge the first one off the generator, I assume.

I don't know the model off the top of my head and have never plugged the stove in directly. It should theoretically work but haven't tried.

Ps paying $60 for that cable is highway robbery, it's easy to just make one.

Parallel two batteries and increase your runtime. Just be sure to charge them separately.

 

[Harvey Schneider]

Thanks for the run numbers, that's better than I thought. I could go this route. I'd need to invest in a battery charger. Do you have a second battery as backup for quick swap? Having a second battery would allow me to keep things going and charge the first one off the generator, I assume.

Seventy pound batteries are too heavy for me to carry around so I have since created a battery bank that also runs a large inverter to power my deep well pump. The stove steals power from the battery bank. I have a little (800W) generator and a charge controller that I can use to restore the battery bank if the outage lasts too long for its capacity. The battery bank is normally maintained by a small solar panel and charge controller.
Yes, $60 is an outrageous amount to pay for what is about $10 in parts (of course you have to consider the cost of labor and retail markup), but the consequence of getting the wiring wrong are unacceptable (I am told that there is no reverse polarity protection) and at the time I had no information about how the cable is wired.

 

[Harvey Schneider]

Parallel two batteries and increase your runtime. Just be sure to charge them separately.

Why is it necessary to charge them separately?

 

[Shaw520]

Why is it necessary to charge them separately?

good question,... I run off two marine batteries inverted to ac,.... when they need charging I simple pull the Chevy K2500 up to the door with jumper cables to restore the bank. charge them the same way as a dual battery set up in a truck

 

[john193]

Seventy pound batteries are too heavy for me to carry around so I have since created a battery bank that also runs a large inverter to power my deep well pump. The stove steals power from the battery bank. I have a little (800W) generator and a charge controller that I can use to restore the battery bank if the outage lasts too long for its capacity. The battery bank is normally maintained by a small solar panel and charge controller.
Yes, $60 is an outrageous amount to pay for what is about $10 in parts (of course you have to consider the cost of labor and retail markup), but the consequence of getting the wiring wrong are unacceptable (I am told that there is no reverse polarity protection) and at the time I had no information about how the cable is wired.

Is there a schematic of the wiring available here? Not having much look with google.

 

[Mr. Spock]

A lot of good info already posted. So I will just pass along some additional notes.

Most UPS's wont condition power in terms of fixing THD on the line. They are intended to cover brown out (low votage) or filter spikes (surge suppression). Power conditioners that fix THD are generally very expensive. If you are just looking to keep the stove going until the generator is kicked in, size a ups appropriately to your stoves power consumption and the amount of time you need to get the gen up. Figures in some head room (extra run time). Fully discharging a UPS will shorten it's battery life considerably. In a addition beware of units that output a steped sine or modified sine. These inverter types will raise hell with motors and can damage or shorten the life of electronic devices.

I have never had issues running appliances or sensitive devices like computers off my Generac. If your Generac is capable of supplying power with harmonic distortion around 5% or less under load, I wouldn't worry about it.

If your looking for an alternative, the solar route has been mentioned. Since your stove has a DC option you can skip the cost of DC/AC inverter and connect a battery directly. In terms of clean power, it doesn't get any cleaner than DC right from a battery. As mentioned by previous members, there are many options to keep a battery charged. Just keep in mind most batteries that have a high Amp/Hour rating require maintenance. Cleaning and topping off water levels come to mind right away with the lead acid variety. Additionally lead acid batteries release gas when charged so they must be kept in a well ventilated area. Never charge a lead acid battery inside the living space of your home. However there are alternatives like AGM but at higher cost per Amp/Hr.

 

[Mr. Spock]

Why is it necessary to charge them separately?

good question,... I run off two marine batteries inverted to ac,.... when they need charging I simple pull the Chevy K2500 up to the door with jumper cables to restore the bank. charge them the same way as a dual battery set up in a truck

You don't. You size your charger according to the Amp/Hr rating of the battery(s). In the case of the dual bat truck setup the alt is bigger. If the charger is undersized it will just take longer to fill the bank.

 

[bonesy]

Here is some summarized info I got directly from APC. If you are using an APC BackUPS system, it will run on a generator as long as the generator is big enough to handle the load being put on it. This specific UPS will provide clean, pure sine power to the end device while on line. Of course they will tell you their systems are designed for computer type devices, but a stove will run fine on one if you spec the APC UPS properly as well as the generator.

So basically, as long as the generator is big enough and doesn't bog down on other stuff starting, which would cause the UPS to try to maintain power, you are good. If the UPS actually kicks on and provides backup, that is NOT pure sine unless you purchased one of the APC models that does provide pure sine even while on battery backup.

 

[john193]

Here is some summarized info I got directly from APC. If you are using an APC BackUPS system, it will run on a generator as long as the generator is big enough to handle the load being put on it. This specific UPS will provide clean, pure sine power to the end device while on line. Of course they will tell you their systems are designed for computer type devices, but a stove will run fine on one if you spec the APC UPS properly as well as the generator.

So basically, as long as the generator is big enough and doesn't bog down on other stuff starting, which would cause the UPS to try to maintain power, you are good. If the UPS actually kicks on and provides backup, that is NOT pure sine unless you purchased one of the APC models that does provide pure sine even while on battery backup.

Can you comment on the model no of the unit in question? This setup would be much cleaner and more ideal for me as opposed to the battery backup.

 

[WoodPorn]

Why is it necessary to charge them separately?

Sorry I should have specified....The likelyhood of the batteries being the same (unless bought new) is slim, The two batteries need to be fully charged before paralleling....see post 22 here:https://www.hearth.com/talk/threads/battery-backup-dummy.93773/ Ah capacity for the 2 batts sould be similar if not the same if you're going to do this.

Here is some summarized info I got directly from APC. If you are using an APC BackUPS system, it will run on a generator as long as the generator is big enough to handle the load being put on it. This specific UPS will provide clean, pure sine power to the end device while on line. Of course they will tell you their systems are designed for computer type devices, but a stove will run fine on one if you spec the APC UPS properly as well as the generator.

So basically, as long as the generator is big enough and doesn't bog down on other stuff starting, which would cause the UPS to try to maintain power, you are good. If the UPS actually kicks on and provides backup, that is NOT pure sine unless you purchased one of the APC models that does provide pure sine even while on battery backup.

Again, not all UPS' clean the power up unless purchased to do so. Dirty power in = dirty power out on the smaller UPS'
I believe APC Back UPS does not filter, however Back UPS pro does.

 

[bonesy]

Can you comment on the model no of the unit in question? This setup would be much cleaner and more ideal for me as opposed to the battery backup.

No specific model other then the APC "BackUPS" line of UPS's.

 

[bonesy]

Again, not all UPS' clean the power up unless purchased to do so. Dirty power in = dirty power out on the smaller UPS'
I believe APC Back UPS does not filter, however Back UPS pro does.

I am specifically referring to APC's "BackUPS" models. They provide pure sine wave power to the device connected as long as they are online. "Online" meaning there is some type of power going into the UPS. It doesn't matter whether they are on a generator, main power, two squirrells spinning a wheel. As long as they are online, they are providing pure sine. What I summarized came directly from APC, so this is according to them, not my opinion.

They do make another model (SmartUPS I believe) that will also provide pure sine when running on the battery backup as well.

 

[Harvey Schneider]

Is there a schematic of the wiring available here? Not having much look with google.

I have attached two views of the business end of the cable. Facing the connector as in the photo, Red (pos) goes to the upper right pin and Black (neg) goes to the upper left pin. The bottom pin is unused.
The workmanship is nice on the supplied cable but the battery clips are cheap but adequate.

 

[velvetfoot]

I have since created a battery bank that also runs a large inverter to power my deep well pump.

I have to say that I'm very impressed. I had to upsize from a 5kw generator to a 7.5/13.5(surge) kw generator because the 5kw unit choked on the well startup current. Now, my well is 450' deep and the pump isn't a fancy soft start or anything.

 

[john193]

I have attached two views of the business end of the cable. Facing the connector as in the photo, Red (pos) goes to the upper right pin and Black (neg) goes to the upper left pin. The bottom pin is unused.
The workmanship is nice on the supplied cable but the battery clips are cheap but adequate.



View attachment 88995View attachment 88996

Many thanks. And I owe you a beer for not frying my stove.

 

[Harvey Schneider]

I have to say that I'm very impressed. I had to upsize from a 5kw generator to a 7.5/13.5(surge) kw generator because the 5kw unit choked on the well startup current. Now, my well is 450' deep and the pump isn't a fancy soft start or anything.

I went through three inverters (progressively larger) until I got an Aims 5kW continuous, 10kW peak inverter. Even then it takes at least two batteries in parallel to handle the startup of the well pump. With one battery the inverter input dropped to the inverter under-Voltage lockout during startup. The pump is 3/4 hp and the well is 425 ft deep.

 

[Mr. Spock]

The Smart-UPS line does have pure sine models. I don't know the wattage rating of your stove but I will assume 175 watt average draw. Throw in an additional 20 watts for the internal function of the unit ( inverter efficiency nor the batt amp/hr rating is stated in the specs so 20 watt loss is being chosen from experaince). A 600 watt model like the one below would provide approximately 30-40 minutes of run time at a 175 watt draw. To increase the life span of the battery however you do not want to discharge a lead acid battery more than 50%. So with the 600 watt model you would have about 15-20 minutes without severely discharging the battery. So that should give you enough time to get the gen up if it's being cranky for some reason or in worst case get the stove shutdown. Running just the fans you ( no auger) will reduce the watt draw somewhat so you may be able to squeak out 30 minutes on a 600 watt device.

My observation based on the information that is provided in the specs. I can not guarantee it's accuracy or the quality of the unit. DYODD!

Others may have some experaince with the unit.

http://www.bhphotovideo.com/bnh/controller/home?O=&sku=887745&is=REG&Q=&A=details

 

[Mr. Spock]

I went through three inverters (progressively larger) until I got an Aims 5kW continuous, 10kW peak inverter. Even then it takes at least two batteries in parallel to handle the startup of the well pump. With one battery the inverter input dropped to the inverter under-Voltage lockout during startup. The pump is 3/4 hp and the well is 425 ft deep.

If you have not already, consider a soft start pump (variable speed) if replacement ever becomes an option. Much easier on the power system and smooth water pressure too. Still need those amp/hrs to keep it going though.

 

[bill3rail]

I ran my Englander through Hurricane Sandy on a genny with not problems at all.
I do like the idea of a UPS so I can shut down the stove to get the genny running, and will look into it.

Bill