OWB battery backup....

[lapeer20m]

Last year my wife and i went a total estimated 168 hours without grid power. 5 of those days were brutal as it was late December and temperatures were near zero. I have a generator, but sometimes we loose power when i'm not home, or during an extended outage we have to leave home and go to work and there is nobody to watch the generator or fill it with fuel.

To bridge the gap between generator and grid power, I am getting ready to install a battery powered computer backup UPS (uninterruptable power supply)

I found a used one for $50 that is rated for 1,500 watts and uses a 12 volt battery. It produces pure sin wave and it has built in over/under voltage correction. I plan to connect the UPS to an "automotive type" deep cycle battery or 2. (or maybe a pair of 6 volt golf cart batteries) I am also in the process of purchasing two new alpha 2 pumps for my boiler system.

It will be fun to do some testing, but I am hoping for 10-20 hours of run time on battery power.

The load will consist of a pair of alpha 2 circulators, a transformer, and the boiler draft control.

I think this will be a great addition to my OWB system.

Does anyone have any comments or suggestions before i jump in with both feet?

I will take photos of the install.

 

[UpOnTheHill]

UPS's are expensive. Is your draft control electronic (sensitive to clean power)? Would a deep cycle battery and an inverter do the same job? The pumps should work fine on an inverter along with your controls transformer but I'm not sure about the draft control.
I sure would love an OWB to heat my house, shop and domestic hot water but when the power goes out you can't beat a freestanding woodstove IMO.

 

[lapeer20m]

UPS's are expensive. Is your draft control electronic (sensitive to clean power)? Would a deep cycle battery and an inverter do the same job? The pumps should work fine on an inverter along with your controls transformer but I'm not sure about the draft control.
I sure would love an OWB to heat my house, shop and domestic hot water but when the power goes out you can't beat a freestanding woodstove IMO.

A new ups may be costly, but used they are nearly free. Many smaller ones are $15-20 on craigslist. I found a large 1,500 watt ups for $50 bucks. I will spend 100 dollars on a deep cycle battery.

It's tough to find a cheap pure sine wave inverter, plus the ups will automatically switch to battery backup in the event of an outage even if nobody is home. Finding an inverter with this capability in the same price range that is not a modified sine wave would be difficult.

My draft control is 24 volts ac. Assuming the transformer is happy there shouldn't be any problems. Since a UPS's are engineered specifically to power computer transformers I think it will be a non issue.

 

[UpOnTheHill]

A new ups may be costly, but used they are nearly free. Many smaller ones are $15-20 on craigslist. I found a large 1,500 watt ups for $50 bucks. I will spend 100 dollars on a deep cycle battery.

It's tough to find a cheap pure sine wave inverter, plus the ups will automatically switch to battery backup in the event of an outage even if nobody is home. Finding an inverter with this capability in the same price range that is not a modified sine wave would be difficult.

My draft control is 24 volts ac. Assuming the transformer is happy there shouldn't be any problems. Since a UPS's are engineered specifically to power computer transformers I think it will be a non issue.

Sounds like you've got it mostly figured out. Let us know how it works!opcorn:

 

[blakey]

We

Last year my wife and i went a total estimated 168 hours without grid power. 5 of those days were brutal as it was late December and temperatures were near zero. I have a generator, but sometimes we loose power when i'm not home, or during an extended outage we have to leave home and go to work and there is nobody to watch the generator or fill it with fuel.

To bridge the gap between generator and grid power, I am getting ready to install a battery powered computer backup UPS (uninterruptable power supply)

I found a used one for $50 that is rated for 1,500 watts and uses a 12 volt battery. It produces pure sin wave and it has built in over/under voltage correction. I plan to connect the UPS to an "automotive type" deep cycle battery or 2. (or maybe a pair of 6 volt golf cart batteries) I am also in the process of purchasing two new alpha 2 pumps for my boiler system.

It will be fun to do some testing, but I am hoping for 10-20 hours of run time on battery power.

The load will consist of a pair of alpha 2 circulators, a transformer, and the boiler draft control.

I think this will be a great addition to my OWB system.

Does anyone have any comments or suggestions before i jump in with both feet?

I will take photos of the install.

I believe these units run on 24v so you would have to run 2 batteries in series.

 

[zogger]

In the alt energy community, these smaller units for home computers are not considered adequate for high demand loads, and don't take well to batteries larger than the smallish internal ones they come with. I do not know the electrical reason why not, but I have read this numerous times, as it comes up frequently when people are starting out with solar or wind, etc., and the smart guys always go no.

A proper charge controller and inverter for high demand use will cost more, but will do the job and you can use a much beefier battery bank. And the battery bank should be in a battery box with a vent fan set to push the air through and vented to the outside.

I maintained and lived off of a 35 panel and double quite large battery bank system (36 total) for almost five years before, at the place we were caretaking. The installer was talking to me about this very thing, as at first thought it seems reasonable so I asked him about it, and since then have read more about it.

My personal small system now is all 12vdc so I just have a charge controller.

 

[NSMaple1]

I would also be leery about the small UPS having the durability in its charging circuit to handle added batteries. That's a significant uppage in current through.

I got a 2200va UPS here last year for basically the same purpose. The thing is huge, weighs almost 150 lbs. Half of that is batteries. This one has a fan running inside all the time it is plugged in (indicative of it's heavier circuitry), which I didn't realize at the time - so I only plug it in & use it when I won't be home when burning or the weather is threatening an outage. But it is much more serious that the 1500va you have and that I was also looking at before I found the 2200.

But I am curious how it works out if you go ahead with it, so keep us posted. I wouldn't add whole lot of bettery to it though, at least at first. I think if I didn't find the 2200, I was leaning to looking at an inverter type setup also, the more researching I did.

 

[lapeer20m]

I found a more industrial ups that was 3000 watts for the same price. It utilized a 30 amp twist lock plug for the wall outlet and was designed to add a more robust battery pack via a plug that looks similar to those used on electric fork lifts.

The deciding factor for me was the input voltage is 48 vdc. Since I want oversized deep cycle type batteries and would require 4 at a cost of about $100 each, it elevated the price point above what I am willing to spend.

The electrical load is likely under 100 watts, so a 1,500 watt ups (I think it's actually rated for only 900 watts on battery power) in my mind should be more than sufficient for my needs. I'll be the first to admit that I am not that educated on the subject but I love repurposing "junk" and a ups with a dead battery is essentially garbage to most people and corporations.

 

[NSMaple1]

Ha - I also found a 3000VA UPS when I was looking but went with the one I got. Thing was even bigger than what I got, and I didn't have a 30a receptacle to plug it into - so I passed. Although likely should have got it anyway at the price he wanted, 'just to have'. The one I got has a 20a plug. It will also accomodate add-on batteries via the same plug setup. Just wish the fan on it wasn't running all the time it's plugged in - does it even when not turned on. A bit irritating since I have it up on a self (it's a rack mount) on the ceiling joists, right under my favourite living room recliner. Was lotsa fun getting it lifted up there.

Be sure to update - especially with what you come up with run-time for your circ, and mods you do to it.

 

[lapeer20m]

Ha - I also found a 3000VA UPS when I was looking but went with the one I got. Thing was even bigger than what I got, and I didn't have a 30a receptacle to plug it into - so I passed. Although likely should have got it anyway at the price he wanted, 'just to have'. The one I got has a 20a plug. It will also accomodate add-on batteries via the same plug setup. Just wish the fan on it wasn't running all the time it's plugged in - does it even when not turned on. A bit irritating since I have it up on a self (it's a rack mount) on the ceiling joists, right under my favourite living room recliner. Was lotsa fun getting it lifted up there.

Be sure to update - especially with what you come up with run-time for your circ, and mods you do to it.

I have had several inverters over the years, and at least three had fans that ran all the time. 2 of them were smaller and I simply cut the wires to the fan without ever suffering an overheat failure. I used these inverters inside a party bus that I pretty much lived in on the weekends.

I'm sure there is a small simple thermostat or temperature controller that you could purchase from eBay or amazon and wire into the fan circuit so it only runs when needed.

 

[lapeer20m]

I just ordered the pair of grundfos alpha pumps today. Some people claim that these consume as little as 7 watts of electricity while running.

I don't know how much power the 24vdc transformer consumes but I imagine it is less than 50 watts.

That's all I'm trying to run, two pumps and an hvac transformer.

I also do not know the efficiency rating of a typical smart ups vs a pure sine wave inverter....or a modified sine wave inverter....or the actual number of hours that a "group 31" deep cycle battery will produce 5-10 amps of current without damaging the battery.

 

[UpOnTheHill]

I used these inverters inside a party bus that I pretty much lived in on the weekends.

Did you say party bus? Lived in on the weekends? That sounds like a good time to me. Less talk of sine waves and more talk of party buses on the weekends. Got any good stories?

 

[bayard]

during a aquastat failure last year,i set up a on off timer 7 min off and 2 -3 min on with my groundfos.the pump speed was 1500 rpm . this took a few hours to set up.it took 3 days to find the right aquastat.40 year old aquastat.but long term a few big batteries and a good inverter would work as back up for the circular pump.mainly to shut the generator off at night.

 

[lapeer20m]

For a generator I use a honda eu2000 inverter type. This will run nearly my entire house sans washer/dryer, dishwasher, electric stove, and water pump.

During a 5 day outage we consumed only 10 gallons of fuel for continuous electricity.

I have a bigger Honda old fashioned type generator I purchased recemtly just to run the well pump. It will truly run the whole house (although not everything all at once) but is noisy and not nearly as fuel efficient as my little genny.

The problem we were faced with is the wife/kids going to her parents house while I went to work. There was nobody home to refill the generator and the temperature was below zero.

That's where the ups should play a roll in bridging the gap between running out of fuel And me Getting home from work.

 

[lapeer20m]

Did you say party bus? Lived in on the weekends? That sounds like a good time to me. Less talk of sine waves and more talk of party buses on the weekends. Got any good stories?

Did I mention the bus had a full size jacuzzi inside? But I digress...

 

[UpOnTheHill]

That's a what I'm talkin bout! I think that's my ex-girlfriend! Lol

 

[timbrjackrussel]

I just ordered the pair of grundfos alpha pumps today. Some people claim that these consume as little as 7 watts of electricity while running.

I don't know how much power the 24vdc transformer consumes but I imagine it is less than 50 watts.

That's all I'm trying to run, two pumps and an hvac transformer.

I also do not know the efficiency rating of a typical smart ups vs a pure sine wave inverter....or a modified sine wave inverter....or the actual number of hours that a "group 31" deep cycle battery will produce 5-10 amps of current without damaging the battery.

http://www.mkbattery.com/documents/3701MK_AGM_LG_v3_r8.pdf
The shallower the depth of discharge the better on any lead acid battery. Look at the MK or Deka battery site, lots of info.

 

[NSMaple1]

I just ordered the pair of grundfos alpha pumps today. Some people claim that these consume as little as 7 watts of electricity while running.

I don't know how much power the 24vdc transformer consumes but I imagine it is less than 50 watts.

That's all I'm trying to run, two pumps and an hvac transformer.

I also do not know the efficiency rating of a typical smart ups vs a pure sine wave inverter....or a modified sine wave inverter....or the actual number of hours that a "group 31" deep cycle battery will produce 5-10 amps of current without damaging the battery.

You will love those Alphas. I love mine.

I replaced my 15-58 3 speed zone pump with one a couple years ago. They should be required equipment in any system that has varying loads - constant speed pumps are woefully inadequate after using one of these . You can valve your flows down to what you want and the pump slows itself down to match - no more dead heading type stuff.

Has a digital display that shows GPM & Watts. I forget what mine shows, and don't know how accurate that is - but it's a lot less than what any non-ECM pump like the 15-58 uses.

 

[lapeer20m]

The pumps have arrived. I hope to get them installed tomorrow.

My father in law who is an electrician did not believe me when I said that others are consuming as little a 7watts with the alpha. I pulled one out of the box and it reads right on the label that the min power consumption is 5 watts.




I also purchased the 1500 watt smart ups. Unfortunately it turned out to be 24 volt instead of 12. This means that this project now requires $100 more than what was budgeted so I won't be able to purchase the 2nd battery right away. Too many other irons in the fire!

 

[lapeer20m]

The system may draw an average of as little as 25 watts. 7 for a circulator that runs continuously, 7 for a circulator that runs when the house calls for heat, a few for the transformer, and a little loss through the ups.

On a 24v system that's only 1 amp. trolling motor batteries should be able to provide 1 amp for quite a few hours.

I'm considering a pair of these walmart batteries. They have decent reviews and their return policy is pretty awesome with a 2 year free replacement. They are apparently 100 ah.

http://mobile.walmart.com/ip/EverStart-Maxx-Group-Size-29-Marine-Battery/20531539

This chart from a link posted above, indicates their group 27 batteries are rated to give up 1 amp continuously for 100 hours to an unhealthy discharge voltage of 10.5.

That's 4.6 days. I know that real world performance is often different from printed guidelines, but my goal is 12 hours.