waste oil boilers

[Jens]

At the risk of being tarred, feathered and run out of town, I thought I would bring up the issue of boilers.
As some of you may know, I ran a Listeroid 20/2 for roughly two years for heat generation. Originally the plan was to generate electricity and feed it to the grid but the cost of the grid connect system as well as the permits etc made this a non-starter. This is when I ended up using the Listeroid to generate electricity to heat water and captured as much waste heat as I could in order to heat my house as well as pre-heat the domestic hot water.
The engine required a lot of attention and it occurred to me that since all I was using it for is to generate heat, why not stop fiddling with all that moving 'stuff' and just heat water directly with a waste oil heater.
My question is rather straight forward: Have any of you had experience with waste oil boilers? Specifically, the commercial kind that can be installed in a residence without the insurance company throwing a giant snit-fit. Something that can be inspected, certified, permitted, stamped, signed and whatever else the 'authorities' want to do with it. I am looking for something below 100k BTU with the idea being that I would heat a large amount of stored water and use that stored hot water to heat my house hydronically.
I am looking for reliability, very little maintenance and unattended operation.

My hydro rates are going to jump 25% next year and possibly another 25% in a couple of years after that so I am looking for alternatives.

As we rarely have a power outage, I would replace my Listeroid with a self contained diesel genset strictly for generating electricity just in case but would expect this set to only run 6 hrs per year for system testing. The boiler would run a couple thousand hours per year and might be augmented with solar heat collectors for summer operation when no space heating is needed but we still need domestic hot water.

Thoughts ?

[billswan]

Jens

Well join the party, I did the same as you are thinking of doing.

Have used a clean burn brand of boiler fueled with waste engine and hydraulic oil for 2 full seasons.

It was the smallest unit they sell at 200000 btu's.

That nasty crud that comes out of burning used oil does fill the burn chamber up. Thoughts of the famous poster spencer and his ash come to mind.
The company claims 750 hours between burn chamber clean outs. Well that might be a stretch, more like 400 hrs. With my experience.

You will have a problem finding a boiler in you size range, not to sure I ever saw one that small.

Price will be a problem too as mine cost $8000 before install.

Hate to quite here but soybean harvest started yesterday and my combine needs me.

Billswan  ps were you still going to use veg oil??  I Have zero experience with it................

[Ronmar]

That might be your biggest hitch, I have not seen a small one.  Probably because of the marketplace.  In many cases, this is a corporate thing targeted at companies who generate enough waste oil to support such a process.  I know here in the US, collecting oil can be problematic, as businesses that deal with waste oil must track it's disposition to a liscensced disposition facility.  And I think those who use it in their own boiler must be EPA liscensed and the boiler EPA certified.  Not sure what the rules in Canada are, but would not be surprised if there is something similar in place, so that leaves you with some business letting you have it off the books, or friends neighbors relatives who do their own oil changes.  With the rules here, there just is no real market for small certified units.  Probably why you see so many small scale home brew babbington type burners on Youtube:)

That is why I am working on my own multi fuel water heater(stick wood, chips, pellets and waste oil).  But it will NOT be installed in my home.  It will be something I wheel out of the garage, connect to quick connects into the water storage system, and light it off for a batch run when my planned solar isn't up to the task... 

[Jens]

Thanks guys!
I had not considered fuel yet but thought that both WVO or WMO could be potential candidates. Preference obviously would go to WVO.
I am disappointed to hear that no small units are available .... in the back of my mind I was hoping that there was something available like the burner in my boat (also used for highway trucks to heat the cab and pre-heat the engine). It's the size of a shoe box (literally). The unit I have is diesel fueled and isn't meant to be taken apart for regular cleaning but the concept of a small unit running long hours sounded good to me. No super heat output would be required since the heat was stored in a water tank. Of course I didn't realize the 400 hr cleanout interval which could be problematic if the unit runs 10 to 15 hrs a day. The units I have seen on the internet (larger heat output) claim up to 2000 hrs between cleanings but they don't specify fuel used to get those hours (I suspect diesel and not waste oil). They also specify 30 minutes for cleanout.
I will do more internet digging but things aren't looking too promising.
Oh, 8k doesn't scare me too much ... what scares me more is the hydro bills that keep coming and are getting bigger and bigger. I figure $2k for a year at the moment which isn't too bad but wouldn't be surprised at $3k in a couple of years in which case the heater would pay it's way in short order. 

[mobile_bob]

a former business partner of mine, who is also a member here, although i am not sure if he comes on much has a vast knowledge and experience with waste oil furnaces and boilers.  he heated his auto repair shop for years using waste motor oil and his 6k sq/ft home with a waste oil boiler... both worked very well and if i recall correctly the maintenance was not that bad.

i seem to remember a unit he told me about that was in the 90kbtu range, that was around 4-5grand?

i don't recall him having to clean the boiler but maybe once each heating season.

bob g

[Jens]

i seem to remember a unit he told me about that was in the 90kbtu range, that was around 4-5grand?
i don't recall him having to clean the boiler but maybe once each heating season.

That sounds exactly like what I am looking for, Bob!
You wouldn't by any chance have a brand name? Alternatively, if you could pass on his member name I could email/message him privately.

[mobile_bob]

Jens

iirc the manufacture of his boiler is "omni" and the space heater was "lenaire" (sp)

i don't recall Marks member name, it might be "mark" or some derivative?

its been quite some time since we last talked, i think i have his phone number here somewhere, however
that is not certain as i washed my wallet a while back and every piece of paper got turned to lint, including the business cards with his number on it.

i might still have it on my old cellphone, i will try and find it, charge it and see if i can retrieve it.

failing that, i do think it was "omni" that made his boiler  and last i knew he loved the darn thing.

bob g

[Jens]

Thanks Bob, I will look for Omni - it sounds vaguely familiar as if I had seen it on the internet before.
I have a habit of washing my wallet (and on at least one occasion my cell phone) as well. Money is very dirty so a good wash is a good thing

[glort]

Why the small output Burner?
If you are heating an amount of stored water, you can heat it at a higher rate for less burn time on the boiler and then circulate it for the heat as you would anyway.

The rating of burners can be changed. They use a Nozzle to atomise the oil and by swapping that out to the output you want and adjusting the air on the burner gun, you can easily de-rate the things .

I have built quite a few waste oil burners that I'll one day use for heating my pool. The idea there was to do much as you are thinking and heat the water then just circulate it for heating the house.  I might get away with 1-2 burns a week.
For that Volume of water I prefer higher heat outputs, like Millions of BTU output but I have made some smaller burners as well.

One I used last winter I put under a gas fired water heater that I took the gas burner from.  I could boil the 100L of water in under an hour with that so it provided more than enough heat for the house. I just used a solar circulating pump on the thing and it was no trouble.  The burners I build are self cleaning. I could run them forever and never have to clean them.  I mainly use WVO and WMO but have used tranny fluid and some Hydraulic oil as well.  All burns the same except veg has a slightly lower heat output.

I did the same as Ronmar and had the thing outside my home and well away.  I sat the whole thing in a deep tray of water so if there was a problem there wouldn't be one for long and had it set up so any problems would cut the power. I just ran it when I was around the house and switched the Burner off at night.

This is a Vid of the latest Burner I made:

[Jens]

Smaller BTU means smaller physical size. I don't actually know how many BTU's I use in an average day but believe 100k will be enough for the coldest winter day. A lot of the heating is needed for shoulder season where I should be able to get away with half the BTU's or less. I also have the electrical heating system as a backup if needed.

[Ronmar]

100K BTU/HR ?  That is a lot.  I live in a very poorly insulated home a little bit south of you and I manage mostly on a pellet stove running on low a tabout 12-13KBTU/HR based on pellet burn and stove advertised efficiency.  That is a little less than my 6/1 outputs thru the cooling system at full load.  I have a little bit of electric supplemental heat running when it gets really cold, but at the worst it gets here in Port Angeles, not over 20KBTU/hr I think...

Looking at the Omni website, the Omni-9 burns about 78KBTU/HR in fuel(.6 gal/hr). With it's efficient tripple pass boiler design puts about 66K of those BTUs/hr into the water. That would be 3 times my needs, but would probably work pretty well as a batch heater to charge a storage tank every couple of days when there is no available solar.  My new house will be super insulated with hydronic floor, so I forsee a lot less than 20K/HR heat load on the worst days.  It looks pretty small, so would probably work OK on a cart.  I wonder what the pricetag is:) 

[Jens]

Yes, I was looking at that boiler.

The reference I have to actual BTU needed is the fact that I ran my 20/2 at about 95% for I think close to 6 hrs/day (it's been a while so I might be off on that). Half of that was in the morning and half at night. This gave me all the house heat I needed plus a bit of pre-heat on the domestic hot water. If anyone can translate that to a good guess of BTU's that would clarify things a lot.
The electricity generated by the 20/2 was fed to heaters in the hot water holding tanks, the coolant was fed to the holding tanks and some of the exhaust heat was fed to the holding tanks.

I did come across another rather interesting boiler http://www.kroll-heaters.com.au/kk30-wood-oil-boiler-30kw/ - it has two burn chambers, one for wood and when that dropped below a certain temperature a waste oil heater would kick in. It is rated at 30k BTU's.  Because of the wood burner section it was fairly large and most likely in the 10k or up price range. I seem to think about 650 kg so pretty massive and likely with a matching price tag.

[Ronmar]

On your 20/2 what was your fuel burn per hour at that loading?  Electrical load about 9KW?  Answer these and I can take a guess...

[Jens]

9 kw sounds about right but I never measured fuel consumption.

[Ronmar]

Well if the roid is true to form, lets say 1/8 gallon/KW/HR or 1.125 gallons in an hour feeding 9KW.  Applying the rule of thirds, If you use all the cooling system heat, that is about 52,000 BTU/HR.  That 9KW equates to around another 30,000 BTU.  82,000 BTU/HR total for engine and electric, times 6 hours = 492,000 BTU give or take.  Now take that number and divide it by 24 and you average about 20,500 BTU/HR.  I did not add in any exhaust heat recovery because I have no clue what your efficiency could be which would have a big effect on BTU collected.