short horizontal install

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Matt B

New Member
Feb 23, 2021
22
Tucson, AZ
mattbruner.com
I am still very new to all of this, and this is my first inquiry about installing the Avalon 900PS I just bought today. I still need to learn how it works and bench test it, though I am working on that. Looking ahead to the install.

I can install the vent vertically, but all I have is a hole in the roof, basically, so I would need to buy all the rest. I am looking at the instructions (that are about 20 years old.) It shows a horizontal vent install with 3-inch clearance on the back, three inch pipe through a thimble, and 1 foot extension beyond the exterior wall. Elsewhere, it mentions 4-inch pipe for high elevation.

Question one - does the 1 foot extension beyond the wall still make sense? (changes in code, conventions, etc.)
Question two - does it make any sense to use 4-inch pipe when the whole run will be about two feet? (I am at 8000 feet elevation.)
Question three - the diagram shows a termination with a 45-degree end, which would be about one foot above the interior floor, but obviously outside. Does this assume that the exterior wall would be well above a horizontal surface. In my case, there would be two feet of pipe, the 45 degree downturn, with the discharge one foot above a wood deck. The instructions don't say "no." But that seems weird to me. How hot is the exhaust and does it spit any sparks? It this just a plain old "that is bad."
 
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4" venting when the total run exceeds 10 feet. So it's used and probably run hard and not maintained very well. Time to take all the powered stuff off (convection fan, combustion fan, auger drives) and clean them and oil the bearings and grease the reduction gearboxes. Check and clean the burnpot (soak in water for an hour to remove the carbon), check all the wiring for bad spots in the insulation and makes sure all the terminals are tight, then get into the control board. Finally use a surge supressor on the line cord and check for cracks in the firebox too. It's an old girl.

1 foot above a wood deck don't work. btw.

Go with the vertical install. 3 out of the stove to a 3-4 cleanout Tee and 4 up to the vent cap. Use the longest lengths of venting you can buy. I suggest Venting Pipe .com they have pellet vent (Simpson and Selkirk) in 5 foot lengths and they don't interchange either, You go all Selkirk or all Simpson but you cannot mix.

Make sure it works properly before jumping into vent pipe.
 
If you ever get sparks from the exhaust, your combustion air is way too high....
 
If you ever get sparks from the exhaust, your combustion air is way too high....
So the answer is "it shouldn't, but it could." Enough on that!

You confirmed my suspicions on the venting plan. Up it will go, unless someone really makes a good argument otherwise. Good tip on the brand incompatibility - I did not know that!

I want to see if the stove works, then I will go through it. I went over my wife's 1966 pickup, and it turned out very dependable - cleaned all of the connections, lubed the moving stuff, replaced the sketchy things, made notes, got an understanding...

For surge suppression, I plan to get an APC uninterruptible power supply. Not that I need the backup, but they are great surge suppressors. I buy them at thrift stores, usually under $20. I have them on the computers, stereo, TV, studio equipment... I don't think we have had an electronic failure in 15 years.

Thanks for the guidance!
 
You never know Matt B. and it is good to have things like that--just in case---you don't want to have to replace it because the wiring burned up and good luck with your endeavor hope it works out real well. chancey
 
I buy them at thrift stores, usually under $20. I have them on the computers, stereo, TV, studio equipment... I don't think we have had an electronic failure in 15 years.
Not even close to enough ooomph for a pellet stove. You have at least 175 watts input @110 volts. It's not an electronic piece of equipment other than the control board. Everything else is electro-mechanical.
 
Not even close to enough ooomph for a pellet stove. You have at least 175 watts input @110 volts. It's not an electronic piece of equipment other than the control board. Everything else is electro-mechanical.
We may be talking about different things. I think these are rated for 300 watts. I will research before I commit.

Thanks!
 
Used UPS such as the APC backup or surge suppressor, is a gamble when you buy used, how many power surges have gone through it & can it still protect electronics,..also usually the battery goes bad on them and it makes more sense to replace the whole unit than a battery..
 
If it wasn't a wood deck I would say run it out the wall. Shorter exhaust is better for cleaning and cost. Mine is 24" straight out of the wall on to a open porch. When I get a strong North wind I stick a 90 pointing down, besides that it is just have to clean the concrete porch after every winter where it has dumped black soot everywhere. The exhaust is not very hot and if it running correctly there should be no sparks.
 
So I cleaned up the Avalon today - made a cloud of ash with my compressor. I checked the connections and test ran it in the back of my pickup truck. It is an older model that has no automatic ignition. I got the fire going with a propane torch like the previous owner suggested, and it made a nice flame.

I decided on the vertical vent, based on the advice here. I had everything I needed already from the seller for the horizontal vent, but it just didn't make sense to not follow your good advice. I checked prices for the parts at a couple of online shops and on Amazon. Cost for ten feet of 4-inch pipe and all of the adapters and such was just at $700. On a whim, I checked Home Depot. They had everything I needed, and it was $300 cheaper!

The cabin has a 3-inch pipe that starts at ceiling level and goes up a couple of feet. I will take that out and put in the 4-inch. There is a hole in the paneling, but not the exterior wall for a OAK kit. I will likely do that as well, despite the cabin being pretty leaky.
 
My old girl is a manual start as well. Actually, I prefer it over cal rod ignition. one less part to fail.

I have a jar of wood pellets I soak with charcoal starter fluid. Dump a handful in the pot, light with a match, close the door and punch the on button and in 3 minutes it's good to go. Every time. Running on corn, I have to start it on pellets. Corn is difficult to start alone.
 
My old girl is a manual start as well. Actually, I prefer it over cal rod ignition. one less part to fail.

I have a jar of wood pellets I soak with charcoal starter fluid. Dump a handful in the pot, light with a match, close the door and punch the on button and in 3 minutes it's good to go. Every time. Running on corn, I have to start it on pellets. Corn is difficult to start alone.


Great idea. I have taken note!
 
Be sure to read the owners manual and plenty of room surrounding the stove for service. Post update when up and running, & you may have more questions...
 
Be sure to read the owners manual and plenty of room surrounding the stove for service. Post update when up and running, & you may have more questions...
There WILL be questions, amigo. This process went from "we need more winter heat" to "I own a pellet stove" in two weeks. I have been a southerner and flatlander all my life, so the whole concept is new. It just happened that we live in the southern desert (it was 82 a couple of days ago), but have a cabin on a tall, nearby mountain.

Our chosen stove spot will protrude into the room a bit (small cabin), but we will have nice access to the sides for maintenance and repairs. Good point though, the pellet stove is not like a space heater. You don't unplug it and throw it out if it misbehaves! Access is important!

We are at the tail of the cold season, so I might not get to give it a good workout until fall. Depends on how fast I install it! I plan to move it into place on friday, and the vent parts will be here in a bout 7-10 days.