Harman Accentra OAK?

[pfmaloney]

After a long search. I finally decided on a Harman Accentra Insert to supplement my propane furnace. Many thanks to those on this forum for the wealth of information supplied here. I originally wanted to get the Enviro M55, but decided not to when I learned that it can't be installed into a prefab fireplace. The prefab would need to be removed and new enclosure built.

From what I have read, it seems to be a good idea to have fresh air supplied to the insert. Since my prefab had an OAK installed, can that be leveraged in any way for the new insert? On the outside wall, there's a circular vent for the air.
When I asked my installer about this, he said 99% of the time, the OAK is not necessary. What do you guys think? Next week, they are coming for the site inspection so I wanted to be prepared on this subject.

Thanks, again.

 

[Trickyrick]

After a long search. I finally decided on a Harman Accentra Insert to supplement my propane furnace. Many thanks to those on this forum for the wealth of information supplied here. I originally wanted to get the Enviro M55, but decided not to when I learned that it can't be installed into a prefab fireplace. The prefab would need to be removed and new enclosure built.

From what I have read, it seems to be a good idea to have fresh air supplied to the insert. Since my prefab had an OAK installed, can that be leveraged in any way for the new insert? On the outside wall, there's a circular vent for the air.
When I asked my installer about this, he said 99% of the time, the OAK is not necessary. What do you guys think? Next week, they are coming for the site inspection so I wanted to be prepared on this subject.

Thanks, again.

Get the OAK. If you do not that combustion blower will pull the, not insignificant, volume of combustion air from the inside of your warm home and suck it to the outside. Now if you do that, you MUST suck in new air from the ouside. This new air will need to be warmed up to your inside air temp. Granted this will come from your doors and your window leaks but if your combustion blower needs to move say 800 cubic feet per hour (10X10X8 foot room) why would you force the heating system to warm that air from Outside temp to your house temp when you have perfectly good air outside that you can use and NOT have to heat.

While these OAKs are NOT needed, I can not imagine sucking in cold air into livingspace (creating artificial drafts) only to heat it when I'm trying everything to keep the natural drafts out to save on heating costs.

 

[pfmaloney]

Can the air vent on the exterior wall that was used by the prefab fireplace be utilized with the insert's OAK?

 

[Trickyrick]

Can the air vent on the exterior wall that was used by the prefab fireplace be utilized with the insert's OAK?

Yes and no. If you look at the instal instructions there is a section that needs to be installed to the frame rail system that is mounted to your fireplace floor and a connection that must be mounted to the stove. This is the connection to all venting and allows you to yank out the stove for cleaning. You need that part to attach to the framework. From that point you can use the existing hose and vent but you must have that portion of the kit. This is not really something you can make and if you connect the stove directly to the pipe, every time you pull the stove out to clean you will disconect to stretch this hose.

 

[pfmaloney]

That's exactly the information I was looking forward to. Thank you. I have one more question. I do not have a raised hearth. Does this affect the slide out feature of the Accentra?

 

[Trickyrick]

That's exactly the information I was looking forward to. Thank you. I have one more question. I do not have a raised hearth. Does this affect the slide out feature of the Accentra?

Hmmmm how to answer that..

The base that you mount the unit on to must be at the same elevation. That is inside the fireplace (I know you do not have a brick fireplace) but if you did the inside and the top of the hearth must be at the same level. This allows the stove to sit level. Now for the hearth height to the floor. I think by code you need 1 inch higher right???? Well that depends on you code I guess doesn't it.

As for pulling the unit out (the floor and top of hearth can be at the same level) note if you have carpet that is beyond the hearth then you may have an issue depending on pile height.

Note you need to have the hearth built out past the pellet insert fire box. This sticks out of the wall quite a bit so it you need 12 inches and the fire box is also 12 inches out then your hearth needs to be at least 24 inches from the opening. Just something to consider.

Go to the Harmon site and download the Manual and it will tell you exactly what you need

Note if you are using their zero clearance box that has a 1 inch thick bottom to it that will raise your stove up 1 inch above the subfloor.

 

[pfmaloney]

The inside will be at the same level as the hearth. According to the Accentra manual, I just need six inches of hearth from the front of the unit. The top of the hearth is an inch above the carpet.

 

[Trickyrick]

The inside will be at the same level as the hearth. According to the Accentra manual, I just need six inches of hearth from the front of the unit. The top of the hearth is an inch above the carpet.

You need 6" past the front and I think either side right so Minimum hearth is 18" from the wall and 40" wide. If you have that then you meet the minimum...

Are you using the zero clearance box from Harmon. If so then that is 1: tick at the bottom and will screw up your measurements. If I were you I would build my own fire "proof box" but remember you have the 2 vents coming out of the stove. You can either have them coming out horizontal or vertical but without the ctove frame you can't reliably place your holes through the box.

You really have to moun(dry fit) everything first then mark from there.

I used the Harmon box and I picked that up a week before the stove so I could build to that. Harmon couldn't give me reliable measurements to prebuild to.

Rick

 

[wilburg]

ok, you guys have me 100% confused. I am expecting to get the insert accentra in a couple weeks. The OAK ... I am sure the installer understands what that is if I ask for one, and it sounds like you guys convinced me to get one. About how much should I expect to pay for this OAK thingy.... Also I have an uneven field stone fireplace with about an 18" bottom (hearth?), should I get the rail system and how much should I expect for that. Is there anything else I should buy with this thing?

 

[Trickyrick]

ok, you guys have me 100% confused. I am expecting to get the insert accentra in a couple weeks. The OAK ... I am sure the installer understands what that is if I ask for one, and it sounds like you guys convinced me to get one. About how much should I expect to pay for this OAK thingy.... Also I have an uneven field stone fireplace with about an 18" bottom (hearth?), should I get the rail system and how much should I expect for that. Is there anything else I should buy with this thing?

I think the whole OAK was something around 175 or 200. Very expensive for what it is bu there isn't anything you can use other than their kit.

If your hearth is more than about an inch above the floor then you should either buy the cleaning rails or make your own. I personally would make my own but I have the tools and the wood to do it.

When you clean out the fines trap, exhaust motor/blower and perhaps accesing the auger motor then you need to yank the unit out about 24 inches from its normal run position. The question is what will you set it on. My hearth is 1 inch above my hardwood floor so it is a non isue for me, if it was 2 inches then I would set (2) 2X4s down for it to sit on above my floor. If it was 4 Inches then (2) 4X4s work.... More than that and I nail some 2X6s or 2X8 and rip to the exact height.... See where I'm going with this... You can make a system for yourself and you shoudl have this system ready prior to your install so you can set it on this while you run the wires or the make any last minute adjustments...

Rick

 

[wilburg]

ty!

 

[Trickyrick]

As to the question of what else you need to run your stove?

Tools.

You need:

A flex brush that is made for the diameter of the exhaust vent. (I got one ov those drier vent cleanout brushes) No read creasote so nothing super hard to knock off.

An old 3 inch painters brush to "sweap out" a clean stove.

A crappy old "BAG" type vacuum. (Think yard sale here guys) Do not use the house canister or bagless unit and DO NOT USE your wet/dry vac without a special filter. As I use my wet dry system for woodworking I do not contaminate it with ash. You need a bag vacume to catch the fine crap...........

An old (I think it was once a #2) flat head screw driver. Take it out to a grinder and grind off 1/8 inch of the tip flat (perpendicular to the handle. This gives you 4 nice sharp edges to scrape with and quench this in water as you grind (You want it hard) You can bend it 10 -15 degrees if you have a hot enough torch but not necessary. This is your every day scraper.

A good surge supressor. Remember ther is a computer inside this thing. OK a circuit board anyway. You so not want it fried cause skippy the neighbor has a garage band.

I can not recommend hardwiring this thing, I ran my power down to the basement, If you have a cleanout trap in the fireplace or if you have the ability to get that cable in the basement then wire a plug in the basement that you can access and plug in there so that no wires are seen.

Start grabbing 2 bag of any brand pellet you want to try and be ready for some serious differences in Ash, burn time, and heat value. For those of us with inserts you will find that ask volume is the issue..... That pan holds about 1 week of ash when burning in the winter... If I dump crappy pellets then it fills up faster and I'm doing my cold cleaning more frequently.

I recomend to be fair on the testing of your pellts a full front end cleaning betweeen different bags. See bellow...

OH I can not stress this enough. Fly ash robs you of heating performance. 1/8 thick coating of ash on the heat exchanger (About 1 weeks worth depending on the pellets you use) seems to drop my stove efficiency by about 25%. So I clean out Sat AM and by friday night the stove still putting out the same heat but seems to use more pellets per hour when run on room temp.

If your going to ask what I burn Okies (great heat low ash) 165 degrees if I can get them between 250 and 265 per ton. They are not availablle this year sooo

1 ton Lignetics (Fair heat and low ash) 150 degrees
1 ton Hardwood heats (Good heat little more ash that can sometimes clump at low burn temps) 155 degrees

There are brands I will not touch but there are differences in everything and they may work fine for you.

 

[wilburg]

Wow, thankyou for your time. Lots of good stuff there!

 

[LIpelletpig]

Here is the link to my install for the OAK. I later removed the OAK because it made the stove run poorly. Not sure why? But I disconnected the Accentra Kit and kept the 3" hose for the OAK and the top of the chimney stayed the same. The 3" pipe goes up about 4' above the fireplace shelf.


https://www.hearth.com/econtent/index.php/forums/viewthread/41401/