OAK for my Harman P68... Finally!

[stayfitz]

Well... After two seasons of use with my Harman P68 I decided to acquire materials and prepare for OAK installation. Better late than never! Looking forward to the potential change in household pressure...

 

[Brew]

Looking forward to hearing how you like it, before-and-after. One person elsewhere on the forum reported no longer feeling cold air rolling across the floor toward the stove after an OAK install. Smart move!

 

[stayfitz]

Hopefully I can provide some objective feedback... ;-) Stay tuned

 

[stayfitz]

OAK installed. I wonder if the bend is necessary? I thought it might be useful for moisture back-flow prevention? I certainly can change and straighten, if there is too much resistance/drag. The entire 2" hose section is approximately 24" long.

 

[heat seeker]

Maybe the bend will "turbulate" the air and give you a better burn...

 

[Heat Slinger]

Subscribing...curious to see how it affects your pellet consumption this season.

 

[Oink Oink]

Can you list the parts that you used?

 

[stayfitz]

This thread/post was the inspiration - https://www.hearth.com/talk/threads/harman-oak-adapter-found-one-from-summit.112138/

Here are the specific items:

http://m.summitracing.com/parts/wlk-41999

http://m.summitracing.com/parts/wlk-41959

http://www.fleetfarm.com/detail/duravent-fresh-air-intake-kit/0000000071273

 

[ttdberg]

Thanks for sharing this, sincerely appreciate it! After 6 years, I'm thinking of installing an OAK for my P68 too. This info is extremely helpful.

 

[stayfitz]

Happy to help! The credit goes to all the incredible people associated with this forum! I'm looking forward to cooler weather and experiencing the OAK benefits

 

[stayfitz]

I'm waiting for resolution regarding a Harman warranty matter. So, I don't want to start up the stove until everything is settled

 

[ttdberg]

Stayfitz, I'm going to go with the same parts you ordered. Question for you. The Duravent 2" OAK specs indicate that it's 5 feel long when fully extended, was this your experience? When fully extended, is the pipe rigid (does it retain it's shape) or is it flimsy like dryer vent hose? From the picture you posted, it looks rigid, but just want to confirm? In my application, I will be running the OAK pipe a few feet up into my 8" fireplace flue, along side the 4" flex flue that's already there. I will need the full 5 feet of OAK pipe to do this. From what I have read, it is not necessary to go all the way to the top with the OAK, like the 4" flue does (someone please correct me if that is wrong). As part of this install, I will need to drill a few holes near the top of the 8" flue, above where it exists the chase. The 8" flue extends a full 18" above the top the the chase, so I have plenty of area to do it. Once those holes are drilled, I will cover them with screen to keep pests out, and also block off the damper area with non-combustible insulation, so no cold air can come down the flue into the house. I don't have it blocked off today because there is a sealed block off plate at the top and no chance for any cold air to come down currently.

 

[TimfromMA]

Did mine over the weekend. It will be interesting to feel the difference this winter.

https://www.hearth.com/talk/threads/added-oak.129843/

 

[stayfitz]

Stayfizt, I'm going to go with the same parts you ordered. Question for you. The Duravent 2" OAK specs indicate that it's 5 feel long when fully extended, was this your experience? When fully extended, is the pipe rigid (does it retain it's shape) or is it flimsy like dryer vent hose? From the picture you posted, it looks rigid, but just want to confirm? In my application, I will be running the OAK pipe a few feet up into my 8" fireplace flue, along side the 4" flex flue that's already there. I will need the full 5 feet of OAK pipe to do this. From what I have read, it is not necessary to go all the way to the top with the OAK, like the 4" flue does (someone please correct me if that is wrong). As part of this install, I will need to drill a few holes near the top of the 8" flue, above where it exists the chase. The 8" flue extends a full 18" above the top the the chase, so I have plenty of area to do it. Once those holes are drilled, I will cover them with screen to keep pests out, and also block off the damper area with non-combustible insulation, so no cold air can come down the flue into the house. I don't have it blocked off today because there is a sealed block off plate at the top and no chance for any cold air to come down currently.

The Duravent kit is not the highest quality. I noticed the duct/hose separating a bit at seams when extended. I think their 60" extension reference is rather optimistic. The duct/hose is fairly flexible to bend, but rigid enough not to lose it's primary 2" diameter shape. Knowing a little more about the duct/hose (from the kit), I would probably consider another product...

 

[ttdberg]

Thanks for the candid feedback, appreciate it.

 

[stayfitz]

This thread/post was the inspiration - https://www.hearth.com/talk/threads/harman-oak-adapter-found-one-from-summit.112138/

Here are the specific items:

http://m.summitracing.com/parts/wlk-41999

http://m.summitracing.com/parts/wlk-41959

http://www.fleetfarm.com/detail/duravent-fresh-air-intake-kit/0000000071273

My May 2012 P68 was replaced today by HHT and my local dealer (warranty defect issues). The new unit was manufactured March 2014. The new unit features several production changes. One of which is the outside diameter of the OAK collar. The old one was 2.75", the new one is closer to 3". As a result I purchased a replacement reducer - 3" ID to 2.5" OD. Unfortunately, the fit at the collar is slightly loose.

Here is the new part - http://m.summitracing.com/parts/wlk-41974

 

[stayfitz]

Had our first burn of the season with the OAK over the weekend... Seemed like heat output/flame height was much higher on lower feed rate settings!? Outside temps are moderate again, so might not burn for a while. Will keep everyone posted with more feedback

 

[ttdberg]

The Duravent kit is not the highest quality. I noticed the duct/hose separating a bit at seams when extended. I think their 60" extension reference is rather optimistic. The duct/hose is fairly flexible to bend, but rigid enough not to lose it's primary 2" diameter shape. Knowing a little more about the duct/hose (from the kit), I would probably consider another product...

Quick follow-up question: Besides the Duravent 3PVP-AIK kit, where else can you find 2" semi-rigid aluminum flex pipe to use for the OAK? I don't need the whole kit, only the 2" flex pipe. Have searched and other than in this kit, it just doesn't seem to exist. 3" is the smallest I can find anywhere either on-line, or in hardware stores. Any ideas? Maybe I'm looking in the wrong places or using bad search terms?

 

[taytowers]

Seemed like heat output/flame height was much higher on lower feed rate settings!?

My Castile was installed without an OAK... I will have one installed for next season... Keep us updated with your before and after experience.

 

[zrtmatos]

This thread/post was the inspiration - https://www.hearth.com/talk/threads/harman-oak-adapter-found-one-from-summit.112138/

Here are the specific items:

http://m.summitracing.com/parts/wlk-41999

http://m.summitracing.com/parts/wlk-41959

http://www.fleetfarm.com/detail/duravent-fresh-air-intake-kit/0000000071273

Are these the same parts required for a Harman P38+?

 

[ZBrooks]

I didn't need the pipe reducers. My 3" flex must have been easier to tighten down than Don's.

 

[TimfromMA]

This is my first season with OAK after 4 without. So far the biggest difference I see is in the reduction of drafts since the stove is no longer sucking in heated house air. I've noticed no significant difference in pellet consumption or heat output.