Looking at getting a Fahrenheit Furnace for next winter.. thoughts?

Aside from my opinions on the furnace, I would say your on the right track as far as venting goes. Either line your chimney if it can be done so in accordance with the manufacturers specs or just vent it thru the wall. Dont just pipe it into the oil flue. Good job kicking the oil habit.

I don't know much about the Fahrenheit Technologies furnace but went to their website and it sounds great, especially if it will plug into your existing ductwork. My only hesitation would be the lack of conveniet loading if it's located out of the way.

The Fahrenheit Furnace is an excellent product, definitely state-of-the-art, couldn't be happier with mine. I had it installed new about 5 months ago, late December 2010. It cranks out a ton of heat and is very efficient to boot. I took photos of the initial installation as well as the duct work (I went with direct ducting as tying into my existing duct work would have been far more expensive, plus a 600/800cfm blower is not sufficient to crank air through a HVAC system designed for a 2500 sq. ft. house). The furnace heats my entire 2-story, 2500 sq. ft. house with ease.

Here's the thread I posted awhile back after I first had the Fahrenheit unit installed...

https://www.hearth.com/econtent/index.php/forums/viewthread/67125/

$1200?? I'm assuming the unit is used, because the Fahrenheit units retail around $3500-$4000 new. Even for a used working unit, $1200 is a great deal. Another guy who frequents this forum named "DexterDay" picked up a used Fahrenheit, so he also has one and could provide some constructive feedback as well.

I do not have it totally tied into the duct-work yet. But... Check your local code before taking the "Oil Burner" out. Ohio states that you cannot have a solid fuel force as your Primary heat. Just means there has to be another "Main" heat source in case you sell the house, and the new owners are not as SMART as you for wanting to save money.

As far as the efficiency and heat that comes from the Fahrenheit, it is amazing. After talking with the dealer and doing more research. The Fahrenheit is "Rated" at 50,000 BTU's.... But can put out close to 80,000-90,000 BTU's.. To say that it can only eat 6-7 lbs of pellets on level 5 is an understatement... Keep it clean. The parts and area's you have to clean, already having a pellet stove, you know where these are. The Endurance has clean out plates for the exhaust and combustion blower. Cleaning becomes a snap.

It auto-cleans the burn pot on its own. Can burn a multitude of different fuels and if you can get it for $1200..... BUY IT NOW!! I am with ChrisWNY on it being used. But if its new. DEF BUY ITI got mine for $2,000 with all flue and duct-work and back-draft dampers.. (oh yeah, Do not forget back-draft dampers) And I thought I got a smoking deal... So me and Chris are JEALOUS, to say the least

Read the manual and you will be fine... Actually... Make sure you read it a few times. It never hurts to know to much. Also, try and keep your existing furnace (depends on code) Always nice to have a back-up. Never know when a blower or something will fail on the Fahrenheit. I know you still have the Englander (I still have the Quadrafire). But Pellet stoves are not as reliable as a Standard Furnace. You Found a heck of a deal whether its new or used. Congrats.

There are 2 other Bio-Mass Furnaces that I was looking at. The Harman PF-100 and The St. Criox Revolution <(Beauty of a furnace)

If money was not an issue. I would buy the St. Criox. The "Clinker Cutter" system is probably the best self cleaning system out there. The Fahrenheit has a good cleaning system also. But there are flaws to it. Make sure the dealer has the upgraded control board and burn pot. The burn pot should be 2 piece's. Split down the middle. Its a sloppy system. But it works. I have no regrets buying mine. But had I gotten a oppurtunity to buy a Revolution. I would have.

Follow the manual. Make sure you use 4" pipe (multi fuel). Simpson Duravent Pellet Vent Pro is a good flue pipe. Also make sure to hook up an OAK. Congrats on the find. Good luck and keep is updated.

You want to minimize horizontal runs in your 4" pipe, as well as minimizing the total length of the pipe overall. PL venting is expensive; keep in mind that elbows, Tee's, and horizontal piping add resistance to your exhaust setup, there are formulas out there (for example, an elbow is equivalent to 5' of vent pipe in terms of resistance). Your furnace should go where the PL vent is minimal length to go up and out of your house, don't worry about having to run extra ducting, ducting is MUCH cheaper than PL vent. You will need dampers to tie into your existing duct work. You may want to consider cutting a couple vents into your floor and direct ducting your furnace, it's the least expensive option IMO.

Yes you must run dampers when using existing HVAC.

ChrisWNY suggested its own ductwork. You said you didn't have basement. But you could buy the diffuser for the furnace and the blower on the Fahrenheit has enough airflow to create a lot of air movement. If your house is under 2,000 sq ft and your floor plan is open. You may not need the ductwork. I got away with a freestanding Quadrafire for 3 yrs. Much smaller blower on it than the Fahrenheit.

Horizontal runs must have a 1/4" rise per foot. And like Chris said. Keep it and all other elbows to a Minimum. The best advice I can give you, is to use either 2 Cleanout T's or a 4 way Cleanout from the vertical section coming off the furnace going to the horizontal out the wall. Keep is updated.

Any possible way to keep the existing furnace intact? Better to have a back up just in case.

For $1200 I'd be all over that puppy and fast! Nice deal for ya!

That's what a back-draft damper does. You need one for the Fahrenheit, to stop air from the furnace/central air, going back into Fahrenheit outlet. And one for the furnace, to stop air from the Fahrenheit, going back into your Furnace. They are just a simple damper. The dampers I have, are like a butterfly valve. When either unit kicks in, it opens the damper on the top of it (naturally opens because of air pressure) and the incoming air in the system closes and applies pressure to the other damper. So only one unit can be ran, and it runs efficiently, by not letting any heated air escape through the other unit. Sounds much more complicated than What it is. I will try and get a pic of one when I get home this evening.

Yes they do. You can buy them or of you know someone who does HVAC, they can make you one. But they do sell them, in all shapes and sizes.