newbie needs help with my Napoleon NZ3000 ZC fireplace!

[ScotO]

installing my NZ3000 fireplace this weekend, and I need to know if anyone out there can help me with the hot air ducting (not the flue, but the ducts that pipe hot air to my central air system).....what kind of temps do these pipes reach when a blower is used to take the air from the stove, do I need any specific clearance from combustibles on these pipes? I love this fireplace, it looks fantastic and is well built, but the instruction manual they give you with it, well, quite frankly, SUCKS......I think you have to buy their heat duct kit (which is another thousand dollars for some galvanized pipe and a blower) to get any specific instructions....my plan was to run these two heat ducts under the hearth and into the basement where they would be attached to a square duct with a filter and inline blower, then piped over to my central air system to be distributed throughout the house.....I need to find out if I can put them in that confined space under the hearth now so I can get this darned thing installed before the frost starts setting in!! Any help would be appreciated, and by the way, thanks guys for the great site I can see my wife going nuts with me being on here all the time....if it's not facebook its Hearth.com!!

 

[Don2222]

Hello

My 6" heat ducts for my wood pellet stove upstairs in the kitchen and living room put out 150 Degrees F with the stove on Medium so I would say not more than 200 - 250 Degrees.

I use 6" ductwork used for regular HVAC systems that works fine because their air temps are typically around 225 degrees.

Check the heat output of you wood stove with one of those inexpensive infrared heat guns to be sure.
Also be careful of the fire codes although there is no specific code for ducting wood or pellet stove heat!

Good Luck

See pic below

 

[ScotO]

Hello

My 6" heat ducts for my wood pellet stove upstairs in the kitchen and living room put out 150 Degrees F with the stove on Medium so I would say not more than 200 - 250 Degrees.

I use 6" ductwork used for regular HVAC systems that works fine because their air temps are typically around 225 degrees.

Check the heat output of you wood stove with one of those inexpensive infrared heat guns to be sure.
Also be careful of the fire codes although there is no specific code for ducting wood or pellet stove heat!

Good Luck

See pic below

Don2222, Thanks for replying.....well just to be overly sure, I went ahead (in the cavities that I am installing the pipe in under the heart) and lined those cavities with Hardibacker cement board......all the way around....and am installing the 6" metal ductwork in those channels and leaving a one inch airspace around the pipe...more than enough for firecode....I'll post pics when I get a chance of how I did it......and then hopefully get some feedback.....I had to go under the hearth to get into the fireplace from my chase, as I want to install a filterbox and a blower dedicated to this fireplace only.....put it on a thermostat and it will be piped into my hot air ductwork in the basement to be distributed throughout the downstairs floor of our house...Napoleon wants almost a thousand dollars for the same thing that I built for under 200 bucks....and my system should work better.....we'll see....thanks for the advise, I will most definately be investing in one of those infra red thermometers...

 

[begreen]

Actually there is specific code for ducting stove or pellet heat. It is not permitted to have a return air duct from a heating or ventilation system within 10 ft of the appliance. But that does not apply here. This is covered by mechanical code and the testing of the appliance. Normal furnace supply air plenum temperature is about 130-150F, with about 120F air coming out of the register. 200-250F would trigger high limit switches on a hot air furnace plenum. Usually these are set to about 170F.

I can appreciate your wanting to save money, but be sure not to guess at this. According to the directions this system relies on a backdraft damper from preventing the ductwork off the fireplace from receiving heat unless the blower is running. The ducting between the fireplace and blower need at least 1" clearance from combustibles and should be metal only.

The NZ62CH manual is posted here. Please read and don't cut corners.

(broken link removed to http://www.stovesdirect.com/product-sku-NZ62CH.html)

 

[ScotO]

Actually there is specific code for ducting stove or pellet heat. It is not permitted to have a return air duct from a heating or ventilation system within 10 ft of the appliance. But that does not apply here. This is covered by mechanical code and the testing of the appliance. Normal furnace supply air plenum temperature is about 130-150F, with about 120F air coming out of the register. 200-250F would trigger high limit switches on a hot air furnace plenum. Usually these are set to about 170F.

I can appreciate your wanting to save money, but be sure not to guess at this. According to the directions this system relies on a backdraft damper from preventing the ductwork off the fireplace from receiving heat unless the blower is running. The ducting between the fireplace and blower need at least 1" clearance from combustibles and should be metal only.

The NZ62CH manual is posted here. Please read and don't cut corners.

(broken link removed to http://www.stovesdirect.com/product-sku-NZ62CH.html)

BeGreen, I downloaded this NZ62CH manual almost two weeks ago and everything I have done so far has been within specs of this manual......all my ducts are galvanized and within the one inch clearance, but I also lined the closed cavities that they are running in with Hardiebacker cement board for extra protection, just to be safe....I will post some pics on here for your opinions when I get it finished this weekend...and I also am definately using backdraft dampers, just like the manual suggests....I am just NOT going to spend a thousand dollars for the same stuff I can put together for a fraction of that price....thanks for all the great info and for the great forum!

 

[begreen]

Sounds like you are taking the right precautions and not cutting corners. That really is the bottom line, keep it safe. If you want better piece of mind you could wire a high limit switch in the intake duct that cuts off the blower. What did you choose for an inline fan?

 

[ScotO]

Sounds like you are taking the right precautions and not cutting corners. That really is the bottom line, keep it safe. If you want better piece of mind you could wire a high limit switch in the intake duct that cuts off the blower. What did you choose for an inline fan?

I am actually going to have a filter box/blower motor combo fabricated that the ducts will run into....both ducts will come into one square box, where the heated air will go through a filter and then be piped into my hot air ducts on the bottom floor of the house...I want to look into a anti-backdraft damper for my main trunk line coming OUT of my gas furnace as well, so I am not pushing my fireplace air down into the furnace and "backwashing" dust out of the furnace filter box......I think the system will work good, getting my heat ducts under the hearth with the proper clearances was the challenge and I think I got that covered....I would still like to install some insulation around that hot air pipe inside the runways where it goes under the hearth, wonder if UNFACED fiberglass insulation would be OK for that purpose, or should I look into the ceramic insulation? where can I find that ceramic insulation?