Central forced-air kits

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DiscoInferno

Minister of Fire
Hearth Supporter
When I was shopping for an EPA-certified ZC fireplace/stove, I noticed that several brands offered optional kits to hook up directly to existing forced-air ductwork. In fact, I chose the Security BIS Ultima in part because of this. The kit is basically just insulated flex duct, an inline blower, and adapters; the flex attaches via an adapter directly to the outer shell of the unit (which is to say it draws the air immediately surrounding the firebox) and the other end connects to the supply plenum (not the return). You run both the inline blower and the main house blower to distribute the heat. But I see all the recent threads about how it is both unsafe and against code to add returns near a wood stove; is there something about these kits that is fundamentally different? How can manufacturers offer unsafe and illegal options? I bought the kit, but I guess I'll limit my use to when I'm awake; if the inline blower isn't running then there isn't much of a path for smoke to travel from the fireplace to the house ductwork since the flex goes downwards.

This may all be moot (if a bit expensive), because the limited experience I've had with the Ultima (it's been too warm to burn much so far) indicates a much greater natural convection throughout the house than the closed floorplan and my previous experience with a heatilator-type fireplace would indicate.
 
A system that has been engineered designed and tested can be retrofitted into your existing duct system providing that the installation, and materials used clearly follows the manufactures
specs..

The cutting holes on the floor and people taking engineering into their own hands is what I'm trying to discourage.

All I can do is point out to them there is saftey risk involved.

None of the advocates has ever done the inspections after the incident has occured. I only do them when the woodstove is suspected and requested by my fire dept to do so.

Older homes used to have laundry chutes. Modern building codes discouraged their use for two reasons. They provide the channell for rapid spread of smoke and fire to upper levels
and they defeat all efforts on containment.

The issue here, is containment provides valuable seconds, perhaps minutes, for safe exit of a fire situation Doing things that reduce safe exit time is foolish.
As I'm typing, the NFPA and fire marshals are trying to introduce sprinkler systems into the residential codes. Why they add to supressing fire and buy valuable time for safe exit
Why are attached garages required to have fire code sheet rock? containment and separation They are suposed to be rated for one hour protection.
Did you know the reason bedrooms require doors? Yes it is a code requirement, Containment and separation. It has been proven, people are safer sleeping with their bedroom doors closed
 
I guess that makes me feel a little better; I only used the materials provided (although they don't seem to be anything special, just expensive) and followed the directions. The only hole I cut was in the floor of the external chimney chase, and that was just a single layer of plywood to begin with. Still, if a fire starts in the room with the stove it will distribute the smoke throughout the house.

Interesting your statement about sleeping with the doors closed; that suggests I should run the central blower at night. (Although closing our bedroom door cuts us off from the cold-air returns, so I'm not sure that would work anyway.) I'd be worried that I wouldn't hear the smoke detector down by the stove if it went off first. Plus I'd have to open the door to get to my daughter's room anyway.
 
If you followed my other post there are two point I want to address central hall ceiling returns is the worst possible locations. Ones they only return warmed air and two for the point they are useless when bedroom doors are enclosed. Code interpetation if the opening has a door (Louver doors excluded) the situation must be interpeted when the door is closed. There is no code that allows under the door space as proper retern route no will cooler air ever rise to a ceiling return location. The past 11 years as an inspector all bedrooms have returns. What a waste in energy returning the warmest air of the upstairs rooms with ceiling returns No wonder the far rooms do not heat correctly no wonder people are trying to add axhilliary heat sources.
What to save money and energy I would address your duct system I would duct mastic all seams increase the insulation values and re work the routing to the shortest most direct path with fewest bends I woulkd then install high low returns in the wall cavity with dampered vents. I would seal leaks all around the furnace/ exchanger and force as much produced heat to the living space

In 1997 Somke detectors were required in all bedrooms for the very reasons you mentioned so they can be heard. even over outside distractions like your TV. With the door closed and tv blaring you are right it might be hard to hear the hallway detector. IE bedroom requirements.

I have said all along there are two parts of the equasion to reducing energy usage one do a better job of keeping produced heat in and suplemental sources. Money is just as well spent adding insulation and sealing drafts adding insulation to water heaters and all exposed hot water pipes. Personally the 3 room apt I finished here I insulated all pipes, even ones to be concealed.
It save heat loss and quiets them. I have posted before how to go about buttoning up your homes probably found in the Green room.

When it is all said and done wood/ pellet stoves are zone heaters. Thats why I run 2.

I have attended the seminars given by the fire academy. I have wittness how fast fire can spread and realize what little time there is for safe exit. Bike Medic is a fireman he too has seen what I have. He will concure the dangers that exist and how quickly fire can spread without containment.

But why should I care, go ahead cut holes in your ceilings and floors. I will get more inspections and more remodeling work after the disasters. Living in a trailer besides your burntout home, is not my idea of comfort. Fighting with the insurance co is not the way I want to spend my day. Argueing with them to reinburse more, because some actions I took lead to further damage is not the position I want to be in. Telling them Joe blow from some internet site recomended as ways to keep warmer. Joe blow is not going to net you one more cent from the insurance co
 
I agree about the stupid return placement; our house was built circa 1982 and they spared all expense in building it. (We bought it much more recently, so we had no say in the matter.) Besides the top of the stairs we also have a return on the kitchen floor. I would think it would be a lot of trouble to add new returns except in the master bedroom, where I could just tap into the existing return duct. Our basement ducts are insulated and taped, but not sealed with mastic. Basically, it just doesn't get that cold in the DC area and until recently gas prices have been so low that even with minimal attic insulation and an old furnace it just didn't cost that much to heat. Our house is typical of so many here. Now that I am heating much more with (abundant free) wood, I expect my gas bill to be somewhat negligible; thus the ROI for heating-efficiency improvements is minimal. Call it the moral hazard of free wood. (Cooling, on the other hand, is expensive. If only they made a wood powered A/C!)

I assume you mean that the smoke detectors in bedrooms are electrically tied to all the others, so they go off in unison? If I just put a standalone detector in my bedroom and close the door, then it will be the last detector to go off if the fire starts downstairs, so that won't help as much. (Presumably the smoke itself would wake me up at that point).
 
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