Cold Air Return?

Cold Air Return?

PostBy: Qball On: Thu Nov 20, 2008 11:04 am

I know this has been discussed a million times, and I know the best way I need to make my cold air return is piped back to the blower on my stove. I need to go from the furthest part of the house and logistically and cost wise I am trying to avoid this. If I place a register in this furthest room with a duct to a few inches off the cellar floor, Will this allow the cold air to escape from that room? I could also place a fan in this duct or resister. To run the pipe to the stove I have tons of old pies, wires, a doorway, before I get to the room with the stove. I do not want a duct running all the way back. If you look at this post you will see the ducts I use to get the heat up:

Ducting heat

I currently leave the basement door open which is working well, excpet the furthest room (where the oil furnace thermostat is) is staying 7-10 colder.

Thanks!
Qball
 
Hot Air Coal Stoker Stove: Keystoker Koker
Coal Size/Type: Rice

Re: Return

PostBy: BTUs On: Thu Nov 20, 2008 12:33 pm

I think it would work by placing a register to the basement, getting the cold air out of the room is a must, but here is something to consider which I've discovered over the past several days. Keep in mind that I'm a rookie at burning coal, but I too was using my basement as a return, just by opening my kitchen door to the basement. It was taking me 3 hours with the stove at 90% to raise the temperature upstairs from 65 to 68 and the basement was the same temperature as upstairs.

I decided to bite the bullet and shell out money for duct pipe and fittings and piped my whole house return duct directly to the inlet of the convection fan. Now it took 35 minutes to raise the temp upstairs from 65 to 68 (stove at 90%). I was shocked. I guess I was heating up the basement with my return, which doubles the square footage to heat my house. Realizing this, I opened up the basement window to allow fresh air in. Opening the window stopped any upstairs air from returning and heating the basement. Now it takes 25 minutes to raise the temp upstairs from 65 to 68 (stove at 90%). I guess I'll bite the bullet once again and shell out more money to add a supply from outside to the combustion blower and near the baro dampener.

Have fun
BTUs
 
Stove/Furnace Make: Alaska
Stove/Furnace Model: Channing III

Re: Return

PostBy: av8r On: Thu Nov 20, 2008 1:07 pm

My basement is considerably colder than the coldest rooms. I don't think my returns are doing anything.
av8r
 
Hot Air Coal Stoker Furnace: Leisure Line Hearth with twin turbos (sounds like it)
Stove/Furnace Make: Leisure Line
Stove/Furnace Model: Hearth model with twin turbos


Re: Return

PostBy: Dallas On: Thu Nov 20, 2008 3:33 pm

I used 6" flexible aluminum dryer duct from the return register to the stove room. It's easy to work with, cheap and does the job. I also, incorporated a duct fan in the line.
Dallas
 
Hand Fed Coal Stove: Modified Russo C-35
Other Heating: Oil Hot Air
Stove/Furnace Make: Russo
Stove/Furnace Model: Modified C-35

Re: Return

PostBy: LsFarm On: Thu Nov 20, 2008 4:02 pm

Hi Qball, it is worth it , like BTU posted, to spend the $$ for some ductwork.. I would not use the whole basement as a cold air return,, unless it is a family room or den that you want heated.. The dedicated duct will be MUCH more efficient at getting your upstairs warm, in the least time, with the least fuel burned..

Greg L
LsFarm
 
Stoker Coal Boiler: Axeman Anderson 260
Hand Fed Coal Boiler: Self-built 'Big Bertha' SS Boiler
Baseburners & Antiques: Keystone 11, Art Garland

Re: Return

PostBy: Qball On: Thu Nov 20, 2008 4:08 pm

OK if I go the flexible route, will it matter if it has turns where I negotiate around beams, pipes, doors.....
Qball
 
Hot Air Coal Stoker Stove: Keystoker Koker
Coal Size/Type: Rice

Re: Return

PostBy: Dallas On: Thu Nov 20, 2008 5:34 pm

It might have some effect, however it's a great alternative to solid duct work.
Dallas
 
Hand Fed Coal Stove: Modified Russo C-35
Other Heating: Oil Hot Air
Stove/Furnace Make: Russo
Stove/Furnace Model: Modified C-35

Re: Return

PostBy: the snowman On: Fri Nov 21, 2008 1:01 pm

I have a problem with getting the heat from my coal stove which is located at the far end of the house to the last two rooms on my first floor. My coal stove is on the first floor as well. I was thinking of taking an existing hot air duct in the furthest room and turning it into a cold air duct and piping it to come through the floor next to the coal stove. I'm thinking this will allow the cool air from the last two rooms to move back to the stove and allow the warm air to circulate in. I already have a fan in the doorway moving warm air towards the last two rooms. Any thoughts on this before I go cut a hole in my hardwood floor next to the stove and insert a vent.

wayne.
the snowman
 
Hand Fed Coal Stove: Jotul 507
Coal Size/Type: Nut, Stove coal, Egg coal

Re: Return

PostBy: LsFarm On: Fri Nov 21, 2008 2:43 pm

Hello wayne, I believe you will find that your plan works well.. even better if you can hook the duct via flex pipe or elbows either to the inlet or near the inlet of the distribution fan of your stove.. You want positive movement of air from those distant cold rooms.. removing the cool air will allow the hot air to replace it..

Let us know how it works for you..

Greg L.
LsFarm
 
Stoker Coal Boiler: Axeman Anderson 260
Hand Fed Coal Boiler: Self-built 'Big Bertha' SS Boiler
Baseburners & Antiques: Keystone 11, Art Garland

Re: Return

PostBy: BTUs On: Fri Nov 21, 2008 3:22 pm

Hi wayne.......funny you wrote this. I was thinking of the same thing last night if I decided to move my stove from the basement to the first floor. I don't have any experience with this set up, but I was thinking of actually hard piping the inlet to the convection fan to the house supply ductwork, so I can pull cold air in from all rooms (maybe too much), or just pull from the furthest rooms by disconnecting rooms closer to the stove. Just an idea you could also put a tee (with a dampener) off the inlet to the convection fan. One end hard piped to the return from the last two rooms, and the other end pulling from the same room as the stove (modulate with dampener and set it). Modulating the dampener will pull more or less air back from the two rooms. May also want to check your fan amperage to make sure your not putting too much stress on the motor.
BTUs
 
Stove/Furnace Make: Alaska
Stove/Furnace Model: Channing III

Re: Return

PostBy: MrMikie On: Fri Nov 21, 2008 3:58 pm

Let us know how you make out, as I am doing something similar but do not have a basement.

Who knows when I am done I may have to just move it, :lol:

http://nepacrossroads.com/about7933.html
MrMikie
 
Stove/Furnace Make: Leisure Line
Stove/Furnace Model: Pioneer LE

Re: Cold Air Return?

PostBy: the snowman On: Fri Nov 21, 2008 11:56 pm

Today I looked at the possibility of reducting one of my existing hot air ducts and I believe I can make the cold air return exit about six inches from my distribution fan I have for the stove. My stone and tile work prevents me from getting any closer. I don't believe I will need a damper due to the fact that the cold air return will have to travel about thirty feet to reach the stove location. I believe I might have to install a variable speed fan to push the cold air that kind of distance. The real problem I see with all of this is: Most of the thirty feet of duct work has to be done in a crawl space under my living room. The cellar of this old farm house was not extended when the additions were added on sometime in the early fifties. So, tomorrow I will spend the day working on the cold air return. I need to get the heat moving into the last two rooms as soon as possible. My outside temps have been down to zero at night and only twenty during the day all this week. I have thirty six inches of snow on the ground with a possible twelve more by the end of the weekend. The zero degree weather makes the last two rooms temps fall to 59-60 F at night. I have had to run the furnace to keep those two rooms warm. I will keep everyone up to speed as to how I make out. Thanks for the input.

wayne.
the snowman
 
Hand Fed Coal Stove: Jotul 507
Coal Size/Type: Nut, Stove coal, Egg coal

Re: Cold Air Return?

PostBy: Qball On: Sat Nov 22, 2008 7:51 pm

Put a 6x12 register in the cold front room. Immediately feel cold air rushing down to the basement. I got 1 small piece of rigid 6" duct where I will put an in-duct fan near the register. I also bought some flexible 6" ductwork and will work on it soon. I left a small fan blowing down the register when I left for work. It will be interesting to see if the temp has risen in that room from just the register and fan. I also shut the basement door.........
Qball
 
Hot Air Coal Stoker Stove: Keystoker Koker
Coal Size/Type: Rice

Re: Cold Air Return?

PostBy: the snowman On: Sat Nov 22, 2008 9:33 pm

I reducted the one heat duct in the furthest room and have it exiting next to the distribution fan I have for the stove. I could feel the cool air moving up out of the vent next to the stove, however, I thought it was still a little low on volume so I put a small fan on the register in the far room blowing down into the now cold air return to the coal stove. It is now moving a lot of cold air, however, I still have a cold draft coming across the floor towards the coal stove which is coming from the last two rooms. I can feel the cool air slowly moving toward the cold air return in the furthest room. Maybe I was expecting this huge change since I spent the entire day crawling on my back, stomach, and knees under the house running solid duct work. Maybe it will take a little longer to get the flow flowing and I have just been a little impatient. Anyone have any thoughts. Thanks.

wayne.
the snowman
 
Hand Fed Coal Stove: Jotul 507
Coal Size/Type: Nut, Stove coal, Egg coal

Re: Cold Air Return?

PostBy: av8r On: Sat Nov 22, 2008 10:39 pm

Wayne, we have the same issue. Ranch style house, coal stove on the living floor and all the way at one end. My wife sits on the couch which is lined up with the hall way leading to the bedrooms and she can feel a draft coming down the hallway. That cold air has to go somewhere. My basement isn't really heated anymore with the oil boiler only working to heat domestic hot water so the basement is colder than the coldest rooms at the far end of the house. Even with 2 cold air returns in those rooms, there isn't much cold air falling into the basement so no convective current can pull the warmer air in the living room down the hallway and into those bedrooms. I'm going to put a small fan at the start of the hall and just blow some air in that direction to see if it helps. If the air where you're running the ducts is colder than the air in the rooms, I don't think the returns are going to work without a fan to move things along.
av8r
 
Hot Air Coal Stoker Furnace: Leisure Line Hearth with twin turbos (sounds like it)
Stove/Furnace Make: Leisure Line
Stove/Furnace Model: Hearth model with twin turbos