Working the bugs out of heat circulation.

[smokee]

Being a part-time, half a$$ inventor, I decided to figure an efficient way of getting the heat generated by my new insert throughout our bi-level, 1600 sq ft home. No easy task considering our floor plan and the fact that the house was built in 1976 and only a little insulation was part of the building process. Lol.

The first task was to figure out the way both the gas furnace and the insert functioned together and how the heat is distributed - I would love to have the furnace not run at all when I'm burning. To do this I used a system that I built years ago when I was making a 12 volt electric cup holder that both heated and cooled a beverage. It's a small circuit board that plugs into a serial port on a pc and has 4 Texas Instrument temp sensors that are accurate to within +/- .05* F. When working on the cup holder, I used each sensor to monitor a different part of the cup holder. In my home, I used each of the four sensors at different locations throughout the house - one in the further most bedroom (which suffers immensely when wood is burning), one in the upstairs living room, one outside for outside temps and one in the family room with the insert. After 24 hours of running I generated this graph.

The idea is to experiment with different ideas and see what works best. This first 24 hours was the insert running and the furnace set to 70*f (the furnace thermo's about 2 degrees off) as a baseline then try running the furnace fan and various other ideas.

Don't misunderstand, I'm not obsessed in anyway about this. I've got the kids involved so hopefully they'll get something out of it. And, since its Januaury and cold in Pennsylvania, it's turned into a fun thing to do with the boys.

 

[taskswap]

Don't misunderstand, I'm not obsessed in anyway about this. I've got the kids involved so hopefully they'll get something out of it. And, since its Januaury and cold in Pennsylvania, it's turned into a fun thing to do with the boys.

Hey, even if you never get anything more out of it, getting the kids involved is huge. We've lost that "inventor" vibe and it's always good to see somebody say "what if" and then pass that on to the kids.

My crazy-ness is HotPi, an 8-zone heating controller that can manage wood, solar, oil and other inputs and outputs. I'm hoping it grows with me over time - but either way the thing that keeps me going is my oldest son's reaction when he helped me solder some of the pieces together. Highlight of his day became the highlight of my day. How many people do that anymore?

 

[smokee]

Hey, even if you never get anything more out of it, getting the kids involved is huge. We've lost that "inventor" vibe and it's always good to see somebody say "what if" and then pass that on to the kids.

My crazy-ness is HotPi, an 8-zone heating controller that can manage wood, solar, oil and other inputs and outputs. I'm hoping it grows with me over time - but either way the thing that keeps me going is my oldest son's reaction when he helped me solder some of the pieces together. Highlight of his day became the highlight of my day. How many people do that anymore?

That is good stuff. The kids take it in like a sponge then go back and try to do it their way with Legos. Lol. I love those guys and how they play - total entertainment. My boys are pretty young too so they still have a good bit of "cuteness" left. Our house is very male-centric so we do a lot of boy type activities. We always include mom. :msp_smile:

 

[Mac88]

Are you moving the air mechanically, or strictly by convection? A few duct fans and powered dampers should allow you to control the temp in each room, assuming you have some kind of duct system in place. You could control the furnace with a thermocouple at the insert (turn on the furnace when a certain set point is reached at the insert). Interesting project. There's a ton of simple computer boards out there capable of running the whole show.

 

[smokee]

Are you moving the air mechanically, or strictly by convection? A few duct fans and powered dampers should allow you to control the temp in each room, assuming you have some kind of duct system in place. You could control the furnace with a thermocouple at the insert (turn on the furnace when a certain set point is reached at the insert). Interesting project. There's a ton of simple computer boards out there capable of running the whole show.

There's a bunch of options in this house. I'm running the furnace fan by itself now and will see what that does. The people that lived here before us had a coal stove down here in the late 70's. they cut a hole in the cold air return and put in a closable grate. I've run the furnace fan with a ceiling tile moved to the side and the "grate" opened but it didn't seem like it did as much as I thought. That's the reason for setting up the pc, it'll pick up slight changes. I'd like to try a ceiling fan above the front door too - upstairs ceiling level where the hot air from downstairs rises.

If I can get a few weeks of entertainment out of it ill be happy and if there's benefit, all the better.

 

[saw dog]

Hi
If you create grilled openings in the second floor floors through the ceiling in the room below you will get gravity heat distribution and the colder up stair rooms will benifit greatly as long as you leave the doors open to the rooms above and below. Gravity was all there was before electricity was avaliable to run fans. Try it you will like it. Grills are avalibale in various sizes, install one in the floor and one in the celing directly below the one in the floor above. The grills need to be installed next to the out side wall where possibile. Heat rises and the cold air falls back to the heat source via the stair opening leading to the second floor. It takes a few hours to achive complete rotation, you will be suprised how even the various room temps. become.

 

[Marc]

Just curious, do you know what the temp sensors are? Thermocouples, RTDs or thermistors? All of those depend on fairly sensitive changes in resistance or voltage to determine temperature, so make sure if you're using long wire runs from sensor to your daq, you're not getting reading drift from resistance/voltage drop. In the range you're reading thermocouples and RTDs should be linear with temp so you could build in an offset to your software if you had to but thermistors are non linear so you can't do that with them.

A lot of times you can find digital temperature measuring daq and sensors on fleabay for next to nothing, a lot of used lab equipment goes up there. Usually with some type of common interface like serial or USB. Only if you really want to go crazy with it. Careful, it can be addicting, like so many other things.

 

[smokee]

Furnace fan running with the ceiling grate open in the insert room's putting up the best numbers.

 

[kd460]

Being a part-time, half a$$ inventor, I decided to figure an efficient way of getting the heat generated by my new insert throughout our bi-level, 1600 sq ft home. No easy task considering our floor plan and the fact that the house was built in 1976 and only a little insulation was part of the building process. Lol.

The first task was to figure out the way both the gas furnace and the insert functioned together and how the heat is distributed - I would love to have the furnace not run at all when I'm burning. To do this I used a system that I built years ago when I was making a 12 volt electric cup holder that both heated and cooled a beverage. It's a small circuit board that plugs into a serial port on a pc and has 4 Texas Instrument temp sensors that are accurate to within +/- .05* F. When working on the cup holder, I used each sensor to monitor a different part of the cup holder. In my home, I used each of the four sensors at different locations throughout the house - one in the further most bedroom (which suffers immensely when wood is burning), one in the upstairs living room, one outside for outside temps and one in the family room with the insert. After 24 hours of running I generated this graph.

The idea is to experiment with different ideas and see what works best. This first 24 hours was the insert running and the furnace set to 70*f (the furnace thermo's about 2 degrees off) as a baseline then try running the furnace fan and various other ideas.

Don't misunderstand, I'm not obsessed in anyway about this. I've got the kids involved so hopefully they'll get something out of it. And, since its Januaury and cold in Pennsylvania, it's turned into a fun thing to do with the boys.

Those numbers are pretty much what I get with my colonial home. Darn near exact temps in the upper floor and the main floor where my insert is. I don't have any grates or use the blower on my furnace. I just use a few small walmart fans to move the cool air out of the bedrooms and down the stairs to the main floor where the wood burner is.

I like the graph. Nice work. I just used some good old fashioned thermometers to check my temps. KD

 

[smokee]

Those numbers are pretty much what I get with my colonial home. Darn near exact temps in the upper floor and the main floor where my insert is. I don't have any grates or use the blower on my furnace. I just use a few small walmart fans to move the cool air out of the bedrooms and down the stairs to the main floor where the wood burner is.

I like the graph. Nice work. I just used some good old fashioned thermometers to check my temps. KD

I used thermometers and they worked fine. I had this setup and figured we'd make a project out of it.

Without a doubt, the furnace fan with a cold air return vent to open downstairs worked the best. I did a run last night where I started out with nothing then added one thing at a time. I started the fan after a couple hours then opened the grate in the cold air return. It's running now - I save out the logger file around 8 and crunch the numbers.

I really have to see how much energy the fan uses too.

 

[kd460]

The problem I have with using my furnace blower is the return air circulates through the ductwork located in the basement of my home (where the furnace is located). If I used my furnace blower it would cool the air too much.

My basement is cold because the furnace never runs because the wood burner is run 24-7 and does a good job of heating the living spaces.

Kind of a catch 22 I guess but my set up works. My basement will get down to about 60 degrees. I literally go down to my man cave to "chill out". Watching a ball game or listen to tunes, etc. At least the beer stays cold. KD

 

[smokee]

The problem I have with using my furnace blower is the return air circulates through the ductwork located in the basement of my home (where the furnace is located). If I used my furnace blower it would cool the air too much.

My basement is cold because the furnace never runs because the wood burner is run 24-7 and does a good job of heating the living spaces.

Kind of a catch 22 I guess but my set up works. My basement will get down to about 60 degrees. I literally go down to my man cave to "chill out". Watching a ball game or listen to tunes, etc. At least the beer stays cold. KD

Exactly what I'm finding. My downstairs is where the insert is so the family room with it is warm and the laundry room where the furnace is isn't very cold either but it's enough to mitigate most of the heat it's circulating. At least that's what I thought but the sensors are sensitive enough to show me otherwise. I also thought about sucking the air in directly above the fireplace using a home made fan system and pushing the heat through the warm air ducts and forego the furnace fan.