How to get the heat downstairs

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give your daughter the phone..lots of hot air then?
 
elkimmeg said:
Oregon what it is already done One down fall of central air heat is its zoning Many times one system delivers the entire home from One thermostat location,
here is a simple way of zoning it what if all grills were dampened grills One could close down the ones near the stove forcing more heat to the outer locations By having a remote thermostat that activated the burner only the rooms with open grills would get heat. That's one way a DIY could achieve jeeping re, mote to stove rooms warn.

The second way would be to split the duct work and control it with a thermostat zone damper this would also help the AC end of the HVAC system by having smaller run zones and two thermostats locations to reflect temp differences. Naturally dampened grills within systems would give you further control at heating the areas you most need it

Basement main furnaces supplying the second floor are woefully inadequate. It would be prudent to cap that system off and have a second attic furnace and zone for that second floor level.


then there is efficiency of design, A whole other topic most HVAC systems are poorly designed and installed the ductwork is not sealed correctly and routing just plain------ , well you know this is a family forum fill in your own description. Energy cost are two fold a cheaper source and a efficient delivery system. To me up, to 35% loss to transmission has to be improved.

I looked around at zone systems and don't see what I want - what I see are zone thermostat systems that are designed with dampers to bias the heat delivered from the furnace to colder areas of the home. Alternatively, they average temperature sensor readings to determine when to call for heating.

What I desire is a system which senses when it is appropriate for heat content in the room containing my fireplace insert to be distributed throughout the house using the existing ductwork. I don’t want to spend the money on dampers, I just want the fan to turn on low to distribute the warmth about the house when the temperature difference warrants it. My furnace has a two speed blower - so blowing on “low” is a low-watt affair.

Eliminating leaky ductwork from the equation is one benefit of a fireplace insert. And I gave this alot of consideration when purchasing the fireplace insert I have - no loss in the ductwork that traveled through my uninsulated crawl space. But, I already sealed and insulated my ductwork and had a friend who does HVAC come in and redesign and re-route the main trunks to well distribute the supply. I was probably losing 15-20% in efficiency prior to these upgrades.

I am still hunting around the web for what i want. The only thing I have seen that will remotely do what I want are thermostats that allow for fan operation for a given # of minutes per hour (15, 30, 45, etc.). At least it won't be running all the time...

jeff
 
Normally I don't recommend this setup because of heat loss in the ductwork. But it sounds like you have prepared the system for trying this out, so here it goes. Other than the issue of fan speed, this might be an easy problem. I would think a simple thermostat that makes on temp rise (this is normally the AC cooling mode) would work here, assuming that the furnace has a manual fan mode for the thermostat. If it does, then wire the cooling mode thermostat across the fan terminal (typically green wire) and common (typically red wire) on the furnace thermostat. When the stove AC mode thermostat calls for cooling it will close the circuit across the fan terminals. When the room becomes too cool (no cooling needed) it will break the circuit.

If you try this, be sure that you have the color coding for the heating system fan circuit and common correctly identified first. Not every system is installed according to color code and often there are other colors substituted.
 
BeGreen said:
Normally I don't recommend this setup because of heat loss in the ductwork. But it sounds like you have prepared the system for trying this out, so here it goes. Other than the issue of fan speed, this might be an easy problem. I would think a simple thermostat that makes on temp rise (this is normally the AC cooling mode) would work here, assuming that the furnace has a manual fan mode for the thermostat. If it does, then wire the cooling mode thermostat across the fan terminal (typically green wire) and common (typically red wire) on the furnace thermostat. When the stove AC mode thermostat calls for cooling it will close the circuit across the fan terminals. When the room becomes too cool (no cooling needed) it will break the circuit.

If you try this, be sure that you have the color coding for the heating system fan circuit and common correctly identified first. Not every system is installed according to color code and often there are other colors substituted.

Now that's clever - and can be done with a cheap simple thermostat too...

And my friend ran new stat wire for me when he installed my AC - so all should be good there.

Along the same lines, it sounds like it wouldn't be a problem to use stats in heating mode and put multiple thermostats around the house and wire them in a similar manner - and if any of them hits the trip point, then it will kick on the fan . The only issue I see is resistance of the wire and voltage drop on the fan control line, the furthest stat would be 80+ feet from the furnace. Is there a rule of thumb limit to the length of stat wire one can run from thermostat to the furnace?

thanks!,
jeff
 
The best - and perhaps only - way to really move decent heat down from a freestanding stove is to install a small hot water loop using a stainless or other heat exchanger in or on the stove, and then install a pump and a kick space heater downstairs. Water can move down much easier than air.

As has been mentioned, there are LOTS of potential air balance problems with the hoods, etc......although I suppose a flex metal pipe connected to a hot air blower outlet on the stove would do the job somewhat....but I don't know many people who would want that in the living room (all nighter stoves had this sort of small round outlet, among others).

In general, the rule applies - heat downstairs with stove downstairs.
 
I'm going to try building an enclosure in a corner near the wood stove containing a 6 or 8 " duct to about a foot below the ceiling with an inline fan blowing straight down into the basement. on the other side of the basement I'm going to have another duct running from near the floor of the basement to a vent in the floor of the heated room also with a fan of the same cfm rating to prevent chimney draft problems. I haven't worked out all the details yet.

Now which wood stove???
 
Oregon Fire said:
BeGreen said:
Normally I don't recommend this setup because of heat loss in the ductwork. But it sounds like you have prepared the system for trying this out, so here it goes. Other than the issue of fan speed, this might be an easy problem. I would think a simple thermostat that makes on temp rise (this is normally the AC cooling mode) would work here, assuming that the furnace has a manual fan mode for the thermostat. If it does, then wire the cooling mode thermostat across the fan terminal (typically green wire) and common (typically red wire) on the furnace thermostat. When the stove AC mode thermostat calls for cooling it will close the circuit across the fan terminals. When the room becomes too cool (no cooling needed) it will break the circuit.

If you try this, be sure that you have the color coding for the heating system fan circuit and common correctly identified first. Not every system is installed according to color code and often there are other colors substituted.

Now that's clever - and can be done with a cheap simple thermostat too...

And my friend ran new stat wire for me when he installed my AC - so all should be good there.

Along the same lines, it sounds like it wouldn't be a problem to use stats in heating mode and put multiple thermostats around the house and wire them in a similar manner - and if any of them hits the trip point, then it will kick on the fan . The only issue I see is resistance of the wire and voltage drop on the fan control line, the furthest stat would be 80+ feet from the furnace. Is there a rule of thumb limit to the length of stat wire one can run from thermostat to the furnace?

thanks!,
jeff

You'll still want to be careful of the wire color. Your friend may have had to make compromises based on the colors available in the cable.

You don't want to use the heating side of the thermostat. That completes the circuit when the temp falls. You want to use the cooling side of the thermostat that makes the circuit when the temp rises above the set point.
 
BeGreen said:
Oregon Fire said:
BeGreen said:
Normally I don't recommend this setup because of heat loss in the ductwork. But it sounds like you have prepared the system for trying this out, so here it goes. Other than the issue of fan speed, this might be an easy problem. I would think a simple thermostat that makes on temp rise (this is normally the AC cooling mode) would work here, assuming that the furnace has a manual fan mode for the thermostat. If it does, then wire the cooling mode thermostat across the fan terminal (typically green wire) and common (typically red wire) on the furnace thermostat. When the stove AC mode thermostat calls for cooling it will close the circuit across the fan terminals. When the room becomes too cool (no cooling needed) it will break the circuit.

If you try this, be sure that you have the color coding for the heating system fan circuit and common correctly identified first. Not every system is installed according to color code and often there are other colors substituted.

Now that's clever - and can be done with a cheap simple thermostat too...

And my friend ran new stat wire for me when he installed my AC - so all should be good there.

Along the same lines, it sounds like it wouldn't be a problem to use stats in heating mode and put multiple thermostats around the house and wire them in a similar manner - and if any of them hits the trip point, then it will kick on the fan . The only issue I see is resistance of the wire and voltage drop on the fan control line, the furthest stat would be 80+ feet from the furnace. Is there a rule of thumb limit to the length of stat wire one can run from thermostat to the furnace?

thanks!,
jeff

You'll still want to be careful of the wire color. Your friend may have had to make compromises based on the colors available in the cable.

You don't want to use the heating side of the thermostat. That completes the circuit when the temp falls. You want to use the cooling side of the thermostat that makes the circuit when the temp rises above the set point.

I understand what you are saying concerning the cooling side of the stat. Please understand that I am thinking about it in two ways.

The first is the way that you are, with a single additional cooling mode thermostat in the room with the woodstove. The stove is in the living room at center of the single story ranch home that is 2300 square feet. And when the room with the wood stove is sufficiently warm, then the cooling mode thermostat will complete the circuit to enable continuous fan operation and the warm air will be distributed around the house. This would have a side benefit of keeping this room from becoming excessively warm.

The second way is to put a heating mode thermostat in my daughters cold bedroom. When the bedroom drops below a certain temp - the circuit will be completed and the air will be circulated around the home to equalize the temperature. With this second method, I could possibly put another heating mode thermostat in my master bedroom. When either room got cold - the fan would kick on and distribute warm air from the living room to these rooms.

On the issue of the stat wire - thanks for the heads up on the color codes - I'll double check it. (I am an electrical engineer...)

Thanks again, I was ready to spend a bunch of money on a network controllable thermostat along with networked sensors. You saved me money and given the simplicity of your solution, it will be more likely to "work" out of the box.

jeff
 
Just to warn, I once did the whole ducting system for my wood stove and even did the "kitchen hood" that floated above it. The stove was in my basement, I figured any hot air rising off it would collect into the hood and flow from there through the ducts to the upper floors of my house. It was a huge letdown, in the end the basement only stayed 5F cooler and the upper floor was 5F warmer, I still had to keep the basement around 80F and my upper floor lingered around 60F. I added a fan, didn't make a big difference. So, I can't imagine how trying to get the heat down will work. Honestly, I think the main floor of my house was kept warm by me keeping the basement around 80F it heated up the ceiling of the basement (or the floor of the main level looked another way) and it was like radiant floor heating without the radiant tubing. The upper floor was terribly cold, I would have done better with a convection wood stove for what I was trying to do... at a minimum I recommend at least you look at convection stoves. Most today labelled "convection" today are some type of hybrid. The Englander's in particular can have side & rear heat shields which reduce the radiant energy and convert it to additional amounts of convection. For what you want to do, the Englander with rear & side heat shields is a start and the blower.
 
Here is a way this guy accomplished pushing heat downward
 

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A lot of the EPA ZC fireplaces have knockouts in the outer shell and kits (insulated flex pipe + blower) to transfer hot air around. I got one thinking I could run it to the central air plenum in the basement, but it doesn't transfer enough heat and my ductwork has losses. It blows plenty of heat, however, to heat my basement if/when I insulate and finish it. The return is effectively the basement stairwell, which opens to the room with the fireplace. But here I'm sucking hot air directly from the heat exchange chamber, literally inches from the firebox. Hard to see how that could be replicated with a freestanding stove.
 
Is there a significant difference in room AIR temperature between one heated with convection and one with radiant heat?

If you put a thermometer behind a insulated heat shield near the stove would that give an accurate measurement of the air temp - the radiant factor which isn't going to go down the duct?

How much difference is there between the air near the floor and the air near the ceiling of a room heated with either?

If the air isn't hot, then blowing it downstairs is useless.

The duct that I'm thinking of using is either insulated round hvac or pvc pipe 6 or 8" round with inline fan blowing straight down. No turns = very little loss of volume. I'm not sure exactly how many cfm I need to move but I would think 300-500 might do it.
 
It seems as if the summary advice from experts here is not to do it at all.

At least that is what I read. And, if so, it's tough for use to tell you the best way to do it! We have yet to run across a situation where this works well.

I have moved heat to others areas of a ranch house using a bathroom-type exhaust fan in the ceiling of the stove room and a short run of ductwork dropping into another - but this was really taking heat from the room as opposed to directly from the stove - also, the results were nothing spectacular.

I say get an oil-filled electric radiator or something like it for the basement area.
 
you might also want to check with your building dept so that you include the necessary safeguards and permitting because after all .you are creating an un protected open in either you floor
or ceiling reducing the natural containment values of these structures
 
Webmaster said:
I say get an oil-filled electric radiator or something like it for the basement area.

Craig, any reason you say oil-filled electric radiator in particular? Any experience telling you whether they're more efficient or safer than simple elect space heaters or std 220 baseboard? I'm resigned to doing something as well and have looked at those vs propane and other 110 elect sources. Have they worked well for you? They sound like the ticket if you're not looking for quick heat.
 
Oil and hotwater electric heaters safer, especially if there are combustibles like curtains nearby. Some oil filled heaters have timers so that they automatically turn off/on at a preset time. But any electric heater would work, especially if the TV area was partitioned off either permanently or temporarily for the winter.
 
We have the same situation as the original poster, daughters room is in basement. We went and picked up a DeLonghi oil filled radiant heater with a timer and it will keep it 67-70 deg. down there no problemo. to help make up for the extra power usage we changed all the light bulbs to compact florescent, works great.
 
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