'trying' to heat crawspace/ max LOW temp??

[Elicit]

Hello, we had a new stove installed this year and it is AMAZING!! Clearly the stove that came with our home had seen better days... My issue now is trying to circulate enough of our wonderful wood heat from the main floor to the crawlspace as the ambient temp now makes the thermostat for the furnace redundant. ;0 )
I have the furnace fan running constantly and although it helps prevent us from melting by circulating the cooler air from downstairs, my wireless remote temp guage downstairs has me thinking that not enough heat is making its way down. I have also enlisted the help of a tower air purifier positioned beside the stove pointed in the direction of the closest return, The furnace, water softener and pump are all down there so the temp is something to be aware of. I currently have a temp alarm set to -10 on my remote device but the idea of having to crank the furnace over the ambient temp in order to heat the crawlspace is ridiculous!! ;0 (
Without any major construction (adding a return closer to the stove etc.) I am looking for ideas on how to move more heat through the return(s).

Additionally, I am looking for general ballpark temps as the max LOW before freeze for PEX piping.

*we have never had an issue with freezing in years past but it is clear now that the inefficiency of the old stove would have ensured the furnace kicked on overnight*


Some deets I am sure I will be asked for:
Open concept main floor with well positioned stove (PE Alderlea T6)
propane forced air furnace with 2 air exchange units on main floor (neither close to the stove)
wood foundation on bedrock (can stand sort of and walk in crawlspace) crawlspace is dry all year
PEX piping water lines.

thank you in advance for your time and info

 

[Highbeam]

So you say crawlspace. That's a regional term. In my area, and under my home we have a crawlspace which literally must be crawled in to move around. It has a dirt floor and is ventilated to the outside. Some folks call basements crawlspaces. They have lights, finished ceiling, concrete floor, etc. What is yours?

What are you worried about freezing down there? PEX is what I have and is the material most suited to freezing without damage. It will freeze up of course but not burst. Now the fittings can't withstand the freeze so if your plumber used fittings anywhere (not all do BTW) then you need to provide heat or insulation for those areas. Just last week I was in my crawlspace insulating my pex plumbing system that I installed over the summer. Pretty easy.

Just how cold is it getting down there?

 

[Elicit]

So you say crawlspace. That's a regional term. In my area, and under my home we have a crawlspace which literally must be crawled in to move around. It has a dirt floor and is ventilated to the outside. Some folks call basements crawlspaces. They have lights, finished ceiling, concrete floor, etc. What is yours?

What are you worried about freezing down there? PEX is what I have and is the material most suited to freezing without damage. It will freeze up of course but not burst. Now the fittings can't withstand the freeze so if your plumber used fittings anywhere (not all do BTW) then you need to provide heat or insulation for those areas. Just last week I was in my crawlspace insulating my pex plumbing system that I installed over the summer. Pretty easy.

Just how cold is it getting down there?

It is a crawl space as you only access it from the outside and if you want to access any of it other than the perimeter inside, you need to crawl.
So far it has only gotten to -13. I am more concerned about the electrical down there. ie. Furnace, water softener etc.

 

[Boiler74]

Maybe you can get by with thermostatically controlled outlets that plug into an outlet and then you can plug in an oil filled space heater. They have them at different "on" temps. So if the temp in the crawl dipped to that set temp, the space heater would kick on. You need to make sure the space heater is the oil filled kind, not the exposed hot wire kind. And that it will come back on to a set point when the power returns. Some will default to "off" when the power is turned back on.

Like this
http://www.amazon.com/Farm-Innovato...=1448905699&sr=8-2&keywords=thermostat+outlet

 

[begreen]

Are the crawl space walls and rim joists caulked, sealed and insulated? That can really help keep temps down there above freezing.

 

[Highbeam]

I can't believe that in Canadia, they would put water softeners and other plumbing exposed in an unconditioned crawlspace.

Most crawlspaces such as this in my area are ventilated. As in, cold air can blow right through it. Only in recent times have folks experimented with sealing off a crawlspace. If yours is ventilated then sealing it up is an option but there is more to it than just closing the vents.

The electronics won't freeze. If your furnace holds water in a condensate drain system then that water might freeze. You haven't said.

That water softener could freeze and be a huge problem.

With the goal of keeping that crawlspace from freezing you have some options. Adding a heater on a thermostat, heat tape, or running the furnace occasionally.

 

[Elicit]

I can't believe that in Canadia, they would put water softeners and other plumbing exposed in an unconditioned crawlspace.

Most crawlspaces such as this in my area are ventilated. As in, cold air can blow right through it. Only in recent times have folks experimented with sealing off a crawlspace. If yours is ventilated then sealing it up is an option but there is more to it than just closing the vents.

The electronics won't freeze. If your furnace holds water in a condensate drain system then that water might freeze. You haven't said.

That water softener could freeze and be a huge problem.

With the goal of keeping that crawlspace from freezing you have some options. Adding a heater on a thermostat, heat tape, or running the furnace occasionally.

It is a crawspace however it is surrounded by a properly installed/sealed wood foundation. You have to enter through a modified door and it is lighted. The perimeter inside is poured concrete and under the center of the house is concrete footings and clean chunky gravel (?).
As I mentioned, the furnace probably ran quite often in previous winters due to the old wood stove not running efficiently. The new stove is almost too efficient and I am trying to figure out how to NOT fire up the furnace just for the crawl space. I would literally have to crank the thermostat waaaaaay up to kick it on and it would be pushing more heat into the already warm main level.

 

[Warm_in_NH]

A good early warning sign, that I think I read on here somewhere, is to put 1/2 empty (or full, depending on your point of view) water bottles in the coldest places in your crawl space. If they start to ice over, you know you need additional heat. So far so good.
I had similar concerns when I installed my stove 3 Years ago, I bought an electric heater and a thermal cube (Google it, my phones new os is lucky about linking things, sorry) it never kicked on, but it's nice insurance for under 70 bucks.

 

[begreen]

Are the foundation and sills fully insulated?

 

[Elicit]

A good early warning sign, that I think I read on here somewhere, is to put 1/2 empty (or full, depending on your point of view) water bottles in the coldest places in your crawl space. If they start to ice over, you know you need additional heat. So far so good.
I had similar concerns when I installed my stove 3 Years ago, I bought an electric heater and a thermal cube (Google it, my phones new os is lucky about linking things, sorry) it never kicked on, but it's nice insurance for under 70 bucks.

I actually have a couple of cases of water down there. Will keep an eye on them every time I add salt to the softener. I am familiar with the therma cube (use them in the barn). I think I may do that with an oil heater if it dips too low. Thanks for all the replies everyone!!

 

[Stubborn Dutchman]

I have a similar situation. My home has central heat via propane furnace located in the crawl space. Heat coming of the supply duct work was sufficient to keep things from freezing down there. Right after I moved in I installed my Jotul F600 so the furnace never kicked on any more. Electric space heaters cost too much to run so I installed a low temp thermostat and set it at 35 degrees (its lowest possible setting). I also cut in two heat register grills in the supply near my water captive air tank. The propane furnace didn't come on often last year but did when it had to. Problem solved since I need to do at least one propane refill every year to avoid a service fee. (Still need propane for the water heater and kitchen stove.)

 

[bag of hammers]

Are the crawl space walls and rim joists caulked, sealed and insulated? That can really help keep temps down there above freezing.

I have pretty much this setup, no heat in the crawl, roughly 3' high, upstairs temps are mid to high 50's (when I'm away, Rinnai direct vent unit takes care of the no freeze) and 70's when I'm there running the stove. Last 2 years we had some of the coldest winter weather on record, crawl space never dipped below 45 deg F. I sealed the vents and put a good dehumidifier down there, so far so good.

 

[begreen]

We do too, that's why I asked. I insulated the all the crawlspace walls and now it rarely gets below 60F down there even after multiple days in the teens at night and 20s in the day.

 

[HisTreeNut]

I have a crawlspace as well, vents are blocked due to a dehumidifier, & a vapor barrier on the entire space [2200' of crawlspace]. The space varies from 3 to 5 feet and the temp is usually in the 50's down there...60's in the summer time and the humidity holds around 42%. When we had a really frigid cold snap last year and the temp got to about 40 degrees in the crawlspace, I added heat easily. I flipped on the lights we installed [old fashioned bulbs not florescents or LED's]. Took the temperature up about 5 degrees after about 6 hours. Not terribly efficient, but it worked.

 

[Tumpin' Wood]

You likely have very little to worry about. Our place in Temagami is on posts and has an insulated (R12) plywood skirt around it. Enough heat passes through the uninsulated floor to prevent pipes from freezing most of the time. In eight years we froze up a dozen times. I took the torch to the pipe coming into the crawlspace (it's at floor level) and normally had running water in 15 minutes. If I couldn't find the blockage, I turned on the electric heater and let it run for the day.