Heating blankets?

[sashaeffer]

For those of us that have to build structures around our in the ground palms as anyone used heating blankets instead of Christmas lights hooked to a Thermocube to keep palm warm over the winter?

I have several in the ground and will soon have to protect them. Made in China incandescent C7 & C9 Christmas lights are terribly unreliable...and getting harder to find so thought about using heating blankets for a couple of mine just to see how well it works but thought I would ask here if anyone else has tried this method?

 

Scott

Omaha, NE  5b/6a

[Allen]

Sounds like a bad idea to me (Attract moisture??).  Use the smaller mini lights is a much better solution,  I never recommend the larger C7/C9 lights for a variety of reasons.  In 5a/6b you will most likely need to be using the box method which when insulated correctly can be heated with one 25-60watt equivalent heat source.    This can be a single or double fluorescent bulb or a string of mini lights.  Some people use heating cables which I also am not a fan of.  

 

https://www.homedepot.com/p/EcoSmart-100-Watt-Equivalent-T3-Spiral-Non-Dimmable-E26-Base-Compact-Fluorescent-CFL-Light-Bulb-Daylight-5000K-4-Pack-ESL23TM-5K-4-ESM/206135434

https://www.homedepot.com/p/Go-Green-Power-6-ft-18-2-Grounded-Indoor-Outdoor-Floodlight-Holder-GG-36001/304538096

https://www.lowes.com/pd/GE-String-A-Long-100-Count-20-6-ft-Clear-White-Incandescent-Plug-In-Christmas-String-Lights/50054667

 

Edited October 4, 2020 by Allen

[sashaeffer]

I use plastic 55 gallon barrels with vent holes drilled in along with leaving top barrel(if stacked) plugs off to allow venting. 
 

The barrels of spray foam on the inside for insulation. If I didn’t vent the barrels like I do I would have moisture issues

[Allen]

13 minutes ago, sashaeffer said:

I use plastic 55 gallon barrels with vent holes drilled in along with leaving top barrel(if stacked) plugs off to allow venting. 
 

The barrels of spray foam on the inside for insulation. If I didn’t vent the barrels like I do I would have moisture issues

I would use mini lights/thermocube in this type setup.  It's basically the insulated box method.   How many strings depends on your insulation.  100 mini=40W.  I'd guess 50 per foot of height if insulated well.  100/foot not insulated

 

https://www.powerstream.com/temperature-rise-in-an-electronics-enclosure.htm

Edited October 4, 2020 by Allen

[RyManUtah]

I’d think it would need to be well ventilated. The blanket may collect too much moisture. 
 

I’m tinkering with a concept of a wooden box with remote plug as you described for emergency arctic blasts. I’m learning towards mini ceramic snake “lamps”. They give off no light, just heat. However, I’m hoping to never need to install them.

[sashaeffer]

Mini lights would provide no heat for the space that I need warmed although I do use them for much smaller Palms with great success

[Allen]

1 hour ago, sashaeffer said:

Mini lights would provide no heat for the space that I need warmed although I do use them for much smaller Palms with great success

How many C7 or C9 bulbs have you used before in these enclosures?  Did you monitor temps with a remote thermostat?

[sashaeffer]

On 10/4/2020 at 2:02 PM, Allen said:

How many C7 or C9 bulbs have you used before in these enclosures?  Did you monitor temps with a remote thermostat?

Depends on the species of palm(cold hardiness) and if I have to use more than 1 barrel.  Thermocubes have been reliable but not Christmas lights or even reflector lamps with single incandescent bulbs in them.  Usually, I will always have two in any enclosure. Main and back up.  I can't monitor all, but I will select 4 and put a wireless thermometer inside the enclosure.

[Allen]

Here's a idea of what larger boxes might look like.  He is using fluorescent so they don't burn out.  This is probably 75 watts total with each bulb being 25 watts.  Two strands of the Mini lights is 80 watts or basically the same heat as he is using here.  He is zone 4.  I've used the mini's for 4 years on multiple palms and none have burned out.  I heat 10' tall non-insulated structures with them.  The C7 and C9 are prone to failure and will burn the palm if touching.  

 

https://www.houzz.com/discussions/2104139/inside-pics-of-palm-boxes-for-winter-protection

[sashaeffer]

Interesting. I wouldn't have thought the fluorescent bulbs would put out enough heat.  I have a few laying around still so will have to maybe leave one on for a while and check out the heat output.  Great share!

[Jimhardy]

if you have your lights on a thermocube they won't burn your

palms because they only heat the enclosure too 45F,they dont

stay on long enough to get hot- at the same time-they should not be touching anything

but even against the styrofoam I have had no issues because its cold and they don't stay

on that long....usually-the other issue is using a GFI outlet

without a ground which does not work.  I have had no issues with

lights and thermocube set up as long as you don't move them

while they are on because they will short out.

The bigger the space around the palm you need to heat

the more heat you need unless you triple up on insulation.

 

The nice thing about lights is you can unscrew them if you 

have to many etc but the thermocube solves a lot of issues like this.