How many watts is the cable rated for?

What minimum temperature do you want to maintain?

What is the low outdoor temperature during the season you want to use it?

Jim

We just got 8 inches of snow today, everything is closed (Yes!!!!!!!!), but.......

Can't find out how many watts the cable is rated for till the snow melts(couple days usually)The cable is in a barn, the door is blocked by snow........

Minimun temp. to maintain: 70* is the suggested temp. I want to start seeds and cuttings.

Lowest temperature during Spring would be an estimated 20*.

I can lay this out on a cement slab or over a dirt base. What might be better? Thanks for the reply...SB

Hi SandiB
This is my first time over here at
Garden experiments and your "hot
tips for gutter cables" caught my
eye.
I have a wnderfully simple system
that I designed for my cold frames. The heating cables that I
use on the floor are similiar to
gutter cables ,but they are the
type used to wrap water pipes.
Same principal just a little diff.
application. The cable itself is
25feet long and is 10 watts /foot.
The frames are 8'long x 4'wide.
About 3 1/2 feet high in the back
and 1 1/2 feet in the front. A
pretty good pitch. 250 watts is
plenty for my application.
The wiring is relatively simple
so I hope I don't turn it into a
"challenge" while trying to explain it.
On the back wall of the cold frame I mounted 2 separate electrical boxes which are connected by a short piece of
conduit.In the upper box I have a
standard line voltage thermostat
which is wired to and controls a
recepticle (weatherproof) mounted
in the lower box.
When the temp drops below whatever I have the thermostat set
for, it will send power to the
recept in which the heat cable is
plugged into. Also the power
comes to the coldframe from a
heavy duty rubber cord which I
plug int the back of the house.
I don't use it during the
coldest winter months for vegs.
I put my seedlings out at the
end of march/ beg.of April, and its looking more like April for
this yr. I usually like (so do
they) to start my seeds indoors
and then move them out when they
get their true leaves. It's a
really a simple system and it
works well.
I'm much anticipating that 1st
peep out of the tiny spring
peepers. They will probably stay
quiet until June, at the rate
things are warming up.
Do you have the gutter cables,
or are you going to purchase in the future. If you dont have them
yet, you might consider the type
for water pipes. Just a thought.
Joe in PA.

Hey there Wild By Nature, Thanks for the input. I will look into your idea. I have the gutter cable. We never installed it, so it is languishing alone in our barn. Did you lay your heat cables under the soil\sand and then place your flats on top of the whole thing?

We(Z4) will have a full month, yet, before I can put anything out. (just got 12 inches of snow!!) Plenty of time to organize a heat box for new transplants. Thanks for your idea. :) SB

12 MORE INCHES OF SNOW !!!!
That should be a pretty good nitrogen load for the soil, and if we
don't get too much rain to wash it
out.
I didn't go into too much detail on
the mini hot house construction.
The floor and the back is constructed of the 1/2 inch rigid
foam insulating boards.(foil backed) You can buy them in 4' x 8' sheets. very inexpensive. For the floor part I cut the 4x8 sheet in half (length
wise) thus making the floor thickness
1 inch, and I have the cable in a
sort of zig-zag pattern of which I
am carefull not to overlap at any
point. If the cable overlaps itself
it can cause it to overheat and in
turn fail. I've always been careful
with them, so i can say i did not havethat problem. I guess the same logicwould apply to gutter cables . Over-lapping can cause overheating.
If you decide to use your de-
icing cables in your cold frame, I
don't think that you should bury
them in the soil ,they are prob.not
designed for direct burial, also can
be easily damaged when working the
soil.
With the additional 12 inches of
snow, it looks like you'll have some
xtra planning time on your hands.
Another thing , I know a few folks that have the de-icing cables
on their gutters and they cause more
problems than they are worth,esp.
with heavy snow combined with freeze
thaw conditions. So maybe it is a
good idea to find a multi-use for
them. Keep us posted ! WBN

I stopped at Menard's tonight and checked out the heat cables. 30 watts for pipe cables vs. 400!! watts for gutter cables. Big difference. I think I could zigzag the cable and strategically place bricks between them, so the flats would hover over the cables...............SB

Sandi,
Was that 30 watts per foot or 30
watts for the entire cable? If it
is 30watts for the whole cable that is really low wattage,sounds
like that cable would have a
hard time melting a snowflake,let
alone roof ice !! Can you imagine
the heat given off by a 30 watt
light bulb ----- not much.
Your idea of laying the cables
between bricks sounds great. How
will you control the temp ? you
will have to be diligent when
you get warmer days.
Did all your snow melt ???
We might get an inch or 2 in
the mountains by tomorrow nite.Thats the outskirts of the Poconos,PA
jp

The 30 watts was for the pipe wrap that goes around water pipes. I'll have to go to Menard's again and check the details. I just saw "30 watts" on pkg. Can you tell I'm not an electrician? :) I can learn, though.

Our snow is still gracing our yard and patio, which is where I will be placing the transplant box. We don't usually get frost free days till at least April 15th. Even though we are Z4b, since we live near the Mississippi River, our planting season is 1 week ahead of Z5a, across the state where we used to live.

Controlling the temp: hoping that plugging in a night and unplugging during the day might work........ or
..........raising the box for ventilation might offset any overpowering heat. I guess I will have to make a few different setups and just do experiments to see what is most effective. I REALLY want my cuttings to survive this year. Everyone says how easy softwood cuttings are, but my cuttings haven't heard that. They always die!! Bottom heat is supposed to help. SB

Hi WBN,
I'm confused as to whether your box is 4'X 8' as you mention in your first post or 2'X 8' as it sounds like in your 2nd post. (It sounds as tho you are sandwiching the 2 layers of foam). Quoting from your posts....
"The cable itself is 25 feet long and is 10 watts /foot.
The frames are 8'long x 4'wide. About 3 1/2 feet high in the back and 1 1/2 feet in the front. A pretty good pitch."
-----------------------------------------------------------
"The floor and the back is constructed of the 1/2 inch rigid
foam insulating boards.(foil backed) You can buy them in 4' x 8' sheets. very inexpensive. For the floor part I cut the 4x8 sheet in half (length wise) thus making the floor thickness 1 inch."
I'm assuming the box is plywood or similar with foam insulation throughout?
Did you use glass or polycarbonate for the top?
Sorry for all the questions but it does sound like a great idea. I live in Montana and have to drive a long way to get the materials so I have to have a material list.
Thanks for any help,
LeRoy