Snow Melt Programming

[ajd123]

I would like to create programming for the following:

Everyday at 10am turn on a specific light switch (controls snow melt cable) from: November 15 --> April 15

Everyday at 10am turn off a specific light switch (controls snow melt cable) from April 16 --> November 14

Have this repeat over and over again.

The purpose of it repeating everyday is in case someone turns it off by accident in the winter OR on by accident in the summer.

I can only figure out how to program it based on months, but not the middle of the month (see attached picture).

What would be the best way to do this?

Thanks

[msgreenf]

Use date not month 

[ajd123]

1 hour ago, msgreenf said:

Use date not month 

If I use this approach, I cannot schedule it to recur yearly.

[msgreenf]

[msgreenf]

@ajd123 ^^

[RAV]

Variable - IsWinter

November 15 set to true

April 15 set to false

daily at 10, if variable IsWinter true turn on switch, else turn off switch.

[ajd123]

1 hour ago, RAV said:

Variable - IsWinter

November 15 set to true

April 15 set to false

daily at 10, if variable IsWinter true turn on switch, else turn off switch.

I like this programming, thanks @RAV. 

Could not figure out the "else turn off switch" so I programmed as per the attached.

Does this look correct?

[msgreenf]

P no, this doesn't make sense. You're saying the variable when the variable changes but you never ever condition that's going to make the variable change

[ajd123]

1 hour ago, msgreenf said:

P no, this doesn't make sense. You're saying the variable when the variable changes but you never ever condition that's going to make the variable change

I see what you mean.  So where should the programming be placed so it triggers?

If I put all the programming in the scheduled event (see attached), would this do the tricK?

[msgreenf]

On a schedule? On a timer?

[ajd123]

2 minutes ago, msgreenf said:

On a schedule? On a timer?

See post above, is this what you mean?

[RAV]

Create 3 scheduled events & 1 variable
IsWinter - boolean

November 15th 12:01 am, repeat yearly
April 15th 12:01 am, repeat yearly
10am, repeat daily

Programming Tab - Scheduling
November 15th, set IsWinter to true
April 15th, set IsWinter to false
10am , if IsWinter is true turn on switch, else turn off switch

Similar for summer folk, holiday lights start/stop, etc.

[zaphod]

Shouldn't you also be checking for temperature?  This may depend on where you live, but I am in Toronto and there are lots of days in the winter where it is well above freezing.  It seems like a waste of energy to always have this on when the temperature may not call for it?

[eggzlot]

1 hour ago, zaphod said:

Shouldn't you also be checking for temperature?  This may depend on where you live, but I am in Toronto and there are lots of days in the winter where it is well above freezing.  It seems like a waste of energy to always have this on when the temperature may not call for it?

Agreed but it’s checking for temp and precipitation.   I’ve tried 2-3 drives and none had the ability to get that granular.  And some have been discontinued anyways.  For now I just use the timer agent - set it for a time and then the heated pads go on.  It’s a manual effort but when I watch the weather I’ll get the idea of when I want to turn them on (about 2 hours before the event) so I just do it quasi manually

what the OP is suggesting is just to do it regardless - again could be a waste of electric

[ajd123]

1 hour ago, zaphod said:

Shouldn't you also be checking for temperature?  This may depend on where you live, but I am in Toronto and there are lots of days in the winter where it is well above freezing.  It seems like a waste of energy to always have this on when the temperature may not call for it?

I am in Newmarket so I totally get your point. The product I use is called Heatline Paladin (They are a local company).  The cables heat up based on the ambient temperature so when it is warmer outside, they use very little electricity.

I use the cables primarily to keep downspouts from freezing up, so I don’t have that much linear footage of cable.

[zaphod]

2 hours ago, ajd123 said:

I am in Newmarket so I totally get your point. The product I use is called Heatline Paladin (They are a local company).  The cables heat up based on the ambient temperature so when it is warmer outside, they use very little electricity.

I use the cables primarily to keep downspouts from freezing up, so I don’t have that much linear footage of cable.

Interesting - but won't they still use a lot of electricity if it is 2-8C out.  Which is going to be the temp for the next 5 days, at least in Toronto.

[ajd123]

On 12/26/2024 at 10:13 PM, zaphod said:

Interesting - but won't they still use a lot of electricity if it is 2-8C out.  Which is going to be the temp for the next 5 days, at least in Toronto.

Here is the product: https://heatline.com/product/paladin-for-pipe/ 

Have a look at the product brochure.

I believe they warm to 50 degree Fahrenheit (10 degrees Celsius).  Since the cable is self regulating, it draws a lot less energy (watts per foot) when the ambient temperature is above zero.

At the moment I only have one 30' cable installed (which uses a maximum of 3 watts per foot per hour) to help with a downspout that froze over and fell off a couple years ago.  In a worst case scenario, I am using 90watts per hour which is not an issue for me.  With my current ToU (Time of Use) electricity charges, this runs me about $0.25 per day on weekdays and $0.19 per day on weekends if the cable is drawing the maximum wattage.

[Neo1738]

I have heattrak mats and have it set to month (Nov-March), temperature (<34F), precipitation(>0.1" expected that day). If you use temp as a variable no need to worry about day of the month and easy to repeat. Goes on for 24 hours then reevaluates the variables. If still variables still positive restarts the timer, if not then stops timer and turns off matts.

[ajd123]

On 12/26/2024 at 10:13 PM, zaphod said:

Interesting - but won't they still use a lot of electricity if it is 2-8C out.  Which is going to be the temp for the next 5 days, at least in Toronto.

Spoke with the manufacturer today and it looks like I goofed.  The cables run at 5 watts per foot if the ambient temperature is 50 degrees Fahrenheit.  If the ambient temperature is below 50 it will run at a higher wattage, if the ambient temperature is above 50 it will run at a lower wattage.  Based on this new information, looks like I am going to set up some programming to turn the cable on/off based on weather conditions.

I like @Neo1738 suggestions above, but since my cables are in downspouts, it requires some additional programming.  The main culprit with the downspouts freezing is when the temperature spikes above 32 during the winter months.  This causes the existing snow on the roof to melt and then freeze (usually in the downspout) once the temperature goes back below 32.  Any suggestions on an additional line of programming to address this?

[RAV]

Variable LastNightBelow35
When outside temp changes, if below 35 set LastNightBelow35 to true, else set to false

When you check to turn off the cable....
If LastNightBelow35 is true, stop.

Once the overnight is high enough, cable will turn off

[ajd123]

On 1/7/2025 at 9:57 AM, RAV said:

Variable LastNightBelow35
When outside temp changes, if below 35 set LastNightBelow35 to true, else set to false

When you check to turn off the cable....
If LastNightBelow35 is true, stop.

Once the overnight is high enough, cable will turn off

Thanks @RAV

When the Timer expires (23:59:59 timer), I have it set to turn off the snow melt circuit.

When the Timer is started, reset or resumed I have it turn on the snow melt circuit.

Does this look correct? 

[ajd123]

My programming above is flawed.  Trying some new programming.  Will post when complete for opinions.

[ajd123]

I figured this out, this was the correct way.

[ajd123]

People on this forum might find this interesting.  I was struggling with this programming so I decided to ask ChatGTP for a hand.  It actually solved this for me.

ChatGPT.pdf

[msgreenf]

wow! pretty sweet! Great idea