994i & Climate Module, writing for Snow-Melt system

[CPUjohn]

Good Morning,

 

I see that most of you are using the climate system to set lighting levels or to water your lawns/crops.  I have a different need....

 

I know it's August, and no one really wants to think about snow right now, but I figured I would get a head start on this project to get those whom work on these kinds of issues to include it for this winter !

 

I just upgraded my 99i to 994i and installed the new climate module, and have some questions about how to program for upcoming weather events.

 

I have a snow-melt system in my driveway, and heater tape around a pipe that extends 100' underground to defrost through-out the cold seasons.  This pipe must be defrosted as it is part of a back-washing filtration system, as well as our laundry,  For the pipe, we have been simply running a pipe-heater Insteon scene based upon local temperature and also whether the snow-melt system is on.

 

But for the snow-melt in my driveway, I would like to create a more sophisticated program as it takes 2-3 hours prior to a snow-fall to heat up the driveway and walkways sufficiently, depending on how cold it is outside. 

 

Typical criteria:   Temperature between 10 and 35 degrees Fahrenheit (below 10, and it's too cold for the system to work, and usually too cold for snow). What I don't see anywhere is an actual snow-falling/precipitation  event, so possibly I could use the "previous 24hour snow-fall total" stored into a variable (i.e. if the snow was predicted to be greater than  0.1").  I was also hoping to see a climate field that indicates actual precipitation.  Its been a long time since I was in science class, and not being a meteorologist, I could use some assistance in understand if the barometric "pressure" field could also be used as a predictor of a snow event.  There are many fields in the climate app, but very few indicate a change, just true/false or fixed numbers !  It appears I have to write programs to store and refresh the numbers, and calculate whether they are going up or down.  Any ideas you may have, as to what combinations of fields you think would be a good place to start.

 

Is there support from HamWeather anywhere ?

 

What we did last season was manually (from cell phones) turn on system based upon weather predictions, and IP cameras visual confirmation, but that was not always sufficient (usually resulting in starting the system too soon or more often, too late).

 

Thank you for any help you can offer.

 

Sincerely,

 

John

Fox Lake, IL

 

[wrj0]

Years ago 'burakk' posted a program "It may snow."  http://forum.universal-devices.com/topic/1793-weather-module/?do=findComment&comment=14248

Based on that post, the following has worked fairly well as a snow predictor for my system located in central NC.

If
        Module 'Climate' Dew Point < 32 °F
    And Module 'Climate' Humidity > 80 %
    And Module 'Climate' Temperature <= 40 °F
 
Then
        Run Program 'Snow Probable' (Then Path)
 
Else
   - No Actions - (To add one, press 'Action')

The program 'Snow Probable' provides message notifications

[johnnyt]

I'm interested in this as well to activate a heated mat and roof cable, Ideally it would report a "it's snowing now" state, which admittedly is probably too much to ask for. I was thinking I might need a personal weather station with a rain gauge and heater to melt snow but can that info get back to ISY? How quickly?

[Michel Kohanim]

Hi johnnyt,

 

Are you looking for something like irrigation module but instead of calculating irrigation requirement it would calculate snow-melt requirement?

 

With kind regards,

Michel

[johnnyt]

Hi johnnyt,

 

Are you looking for something like irrigation module but instead of calculating irrigation requirement it would calculate snow-melt requirement?

 

With kind regards,

Michel

hmm, not sure. If you mean being able to know how much snow has fallen, yes that would be part of it. While I was more asking to have a way to automatically turn on my roof cable and heated mat, it would also be interesting if there was a way to automatically turn them off when the snow stopped.

[larryllix]

I was going to install a driveway snow melt system in my new house. After researching this field I discovered I couldn't afford it. I had a smaller system inplace in my porch slab but the concrete guy put the pipes (yes in my absence) too close to the edge and I punctured one with railing installation.

 

Snow melt systems typically need the snow melt sensor to work properly. The snow not only needs to be melted but completely dried up or you have a sheet of ice when the heat shuts off, making things worse. Perhaps in a milder climate zone where only small amounts of snow  come to be annoying?

 

I don't know how you could replace a snow-melt sensor with a logically designed timer and not just "over-time" the heat causing more energy consumption or having to visully inspect the result every hour.

 

Good luck with it though.

[johnnyt]

Hi johnnyt,

 

Are you looking for something like irrigation module but instead of calculating irrigation requirement it would calculate snow-melt requirement?

 

With kind regards,

Michel

hi Michel, I looked up the irrigation module on the wiki as I knew little about it and think what I would rather is the ability for ISY to get data directly from a PWS rain gauge. Ideally it would have the feel of a subscription service - or maybe something could be done with an Autelis device that listens to the PWS data stream and populates ISY variables - although I realize that's perhaps a bit of a stretch and not under UDI control.

 

 

Sent from my iPad using Tapatalk

[jeffpdavis1]

I have had a snow sensor in my system for a couple of years that just determines if there is snow on the ground at a point in time initially to turn on my roof and gutter heaters in order to prevent ice dams.  While it did that fine, I found I needed to use IP cameras to visually inspect the roof to turn it off appropriately without using too much energy.  The snow sensor itself was just the Photoelectric Sensor E931-S35RR paired with an I/O Linc and mounted vertically on a fence post near the house. When the bottom reflector was covered up enough, it closed the I/O Linc and vice/versa. In the beginning I wanted to mount it on the roof or actually in the gutter but settled for a place that was close by, easy to maintain and paralleled the behavior.  It works reasonably well for turning on the roof heaters but getting the algorithm for turning the heaters off usually resulted in having them on for a day or two too long.

 

This year I've installed the rain water collector heater (for melting snow) on my Davis Instruments Vantage Pro weather station. I will use the snow sensor to turn on/off the heater on the collector so that in times of heavy snow and wind, the collector is able to keep up, hopefully. We live at 8400 feet in Colorado. I suspect that even though, again the sensor is on a fence post 12 feet away from the weather station, there's going to be some tweaking of the heater power, although I should be able to use the Total Rain staying constant for some period of time.  It'd be nice to have the Rain Rate reported to the ISY too, since it certainly is sent off the PWS.

 

Your application could work with this provided the sensor were mounted in that position that most closely mimicked your driveway's snow state.  Once the snow sensor stopped sensing snow, you could turn to some other means, time or outside temp, to find the optimal point to shut it down.  Your biggest problem is that your driveway heater needs to be melting the snow where the snow is being sensed.  You would know best about how to rig that, perhaps mounting the sensors horizontally in some key place where you don't drive, but you do heat.  

 

Your need to turn the system on a couple of hours before the snow was one of mine too so I think you could use the snow predictor program from burakk above for that. 

 

This whole snow sensing idea has resulted in much writing/rewriting. Up until a month ago, I was only using the snow sensor to send me alerts when it was snowing enough to cover the snow sensor (wind and snow required some special attention to avoid alert overload) so that I could choose manually to inspect the roof via cameras and manually turn the heaters on or off.  This was only because the weather conditions were so variable around the time when the snow sensor got cleared that too much energy was wasted in leaving the heaters on too long.  It may be also I just haven't spent enough time with it.  This year, using the snow sensor to turn the rain collector heater on/off should be much more straight forward, that is once Hamweather gets all the PWS weather stations showing up in my climate module. Mine shows up as a CWOP station but the data is unreliable, but that's another thread.

 

 

[jratliff]

I am putting in a pex tubing radiant heat snow melt system in my driveway and front walk this month too. I'm trying to plan out controls and any sensors I need to embed in the concrete. Anyone else controlling their snow melt system with the ISY?

 

I was really hoping to find a nice snow sensor that I could just hook up to an io linc but as far as I can tell the ones I've seen so far look like they're probably some type of resistance signal that is interpreted by the control unit they want you to buy which is also pretty expensive. I don't mind paying if I know its' a good one but I don't see a lot of reviews out there either. The company selling me my system only sells manual control with a slab temperature setpoint to idle when it's up to temp and said their experience was that the automatic sensors have too many false starts. My thought was to write a program in ISY to alert me by text any time the sensor detects snow then I can confirm it. Then I could incorporate the "snow probable" program mentioned above and have the system turn on automatically if the snow sensor is triggered in the middle of the night so I don't miss a notification and wake up to a covered driveway...

 

I like your Photoelectric Sensor idea Jeff, I may incorporate that. But if anyone has any other updated experience please share! Thanks.

[CPUjohn]

It's been a couple of years, and aside from manual remote activation, climate module:condition: snow, alert messages and IP cameras, I am no closer to finding a solution to automating my snow-melt system than when I installed it !

I do have a wonderful track record with the system I designed & built completely clearing all snow on both driveways and walkways.

[502ss]

its funny reading this because i am dealing with the same challenge.  I finally added insteon controllers to my heat tape on my roof. I use a fairly accurate weather station that is only 3 miles from me to tell me when it is snowing, icing, etc. and based on that info I am able to pretty reliably turn on and off the heat tape. I also add small waits to allow for some flexibility.

 

My program to turn on the tape looks like this:

 

 

If

        Module 'Climate' Temperature <= 33 °F

    And (

             Module 'Climate' Condition is Blowing snow

          Or Module 'Climate' Condition is Ice pellets/sleet

          Or Module 'Climate' Condition is Drizzle

          Or Module 'Climate' Condition is Rain

          Or Module 'Climate' Condition is Rain showers

          Or Module 'Climate' Condition is Rain/snow mix

          Or Module 'Climate' Condition is Snow/sleet mix

          Or Module 'Climate' Condition is Wintry mix

          Or Module 'Climate' Condition is Snow

          Or Module 'Climate' Condition is Snow showers

          Or Module 'Climate' Condition is Freezing drizzle

          Or Module 'Climate' Condition is Freezing rain

          Or Module 'Climate' Condition is Freezing spray

        )

 

Then

        Wait  30 minutes 

        Set 'Heat-Tape / Heat-Tape-Back' On

        Wait  5 seconds

        Set 'Heat-Tape / Heat-Tape-Front' On

        Wait  5 seconds

        Set 'Heat-Tape / Heat-Tape-Side' On

        Wait  5 seconds

        Send Notification to 'Jim-text' content 'weather-condition2'

        Send Notification to 'Jim-text' content 'weather-condition'

 

Else

        Run Program 'weather-turns-off-heat-tape' (If)

[Teena]

 

its funny reading this because i am dealing with the same challenge.  I finally added insteon controllers to my heat tape on my roof. I use a fairly accurate weather station that is only 3 miles from me to tell me when it is snowing, icing, etc. and based on that info I am able to pretty reliably turn on and off the heat tape. I also add small waits to allow for some flexibility.

 

My program to turn on the tape looks like this:

 

 

If

        Module 'Climate' Temperature <= 33 °F

    And (

             Module 'Climate' Condition is Blowing snow

          Or Module 'Climate' Condition is Ice pellets/sleet

          Or Module 'Climate' Condition is Drizzle

          Or Module 'Climate' Condition is Rain

          Or Module 'Climate' Condition is Rain showers

          Or Module 'Climate' Condition is Rain/snow mix

          Or Module 'Climate' Condition is Snow/sleet mix

          Or Module 'Climate' Condition is Wintry mix

          Or Module 'Climate' Condition is Snow

          Or Module 'Climate' Condition is Snow showers

          Or Module 'Climate' Condition is Freezing drizzle

          Or Module 'Climate' Condition is Freezing rain

          Or Module 'Climate' Condition is Freezing spray

        )

 

Then

        Wait  30 minutes 

        Set 'Heat-Tape / Heat-Tape-Back' On

        Wait  5 seconds

        Set 'Heat-Tape / Heat-Tape-Front' On

        Wait  5 seconds

        Set 'Heat-Tape / Heat-Tape-Side' On

        Wait  5 seconds

        Send Notification to 'Jim-text' content 'weather-condition2'

        Send Notification to 'Jim-text' content 'weather-condition'

 

Else

        Run Program 'weather-turns-off-heat-tape' (If)

 

 

QUESTION:  How would you write the instructions to turn the tapes OFF??  I have a similar set up and live in the NorthEast (NYC-area) . Like you describe, my weather station is also very close by and gives me accurate info.  

 

I set up a similar set of commands to turn my snow-melt heat tapes ON.  But I didn't want to use the "ELSE" to turn the tapes off, because I do NOT want the tapes to shut off immediately when the conditions are no longer true, ie, as soon as the snow stops.  I want the tapes to stay on for an additional 12 hours after it stops snowing to make sure all the accumulated snow has melted. 

 

Ideally, I'd like to have some commands that say "if the heat tapes are currently on, but it's no longer snowing anymore, and there's no snow in the forecast, then turn the tapes off in 12 hrs".  But if I add a "wait 12 hrs" to a THEN or ELSE statement, then every 5 or 10 min, when it polls the weather station, it will start a new 12hr countdown.  I feel that that is asking for trouble.

 

Ideas anyone????  Many thanks.

[KeviNH]

Something like:

If 
     Time is Last Run time Heat-Tape-On + 12 hours 
    And (
             'Heat-Tape / Heat-Tape-Back'  is On
          Or 'Heat-Tape / Heat-Tape-Front'  is On
          Or 'Heat-Tape / Heat-Tape-Side'  is On
          )
Then
        Set 'Heat-Tape / Heat-Tape-Back' Off
        Set 'Heat-Tape / Heat-Tape-Front' Off
        Set 'Heat-Tape / Heat-Tape-Side' Off

Personally, I use a variable $s.Heat_Tape_Needed, set it to 1 while weather conditions warrant their use.