Page 1 of 2 12 LastLast
Results 1 to 20 of 21

Thread: IoT gauges

  1. #1
    Join Date
    Jul 2018
    Location
    Central Florida
    Posts
    21
    Post Likes

    IoT gauges

    I made my own always-on A/C monitoring system which reports the PT's to the cloud where I can go view graphs from all time.

    Here is the setup from bottom up
    DS18S20 temp sensor & refrigeration tape
    0-5V, 0-500 psi pressure transducer, Digikey
    Custom PCB
    ESP8266
    NodeMCU LUA code
    Thingspeak.com

    All A/C's should send their information to the cloud. A system like this either factory installed or service company installed would be great. We could sell monitoring for a $2/mo fee and predict when the system will need servicing. The Internet service would (on the tech's end) detect certain problems before they are major in a way that only an always-on system could: tiny leaks, TX valve sticking, partial clogs, minor compressor wear. Then reach out to the home owner and offer service as a reduced cost for them to avoid major service.

  2. #2
    Join Date
    Dec 2012
    Location
    columbus, OH
    Posts
    7,049
    Post Likes
    Cool, got pics?


    Sent from my iPhone using Tapatalk

  3. #3
    Join Date
    Nov 2011
    Location
    CO
    Posts
    9,748
    Post Likes
    I know a company that was developing this exact system....checked in to the home base, messaged contractor and or homeowner with problems, etc. etc. they got half through the development stage and the Money backed out. shame really, they could have made millions with it.

  4. #4
    Join Date
    Oct 2018
    Location
    Washington
    Posts
    5
    Post Likes
    Yeah...it is very interesting to look at it...are there any pics?

  5. #5
    Join Date
    Oct 2011
    Location
    Chicagoland Area
    Posts
    13,482
    Post Likes
    Why reinvent the wheel?
    Pelican Wireless and Honeywell LCBS and Prolon are already doing it on the commercial end with temperature and energy data going to the cloud. While they don't monitor pressures you could use a pressure switch wired in to a set of dry contacts that would trigger an alarm which then could be emailed or texted to the service company and/or homeowner. Pelican is the most user friendly of the 3
    Officially, Down for the count

    YOU HAVE TO GET OFF YOUR ASS TO GET ON YOUR FEET

    I know enough to know, I don't know enough
    Why is it that those who complain the most contribute the least?
    MONEY CAN'T BUY HAPPINESS. POVERTY CAN'T BUY ANYTHING

  6. #6
    weber's Avatar
    weber is offline Professional Member/Membership Committee
    Join Date
    Jul 2006
    Location
    Southern Ca, Elkton Md
    Posts
    7,656
    Post Likes
    In the 90's we had this product that would tie into your phone line, in the mid 2000's we developed one that connects to wifi. Today I have a cell based monitoring system. Pressures, temps, amps, SH & SC, flood protection, water usage, and a predictive breakdown algorithm. Along with much more.

    If you're interested in learning more about the product or how to incorporate it into your business model let me know.
    "Correct Installation is the Key"

    .1 has killed more HX then Rush Limbaugh

    What is your TESP?

  7. #7
    Join Date
    Jul 2019
    Location
    Northern Utah
    Posts
    2
    Post Likes

    Sure, I'm interested.

    Quote Originally Posted by weber View Post
    In the 90's we had this product that would tie into your phone line, in the mid 2000's we developed one that connects to wifi. Today I have a cell based monitoring system. Pressures, temps, amps, SH & SC, flood protection, water usage, and a predictive breakdown algorithm. Along with much more.

    If you're interested in learning more about the product or how to incorporate it into your business model let me know.
    Pitch away. Seems like a very cool way to go. Message me.

  8. #8
    Join Date
    Oct 2008
    Location
    Toronto
    Posts
    16
    Post Likes
    I am quite interested. Please send me more info.

  9. #9
    Join Date
    Feb 2013
    Location
    In a house with windows and doors on it.
    Posts
    282
    Post Likes
    Did this ever go anywhere?

  10. #10
    Join Date
    Sep 2020
    Posts
    13
    Post Likes
    Quote Originally Posted by ahanktcd View Post
    I made my own always-on A/C monitoring system which reports the PT's to the cloud where I can go view graphs from all time.

    Here is the setup from bottom up
    DS18S20 temp sensor & refrigeration tape
    0-5V, 0-500 psi pressure transducer, Digikey
    Custom PCB
    ESP8266
    NodeMCU LUA code
    Thingspeak.com

    All A/C's should send their information to the cloud. A system like this either factory installed or service company installed would be great. We could sell monitoring for a $2/mo fee and predict when the system will need servicing. The Internet service would (on the tech's end) detect certain problems before they are major in a way that only an always-on system could: tiny leaks, TX valve sticking, partial clogs, minor compressor wear. Then reach out to the home owner and offer service as a reduced cost for them to avoid major service.
    A very practical idea indeed! Have you been able to implement it on a production scale?

  11. #11
    Join Date
    Sep 2020
    Posts
    13
    Post Likes
    Of course, it's hard to start something new during a pandemic!

  12. #12
    Join Date
    Feb 2007
    Location
    Corpus Christi, TX
    Posts
    1,784
    Post Likes
    https://imanifold.com/pulse/

    I havent used it, but they have rolled out a system, that is $700, and $9/mth the numbers are loaded in your dashboard for monitoring and alerts are sent to your phone/email.
    Testing....Signature on Full Site Forum

  13. #13
    Join Date
    Apr 2006
    Location
    Tyler, Tx
    Posts
    1,371
    Post Likes
    Philippians 4:13
    I can do all things in him that strengthen me.
    Apostle Paul inspired by GOD.

  14. #14
    Join Date
    Jul 2020
    Location
    Tampa, FL
    Posts
    42
    Post Likes
    I made a similar monitoring system to the original described above.

    My system uses [2] ESP8266 Wemos D1 mini modules programmed using the Arduino IDE. One is located near the electrical panel and it monitors condensing unit current and outside temperature near the condensing unit. [It also monitors whole-house electrical consumption which I also like to keep records on.]

    The other is located near the air handler and it monitors return duct temperature, return duct relative humidity, and supply duct temperature. These functions could have also been performed by the first module, but I didn't want to run wires from the sensors near the air handler all the way back to the electrical panel since there was no easy or clean way to do this, and these wifi modules are very inexpensive.

    Both modules are connected to a wifi network so they can communicate with each other as well as the outside world.

    The first module performs the following functions

    - computes cooling degree days based on 30-min outside temp readings near the condensing unit

    - records number of run cycles each day

    - records duration of each run cycle

    - records each run cycle outside temperature

    - records each run cycle condensing unit current draw

    - records each run cycle duct temperatures and humidity level [queries the second module via wifi for this data near the end of each running cycle]

    Each day at 11:59 PM the first module sends me an email with all the above data which I can then add to a spreadsheet.

    Both modules include a web server which can be accessed at any time over the wifi network using any web browser to get current and stored data for the current day in real time.

    This data allows me to monitor duct delta-T vs RH for system performance, and condensing unit current vs outside temperature as well as cycle duration, frequency, and total daily running time vs degree days as basic indicators of proper refrigerant charge level and system performance.

    Condensing unit refrigerant pressures and line temps could also be monitored to calculate SC and SH, but I figured the above was adequate to keep tabs on the performance and health of the system.

    Let me know if anyone has questions or would like additional information, or if you have any ideas on how to improve the system.

    Example of real time web server data report.

    Name:  hvac_mon.jpg
Views: 536
Size:  191.2 KB

  15. #15
    Join Date
    Aug 2020
    Posts
    14
    Post Likes
    Thanks for the detailed review!!!

  16. #16
    Join Date
    Apr 2007
    Location
    Amarillo by mornin'
    Posts
    1,065
    Post Likes
    I have wanted to add superheat and subcool readings for my units at the house. I already monitor compressor amps, fan status, and shut down on over amping. I was going to add transducers to monitor pressures, but when I look at the pressure/temp for the r-410 chart, the readings are not linear.

    So, two things what is the mathematical equation to get SH/SC and where is the best place to put the suction and discharge temp sensors? At the CU or where the lines go into the evap coil?

    Name:  cond_units_house.PNG
Views: 115
Size:  165.0 KB
    "It's not that I'm smart, it's that I stay with the problem longer”
    Albert Einstein

  17. #17
    Join Date
    Jul 2009
    Location
    Kansas
    Posts
    511
    Post Likes
    There is going to be two different formulas for r410a. One for Dew Point and one for Bubble Point. SH = Line Temp - Sat Temp (Dew). and SC = Sat Temp (Bubble) - Line Temp. This PDF has some formulas if you can figure them out for both bubble and dew point. https://www.cantas.com/urunpdf/20.09...mo_prop_si.pdf Depending on what you are using another option is to create an array with a known data set from a PT chart and use that to convert pressure to sat temps.

  18. #18
    Join Date
    Jul 2020
    Location
    Tampa, FL
    Posts
    42
    Post Likes
    Quote Originally Posted by Greend88 View Post
    Depending on what you are using another option is to create an array with a known data set from a PT chart and use that to convert pressure to sat temps.
    That is exactly how I would do it.

  19. Likes psmilligan1 liked this post.
  20. #19
    Join Date
    Jun 2010
    Location
    Plano TX
    Posts
    1
    Post Likes

    IoT Gauges

    I also want to install pressure transducers at my 410A condenser and interface them to an Arduino. I can handle the Arduino/software side but I am not sure what transducers to use. I’ve been researching 0-500 psi transducers with 3-wire interface (pwr, gnd, and 0-5v signal output). Also, I would prefer to attach them to the service ports so I don’t have to open up the system and braze them in. Can anybody recommend a good quality reasonably priced one? BTW I would also use a hard coded s/w table for the pressure temperature lookup.

  21. #20
    Join Date
    Mar 2007
    Location
    On a bull named Foo Manchu
    Posts
    17,452
    Post Likes

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •