Vote for BP.Net for the 2013 Forum of the Year! Click here for more info.

» Site Navigation

» Home
 > FAQ

» Online Users: 698

0 members and 698 guests
No Members online
Most users ever online was 47,180, 07-16-2025 at 05:30 PM.

» Today's Birthdays

None

» Stats

Members: 75,905
Threads: 249,104
Posts: 2,572,100
Top Poster: JLC (31,651)
Welcome to our newest member, Pattyhud
Page 1 of 2 12 LastLast
Results 1 to 10 of 20
  1. #1
    Registered User mackynz's Avatar
    Join Date
    05-19-2012
    Location
    WI
    Posts
    580
    Thanks
    135
    Thanked 173 Times in 115 Posts

    Thermostat issue, help please

    Bear with me here, this will take a bit of explaining.

    I started out using a Hyrdrofarm thermostat. To get a hot spot of ~90F I had to set it to 80F which makes no sense since if anything it should need to be set higher to offset heat lost. I just chalked it up to being cheap.

    Then I got a Herpstat 2, same issue, 80F gave me a 90F hotspot through the PVC of an AP T8. This threw me, this thermostat is supposed to be accurate to something like .01F why would it need to be 10F lower than it should, was it related to the Hydrofarm having the same problem?

    Now, I cleaned the cage recently and the temps bottomed out completely, I now have the thermostat set to 100F and it is reading 85F in the cage, nothing changed I pulled everything out and put it back in, this was a few days ago.

    Additional details: In both cases the thermostat probe was between the flexwatt and the bottom of the cage. My Accurite thermometer probe is inside the cage under the corrugated wrap. The temp gun I have and the Accurite agree with each other. Nothing has changed in or outside of the cage at all except me putting in new corrugated wrap.

    Last note, the temp under the corrugated wrap reads 90F while the surface reads 85F, before it was even and there should be no way it is losing that much through that little cardboard.

    Thoughts? I'm afraid its going to go back to the way it was while I'm at work and cook my snake.

  2. #2
    BPnet Senior Member kitedemon's Avatar
    Join Date
    01-01-2010
    Location
    NS Canada
    Posts
    6,062
    Thanks
    657
    Thanked 1,795 Times in 1,391 Posts
    Images: 11
    5ºF to a sheet of cardboard sound right to me. The herpstats are accurate to 0.9ºF not 0.01ºF that would be the deal of the century if it were. I would trust the herpstat probe over a accurite (IMO 100% junk +/-4ºF how is that good?) and IR guns.

    You started gaining 10ºF then after changing the substrate you lost 5ºF the only explanation I could think of is there is something else causing the gain (fluorescent lighting can do so)

    If you met to say when set at 90ºF you get 80ºF inside this makes more sense, if the paper is not in direct and full contact with the floor it may not heat fully. The accurite measures the air temp and IR gun the surface I would be suspect if they were exactly the same. Paper is an excellent insulator all that cellulose blown in insulation is a testament to how efficient. It not surprising to lose a a bunch of degrees what are the ambient air temps in the middle of the enclosure? with the light on and off (40min to cool) ? Ambient air temps will have great impact on the loss to the substrate. It is quite possible that the ambient air temps are the culprit in either case (gaining over the T-stat or loosing)
    Last edited by kitedemon; 03-26-2013 at 07:50 PM.

  3. #3
    BPnet Veteran interloc's Avatar
    Join Date
    09-25-2011
    Location
    ontario canada
    Posts
    1,538
    Thanks
    331
    Thanked 627 Times in 410 Posts
    Images: 79

    Thermostat issue, help please

    Is the probe attached to the heat tape in any fashion? I always preferred to tape my probes down. I feel it's more accurate.

  4. The Following User Says Thank You to interloc For This Useful Post:

    Raven01 (03-26-2013)

  5. #4
    BPnet Veteran Raven01's Avatar
    Join Date
    01-29-2013
    Location
    Peterborough, ON
    Posts
    854
    Thanks
    254
    Thanked 332 Times in 233 Posts
    Images: 2

    Re: Thermostat issue, help please

    Quote Originally Posted by interloc View Post
    Is the probe attached to the heat tape in any fashion? I always preferred to tape my probes down. I feel it's more accurate.
    The probes transmit a tiny charge to the main unit, is there anything that could be interfering with this signal? Magnetic field or bundles of other current carrying wires?
    As much as everyone loves Herpstat it isn't inconceivable that one or two faulty units get out of the shop and into circulation. But, what is very improbable is that not only did this happen but, the less expensive unit also exhibited the same issues.
    New units with new probes eliminates broken wires inside the insulation relaying a lower temp than actually measured so, you have me stumped unless there is a placement or interference issue.

  6. #5
    Registered User mackynz's Avatar
    Join Date
    05-19-2012
    Location
    WI
    Posts
    580
    Thanks
    135
    Thanked 173 Times in 115 Posts

    Re: Thermostat issue, help please

    Quote Originally Posted by kitedemon View Post
    5ºF to a sheet of cardboard sound right to me. The herpstats are accurate to 0.9ºF not 0.01ºF that would be the deal of the century if it were. I would trust the herpstat probe over a accurite (IMO 100% junk +/-4ºF how is that good?) and IR guns.
    It's just strange that the temp gun and accurite say the same thing... Plus if the Herpstat was right, when I set it at 80F the temp would be a bit lower than that and I think there would have been some digestion issues.


    Quote Originally Posted by kitedemon View Post
    If you met to say when set at 90ºF you get 80ºF inside this makes more sense
    That would make sense, but it's the opposite, which is why I'm not sure how much I trust the Herpstat....

    Quote Originally Posted by interloc View Post
    Is the probe attached to the heat tape in any fashion? I always preferred to tape my probes down. I feel it's more accurate.
    The thermostat probe is in the little groove they put in the bottom of the AP T8, it's snug between the Flexwatt and bottom of the enclosure.

    Quote Originally Posted by Raven01 View Post
    The probes transmit a tiny charge to the main unit, is there anything that could be interfering with this signal? Magnetic field or bundles of other current carrying wires?
    No electronics nearby to be causing this.


    I just find it strange that the Herpstat and Hydrofarm were off by 10F. And now having to have it set 20F higher than it was before cleaning the cage worries me.


  7. #6
    BPnet Veteran The Serpent Merchant's Avatar
    Join Date
    10-15-2011
    Location
    Orlando, Florida
    Posts
    8,193
    Thanks
    1,504
    Thanked 3,300 Times in 2,344 Posts
    Does the thermostat probe and the power cord for either the herpstat or the heat source? Electrical interference from an AC power cord can easily effect a low voltage DC signal. That could have been the issue with the hydrofarm as well.

    What (if anything) did you use to attach the herpstat's probe in the slot?

    Here is a simple test. move the herpstat's probe inside the cage, and place it right next to the acu-rites probe.

    Something is seriously wrong here. AP cages are made of thick PVC. I have to set my herpstat to 99-102.5 to get a 90 degree hotspot. The fact that 2 separate thermostats had the same issue tells my that they probably aren't the issue. You need to isolate the issue. If you have anything else in or near the cage that produces heat (like the fluorescent lights sold by AP) turn them all off. Something is adding heat to the cages. You could also try unplugging the heat tape for a day or so and see how cold the cage gets.

    Your herpstat hasn't accidentally been adjusted has it? There is a calibration setting in the menus to adjust the probe reading.

    Your current thermostat set temperature actually sounds reasonable. but there is no way a herpstat set to 80 could heat a cage to the proper temperatures.
    ~Aaron

    0.1 Pastel 100% Het Clown Ball Python (Hestia)
    1.0 Coastal/Jungle Carpet Python (Shagrath)
    0.1 Dumeril's Boa (Nergal)

    0.1 Bearded Dragon (Gaius)

    1.0 Siberian Husky (Picard)
    0.1 German Shepherd/Lab Mix (Jadzia)

  8. #7
    BPnet Senior Member kitedemon's Avatar
    Join Date
    01-01-2010
    Location
    NS Canada
    Posts
    6,062
    Thanks
    657
    Thanked 1,795 Times in 1,391 Posts
    Images: 11
    What is the ambient air temp? This is the true controlling factor and key to the whole system. if the air temps are warm the T-stat cannot cool off the enclosure. What is the herpstat reading in power %?

  9. #8
    Registered User mackynz's Avatar
    Join Date
    05-19-2012
    Location
    WI
    Posts
    580
    Thanks
    135
    Thanked 173 Times in 115 Posts

    Re: Thermostat issue, help please

    Quote Originally Posted by The Serpent Merchant View Post
    Does the thermostat probe and the power cord for either the herpstat or the heat source? Electrical interference from an AC power cord can easily effect a low voltage DC signal. That could have been the issue with the hydrofarm as well.

    What (if anything) did you use to attach the herpstat's probe in the slot?

    Here is a simple test. move the herpstat's probe inside the cage, and place it right next to the acu-rites probe.

    Something is seriously wrong here. AP cages are made of thick PVC. I have to set my herpstat to 99-102.5 to get a 90 degree hotspot. The fact that 2 separate thermostats had the same issue tells my that they probably aren't the issue. You need to isolate the issue. If you have anything else in or near the cage that produces heat (like the fluorescent lights sold by AP) turn them all off. Something is adding heat to the cages. You could also try unplugging the heat tape for a day or so and see how cold the cage gets.

    Your herpstat hasn't accidentally been adjusted has it? There is a calibration setting in the menus to adjust the probe reading.

    Your current thermostat set temperature actually sounds reasonable. but there is no way a herpstat set to 80 could heat a cage to the proper temperatures.
    I was hoping you your engineering brain would stop by. The only thing holding the probe in place is the weight of the cage, its sandwiched into the groove, no tape or anything obstructing it. I should add that underneath the cage is a board covered in an insulating foil, it's flush with the cage bottom. I'll isolate the cage from anything else electronic in the room, I'll just unplug everything but the thermostat/heat tape tomorrow night. I'll also try putting the probe in the cage next to the acurite one, but I'll have to do it tomorrow evening because I want to be able to watch the temps closely.

    I also have a calibrated laboratory grade mercury thermometer I can put into the mix (obviously not while my snake is in there).

    And to kitedemon, the ambient is at 77F at time or writing, it was steady at 80-81 before this all started. The drop is likely due to me opening the cage quite a bit today. Also the % is holding around 25-27

    Thanks for all the help and ideas everyone, I'll give it a try tomorrow and report back with what happens.
    Last edited by mackynz; 03-27-2013 at 12:27 AM.

  10. #9
    BPnet Veteran The Serpent Merchant's Avatar
    Join Date
    10-15-2011
    Location
    Orlando, Florida
    Posts
    8,193
    Thanks
    1,504
    Thanked 3,300 Times in 2,344 Posts
    I've been thinking about this for awhile now. I don't think anyone has mentioned the elephant in the room yet. Could it be the flexwatt itself? I know that some strips of flexwatt aren't as consistent as others are. It is possible that your probe is on a "cool" spot of the heat tape, and the majority of the rest of the flexwatt is actually hotter. This would explain why 2 thermostats had the same issue and why your thermometer/temp gun also read the same.
    ~Aaron

    0.1 Pastel 100% Het Clown Ball Python (Hestia)
    1.0 Coastal/Jungle Carpet Python (Shagrath)
    0.1 Dumeril's Boa (Nergal)

    0.1 Bearded Dragon (Gaius)

    1.0 Siberian Husky (Picard)
    0.1 German Shepherd/Lab Mix (Jadzia)

  11. The Following User Says Thank You to The Serpent Merchant For This Useful Post:

    Foschi Exotic Serpents (03-27-2013)

  12. #10
    BPnet Senior Member kitedemon's Avatar
    Join Date
    01-01-2010
    Location
    NS Canada
    Posts
    6,062
    Thanks
    657
    Thanked 1,795 Times in 1,391 Posts
    Images: 11
    The Flex is always a possiability. A second thought is the the probe cable running along the flex power supply? This also could cause odd issues. I have never seen an issue like this. What % does the herpstat read most of the time.

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
  •  
Powered by vBadvanced CMPS v4.2.1