The Accurite Therm/Hydgro Mod

O.K. everybody, I knew there had to be a way to make this cheap Thermo/Hygro better. Then a friend of mine gave me the motivation to do it. I gave him my word that I would do it first thing in the morning, and I did, it just took a little while with the pictures and all.

Problem with this thing was that it had to be in the enclosure to measure both the temps (In/Out) and the humidity (%). My friend told me that this was no good and I should find a solution. So not only did I do that, but I decided to share this cheap mod with all of you as well.

Here is what you will need...Soldering Iron (15w) and solder, Razor blade, Two small screw drivers and a pair of small pliers (mine were Craftsman).
http://i217.photobucket.com/albums/c...ccurite001.jpg

Start by taking the back case of of the Accurite.
Notice how the sensor at the end of the wire looks just like the on on the circuit board, they are even marked in/out.
http://i217.photobucket.com/albums/c...ccurite009.jpg

So now, unsolder the wire from the circuit board.
http://i217.photobucket.com/albums/c...ccurite002.jpg

Then unsolder the Hygrometer sensor and the other Temperature sensor.
http://i217.photobucket.com/albums/c...ccurite011.jpg

Figure out what lengths of wire you will need to run and cut the original wire to the appropriate lengths. Strip about 1/8" of wire covering off and solder the section with the original sensor back to the out on the circuit board. In my previous picture you can see I already did this.
http://i217.photobucket.com/albums/c...ccurite002.jpg

Next, solder the other sensors to the other wire sections after stripping and then solder the corresponding wire (make sure to put the temp in the temp spot and same for the hygro) to the circuit board.
http://i217.photobucket.com/albums/c...ccurite004.jpg

Use hot glue on the end of the temp sensor to keep the wires from touching. You will see how they did this from the factory, when you take it out of the plastic part that says SENSOR.
http://i217.photobucket.com/albums/c...ccurite006.jpg

Pass the wires through the back and Hot glue them in place after reattaching the back cover.
http://i217.photobucket.com/albums/c...ccurite003.jpg

When you are finished, you will have three external sensors, 2 for temp and 1 for humidity. It will look something like this. Then you can measure temps for warm side and cool side as well as Humidity with the unit mounted outside of the enclosure.
http://i217.photobucket.com/albums/c...ccurite007.jpg

I hope this pictorial can shed some light on how to do this simple mod, it should be a sticky as it will reduce the amount of money we all have to spend on temp/hygro sensors. But most importantly, it will prevent our Herps from coming into contact with the equipment we use and potential hazards they pose.
http://i217.photobucket.com/albums/c...curite/003.jpg


I would like to give special thanks to Will Bird from Extraordinary Ectotherms - Ectotherms.net - Home
He is the person that gave me the motivation to do this today.

Very good! Thanks :). What size wire?

Very very nice *cough* sticky *cough*

I am fine just taking failed Acurite brand units back to Wal-Mart, they take anything back! I have a handful of packages I save for this reason:D

But YOU my friend have done an AWESOME job on this modification.

Job well done:gj:

Wow,

Now that is an exceptionally good idea. :bow: :bow:

Is the size of the temp probes small enough that you could use something cheap and disposable like the plastic top and bottom caps from a common pen to once again make them totally waterproof ( well ok splashproof ) like the original outside probe?

Would the humidity probe fit in the cap from a large marker?

You would probably have to put either a fine mesh or a few small saw cuts (with a dremmel or similar ) to allow the air flow to keep it working but it would give it a little more protection.

Or do you find it doesn't need anything like that when in use?

**edit**

Do you think the humidity probe would work without problems in an incubator or egg tub?

**end edit**


dr del

I gave that some thought as I was figuring out how I was going to do this. I stopped by a dollar store looking for something smooth, low profile and easily modified. That's when I found these.
http://i217.photobucket.com/albums/c...curite/006.jpg

As for the wire, although I got a cheap 20ft section of 26 gauge speaker wire from the dollar store, I was able to just use the original wire that came with the unit (my enclosure is not real big). It would probably work the same for a rack system too.

FWIW the sensors are all waterproof. The big thing is to use hot glue to seal the exposed wire preventing any possibility of a short.

Great info. I have a few old ones to practice on:gj:

This is awesome and should be a stickey! Too bad I didn't know about this 2 hours ago when I was just finishing one of my tub setups!

Hi,

But how does the humidity sensor work if you totally seal it?

I thought it needed air exchange. :confused:

Good call on the googly eyes though. :D


dr del

Actually you are right, the Hygrometer sensor cannot be sealed. Only the temp sensors can be sealed, sorry, I should have been a bit clearer earlier. The googly eyes will get the Dremel treatment for the hygrometer sensor to provide proper airflow.

We have a plethora of stickies in this forum already...but this one is so brilliant and unique that I just had to add one more! Excellent job!! :gj:

Have you tested it to make sure the reading is correct?

Yup. Used 4% silver solder to make sure the resistance didn't get out of whack too. Both remote temperature sensors are within 0.1 (not female :rofl:) degrees of each other, which is as good as stock.

Very innovative!! I just *love* seeing reptile keepers "think outside the sweater box" when it comes to functional husbandry practices/tools. :)

It came out much nicer and doesn't look like a hack job. Here are the updated pics and some tips to make it go smoother for you guys.

BTW it only takes 1/2hr to do this mod, I took my time and timed it.

It is alot easier to make the connections if you "Tin" the ends of the wires first.
http://i217.photobucket.com/albums/c...curite/012.jpg

Simply apply heat and apply solder at the same time and you will get this.
http://i217.photobucket.com/albums/c...curite/014.jpg

It makes the connections look much better as well.
http://i217.photobucket.com/albums/c...curite/011.jpg

Then instead if running them out the vent in the back like I did with the first one, I used my cordless drill to enlarge the original hole. Then ran all the wires out through it like this.
http://i217.photobucket.com/albums/c...curite/016.jpg

It ended up looking much better than the first one I did.
http://i217.photobucket.com/albums/c...curite/015.jpg

Enjoy :gj:

Pretty spiffy stuff man! Thanks alot.

thanks for this diy tut! wouldn't have thought of this one lol. successfully modded the thermo/hygrometer and tested it. works great :)

thanks again!
Nigel:gj:

-edit-
also, for those of you that haven't done this yet...DON'T USE RESIN CORE SOLDER!! it's doable...but it was wayyyyyyy too much of a hassle. took 3x longer than needed lol!

Yeah :rofl: silver solder is best for circuits.

Glad to hear someone else tried it though :gj:

Wow dude! Great job!

Haha, that is an awesome idea you have!

I wish I knew how to do any of that stuff you mentioned or I would!

You should sell them pre-modified ;) And sell me one! LOL

I agree, with above. You should sell them with like $5 markup. Your Design and expertise is worth that!!

Pete:salute:

Great job on explaining it but could you post a pic or 2 with what you did to the googly eyes. I have a pretty good idea... :gj:

Quote:

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Originally Posted by BeastMaster

http://i217.photobucket.com/albums/c...curite/003.jpg

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WOW that is a GORGEOUS setup

Great thread, thanks for posting this.

I did the mod to 1 of my Accurites last night. The temperature sensors are tracking really well to the un-modified Accurite but the humidity is off (low) by about 10% right now and was tracking high last night.

Anyone else who did the mod have the same problems? I haven't "protected" the modified Accurite's humidity sensor yet so is it just a function of "contained" versus "open"? I did touch the surface of the sensor when doing the project. Would that have caused inherent problems? Do I now need to clean the sensor?

Thanks in advance for any replies.

I just don't understand why you need to disconnect the out wire just to reconnect it again!

Hi,

Quote:

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Originally Posted by seeya205

I just don't understand why you need to disconnect the out wire just to reconnect it again!

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It's because he is using the original probe wire cut into three sections - removing it and cutting from the soldered end lets you put each original component back in the same place in regards to the circuit.

Probably not a big deal all in all but it's neater. :P


dr del

It does make it neater if you use that wire for all three components. It was relatively easy to do even for a amateur like me. I'm still wondering if anyone else out there had the same troubles with the humidity sensor not being calibrated after this mod. My sensor is reading between 20-25% lower than an unmodified unit.

Anyone else experience this?

I actually had a problem un-soldering the IN sensor. I ended up having to purchase another unit because it seems that the sensor broke off, and came apart. It was almost like the sensor was not just soldered on...but yet the wires actually went down in the unit itself. I was just checking to see if there was anyone else that had this particular problem, or was it a result of my poor handy skills....which are not bad btw.

Thanks for any advice. I'm just kinda skeptical of trying it again now lol.

Thanks for this awesome DIY.

I tried this today, having never really soldered before, and while I get readings on my Accurite, they're definitely not accurate. One temp reads around 42F, and I know it's at least 68F in the house right now. The other reads just "HI . F". Both sensors are sitting right next to each other. The humidity is probably right, but my guess is I killed the circuits for the temps when I was trying to de-solder the existing connections. It just took too long and I think I must have applied too much heat. Should I be trying to suck out the old solder with a solder bulb, or just heat it up and pull the connection off?

Now that I've done one, the next will probably be easier and may actually work, but I think one will be the practice mod...

OK, first, if you touch the hygro, it needs to be cleaned with alcohol (no, not beer :8: ) and if your readings are off, it's because you probably had a low wattage (low wattage does not mean cheap) soldering iron and cooked something.

Most circuit soldering is done with higher wattage's because you have very little surface touch time. This means that after a second or so, the heat will start to do microscopic damage to the circuits and the sensors. Radio Shack sells an item that is made off aluminum and looks like a little clothes pin. It is called a heat sync and will prevent the heat from reaching the sensor. I did not have this item at my disposal when I undertook this project though. But if you have not done a lot of soldering, it may help a little bit. They also have the second pair of hands you always wish you had when doing wierd projects. It's the goofy looking cloths pin clamp and magnifying glass thingy they have in the soldering section for $20.

I would like to see some pics of the ones you guys have done. Maybe I will learn something new to do with my next one.......

Great write up. Tried it today and it came out great. Perfect for my viper setup where i don't want to go in all the time to check temps.

Im goint to have to do these to all mi accurites! thanks

I did it and it works great! Just make sure you follow Beastmasters advise and use a 15watt soldering iron or other wise you could mess up the circuit board.

I just tried it. It was only my second time ever soldering, and I have it working perfectly, right now I've just shortened the 10' wire to 3' for the external sensor. Tomorrow I plan on tackling the insides properly
:)

Quote:

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Originally Posted by WakoNako

I just tried it. It was only my second time ever soldering, and I have it working perfectly, right now I've just shortened the 10' wire to 3' for the external sensor. Tomorrow I plan on tackling the insides properly
:)

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IT WORKS!!!!!
lol, I just finished it. I was scared I had burn the board at first but Its now sat waiting a protective container for the humidity sensor and both temp readouts are exactly the same.
I can't test if humidity is working perfectly, but right now its hovering around 50% in my room (its not going in the enclosure until the sensors are protected) and it feels right.

I'm going out soon so I'm going to get googly eyes like someone stated earlier and try them out.

I'll post a pic when its completely finished.

Just modded my acu rite since i didnt have anything else to do tonight. It's working good i think the humidity is off by 1% tho

Question for those that did it what did u do with ur in sensor and ur humidity sensor? I did hot glue around the wires so nothing touches and shorts out.

Pics if u can :)

I tried the Craft googley eye thing and it didn't work. In the end, I just glued the two sensors above the substrate to the wall of the enclosure.

Quote:

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Originally Posted by WakoNako

I tried the Craft googley eye thing and it didn't work. In the end, I just glued the two sensors above the substrate to the wall of the enclosure.

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+1 :gj:

Well I broke down and gave this one a try…
After reading the post on what to do with the hydro probe and the
googley eyes not working well for this, I decided to try buttons.
Drilled a few extra holes in a couple then only sandwiched
the probe ¾ of the way around with a little hot glue.

https://ball-pythons.net/gallery/fil...6.7.10_015.jpg

https://ball-pythons.net/gallery/fil...6.7.10_012.jpg

https://ball-pythons.net/gallery/fil...6.7.10_014.jpg

just to make sure, the temperature sensors will work ok with a some hot glue around them?:confused::confused:

What if I mimic the original housing with some kind of plastic and give the hygrometer sensor a little OPEN enclosure as well?



Also, I forgot, Are the 'probes' or sensor's legs side oriented? I mean is one + and the other one - (meaning that I'll have to re-wire it with each leg in the terminal that It was originally wired or can I just wire it inverted?

thanks

Just a couple suggestions to anyone doing this mod (btw it is a great one). If you are getting the "Hi F", chances are that you may have a cold solder. That means that it looks like it is soldered but it is not actually making contact. Try undoing the solder joint, and redoing it. Also, the bad temp reading and possibly the same "Hi F" error are due to polarity. Most electrical temp probes are made of two types of wire (they will look the same but are different materials). Without going into why they have two types of wire lets just say the legs of the sensor need to go back in the same hole of the circuit board. I would need to open one up when I get home to see if that is this case. Good chance it is.


If you are worried about wether or not your hygrometer is accurate here is a link to a simple test you can perform at home. It is very similar to how they are calibrated and set up in an industrial setting. BTW, I calibrate laboratory
instruments for a living.

Hygromter Calibration

interesting mod but definitely not for everyone

awesome. i did it with my acurite (its a black one with the indoor/outdoor temp and humidity). I messed up on the first one, but it was broken already anyways and was nothing more than just practice. The second one worked GREAT. For the humidity sensor protective piece, i used an old analog hyrogometer and gutted it, then placed the sensor in there and hot glued it, being sure that i didnt seal it up but was adequately protected. Its working great. Thanks again for this DIY.

Did this mod today. Readings are within a degree of my other new, un-modded unit. Whew! Now I've got two more to do... Thanks for posting this.

i was wondering where everyone was purchasing these from. are they at local stores or are they an internet bought item. sorry if its an obvious answer. ive found some online but they dont seem to be the same product. i didnt know if i could use any of their products and then use the sensors inside and use wire to extend the probes. from what i saw on here there were probes supplied with the product and the wires were remanufactured to suite the needs for the mod. thanks in advance for any help.

Interesting but I just want to point out that adding wire between a resistive sensor and board will change the reistance it is calibrated for and reduce the accuracy more than it was orginally. By how much I can't say it might be next to nothing and it might be quite substancial. The probe digital ones I have are effected by pinching the cord in a hinge, I'd expect a change of some sort. In my experience the accurites are not paticalluraly accurate to start with, I'd be hesitant to mod one.

Quote:

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Originally Posted by mdwagoner

i was wondering where everyone was purchasing these from. are they at local stores or are they an internet bought item.

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You can get the Accurite Therm/Hydro @ Wal-Mart. They have a 'new' design out now that looks a little different than the one he used for the mod. They are about $12.

Did this yesterday and works good I only took the humidity sensor out I just need to work on something to protect it and attach it before i really put it to use. Thank you. I will be working on more of these.

Awesome mod, thanks for the write up.

Quote:

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Originally Posted by kitedemon

Interesting but I just want to point out that adding wire between a resistive sensor and board will change the reistance it is calibrated for and reduce the accuracy more than it was orginally. By how much I can't say it might be next to nothing and it might be quite substancial. The probe digital ones I have are effected by pinching the cord in a hinge, I'd expect a change of some sort. In my experience the accurites are not paticalluraly accurate to start with, I'd be hesitant to mod one.

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If you are talking about "scientific grade" electronics, then I agree with you, it would be easy to throw off the readings with ANY changes to the resistance (solder choice, wire type/length included) of a calibrated sensor. However, these are cheap electronic units ($10-$12) that (as you said) aren't super accurate anyway. They have generic sensors that probably aren't even calibrated to begin with. LOL.

I posted this mod for others as a way to improve the Accurite's functionality without the need to spend a lot of money on fancy "scientific grade" units (most of which cost 2-3 times as much as an Accurite). So bash my mod if you want and by all means, please don't use it. But discouraging remarks about a useful mod (that has already been proven numerous times by other members) on an already cheap piece of equipment, aren't necessary. I'm sure there are plenty of members on here that can't afford, or don't want to spend their money on expensive thermometers etc...

Oh, and I just want to point out that spell check is done by right clicking ;)
(speaking of accuracy :D )