<div dir="ltr">Why bother measuring the temperature of the room? Measure temperatures of the machine if you're concerned about it overheating. If you want to measure air temperature coming into the machine, there's an article here on using a $15 USB thermometer to measure air temperature: <a href="https://grepular.com/Using_Linux_to_Monitor_Room_Temperature_Remotely_and_Cheaply">https://grepular.com/Using_Linux_to_Monitor_Room_Temperature_Remotely_and_Cheaply</a><div>
<br></div><div style>BTW, your thermometers actually seem to be quite good. +/- 1 deg F is very reasonable for measuring room temperature -- in fact, I would be shocked if there was less than 1 degree of variance in the temperature throughout the room. In the room where my always-on computer is, the variance is about 8 degrees from one area to another, so unless the thermometer is placed very carefully, 1 degree is insignificant. What would be more interesting is if a given thermometer is stable, or tends to have readings that float around.</div>
</div><div class="gmail_extra"><br><br><div class="gmail_quote">On Wed, May 29, 2013 at 2:47 PM, Ron Frazier (ALE) <span dir="ltr"><<a href="mailto:atllinuxenthinfo@techstarship.com" target="_blank">atllinuxenthinfo@techstarship.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi all,<br>
<br>
I have a computer in a downstairs room that runs all the time. The processes I have it doing generate lots of heat; and there is no hvac thermostat there. There is a heating / air vent and return though, so it gets some air circulation. I need to monitor the temperature in the room from upstairs.<br>
<br>
I bought an Acurite backyard weather thermometer from home depot with remote sensor. I put batteries in the sensor and display and verified that the sensor is transmitting. I sat both units a foot apart in the living room maybe 12 feed from the honeywell thermostat on the wall. I trust the temperature reading of the honeywell more than any other sensor I have.<br>
<br>
The honeywell says it's 73 in this room. It doesn't show decimals.<br>
My fairly nice Oregon Scientific weather station shows 73.6 in this room.<br>
A cheap Lacross Technology weather monitor that I use to monitor humidity in the basement says 73.9 in this room.<br>
And a cheap Lacross Technology (I think) wall clock shows 73.0 in this room.<br>
<br>
It's actually annoying that all these sensors within 12 feet of each other are so different. I guess I'll assume that the actual temperature is between 73 and 74; and I think it's more toward 73.<br>
<br>
My NEW weather monitor is showing 74 or 75 on both indoor and outdoor temp with both sensors in the same place, which probably about 1-2 degrees high. This one doesn't display decimals.<br>
<br>
In any case, while that's not ultra critical, I'm considering returning it.<br>
<br>
So, I'm looking into other alternatives.<br>
<br>
1) Buy another more expensive weather station, like another Oregon Scientific. That would cost $ 50 - $ 75.<br>
<br>
2) Buy a wifi or lan attached temperature sensor. That way, I could just display the weather sensor's web page from a local 192.168.x.x address and see the temperature in the basement room.<br>
<br>
3) Use a rpi plus a sensor to do the same thing as number 2. Would probably cost more.<br>
<br>
4) Attach a USB temp sensor to the pc downstairs and run a web server on it to display the temperature.<br>
<br>
Other than having a more accurate stand alone unit like the one I bought, I like option 2 best. That way, I could set a web page up in a small window on my monitor upstairs to show the downstairs temperature and set it to auto reload every few minutes. Also, I could run a script on the downstairs computer to poll the sensor periodically and send me an email if the temperature exceeds a preset limit.<br>
<br>
Anyone know what I might use to get this done?<br>
<br>
By the way, when I was researching how to monitor my basement humidity, I found out that any humidity sensor less than about $ 300 is probably rubbish for precision. The tolerance is usually + / - 5%. I think that's ridiculous, but I guess it's hard to do much better for cheap.<br>
<br>
Thanks in advance.<br>
<br>
Sincerely,<br>
<br>
Ron<br>
<br>
<br>
<br>
--<br>
<br>
Sent from my Android Acer A500 tablet with bluetooth keyboard and K-9 Mail.<br>
Please excuse my potential brevity if I'm typing on the touch screen.<br>
<br>
(PS - If you email me and don't get a quick response, you might want to<br>
call on the phone. I get about 300 emails per day from alternate energy<br>
mailing lists and such. I don't always see new email messages very quickly.)<br>
<br>
Ron Frazier<br>
770-205-9422 (O) Leave a message.<br>
linuxdude AT <a href="http://techstarship.com" target="_blank">techstarship.com</a><br>
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<br>
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</blockquote></div><br><br clear="all"><div><br></div>-- <br>David Tomaschik<br>OpenPGP: 0x5DEA789B<br><a href="http://systemoverlord.com" target="_blank">http://systemoverlord.com</a><br><a href="mailto:david@systemoverlord.com" target="_blank">david@systemoverlord.com</a>
</div>