Set your thermostat for C or F degrees?

Xringer · 01-29-12, 05:25 PM

I've posted about this somewhere before, but here it is again! Note the cheat sheet.. C & actual F.

Why would an old Texan, who has used Fahrenheit all his life, start using Celsius??

Not 100% sure, but I think the software in all 2-digit temperature measuring devices, that are switchable between F&C, is based on C, and perform a rough conversion when set to display in F..

Some of these devices (like the IR remote thermostat shown above) increment 1 deg when in C mode,
but in 2 deg when in F mode.. (Meaning a loss of Fahrenheit resolution).

Since my Sanyo remotes are C based, and only displays F setpoint temps
in even numbers, it's very inaccurate around the normal comfort zone..

Here's a little experiment I did.. First, I incremented the setpoint by 1 C, and then switched to F and read out the F setpoint..

C___F
18 64
19 66
20 68
21 70
22 72
23 72
24 74

Don't you just love the conversion of both 22C and 23C to 72F?? Yeah, they rounded up, and then rounded down..
So, I feel it's more accurate just to stick with C.. That way, I'll know which 72, that I'm really using..

MN Renovator · 01-30-12, 02:05 PM

My thermostat has the full F resolution, it doesn't skip any digits or do anything weird with the setpoints as you describe. I think your is doing it because it was likely not designed with us in mind, the US is a bit lonely when it comes to using Fahrenheit. One thing I did just realize though is that my -1/+2 temp range that my thermostat uses could be effectively increased in Celsius instead of Fahrenheit. It is sunny and 49 degrees F right now here so my furnace probably won't run until early morning so I'll have to play with it then.

Edit: Interesting, removing the thermostat and flipping the switch to celcius has no effect. I suppose I'll have to pull the batteries to get the thermostat to recognize that I changed the setting. I'll wait until month-end so I can accurately record the energy data for the month before wiping it.

Piwoslaw · 01-30-12, 02:19 PM

Quote:

Originally Posted by Xringer

Why would an old Texan, who has used Fahrenheit all his life, start using Celsius??

Because the metric system is better? And it took the old Texan all those years to realise that?
Just kiddin'

Xringer · 01-30-12, 03:17 PM

Quote:

Originally Posted by Piwoslaw

Because the metric system is better? And it took the old Texan all those years to realise that?
Just kiddin'

Hey, before all these fancy digital gizmos came along, how did know that
I was really setting my stat to 20C, instead of 68F??

Good idea to introduce new measurement standards.?.
I'm not so sure I like the idea of crashing a Mars mission or running out of fuel,
because the guys at the airport used liters, instead of gallons..

Solar Mike · 01-31-12, 04:58 AM

Reminds me many years ago when NZ was in the throes of switching over from imperial to metric, a certain Govt science laboratory was getting a new lab built, the room length stainless steel bench top came back from the fabricators and didnt fit; its original spec was in feet\inches and the fabricators used metric so this tiny bench top with 10 hand sized sink units arrived much to everyone's amusement except the site manager...

Xringer · 01-31-12, 10:21 AM

Hahaha! That was a Model of the bench top! LOL!!

MN Renovator · 02-01-12, 09:43 AM

I pulled the battery after saving the monthly data and watched it run through a few cycles. Turns out mine runs on the F scale internally and when switched to C it will convert to C on the display but when it cycles it still shows the same temperature and shut off 1 degree above in C when in reality it is still going down 1 degree F, and running until it is 2F above and shutting off. Interesting experiment as it seems be behave opposite of yours. I actually checked the manual and it confirms that it is -1f/+2f and doesn't change when displaying C.

Xringer · 02-01-12, 03:29 PM

Check out the Dallas DS1620.. You divide the temperature output number by two and it's C..
Getting F is somewhat more complex..

01-29-12, 05:25 PM	#1
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	Set your thermostat for C or F degrees? I've posted about this somewhere before, but here it is again! Note the cheat sheet.. C & actual F. Why would an old Texan, who has used Fahrenheit all his life, start using Celsius?? Not 100% sure, but I think the software in all 2-digit temperature measuring devices, that are switchable between F&C, is based on C, and perform a rough conversion when set to display in F.. Some of these devices (like the IR remote thermostat shown above) increment 1 deg when in C mode, but in 2 deg when in F mode.. (Meaning a loss of Fahrenheit resolution). Since my Sanyo remotes are C based, and only displays F setpoint temps in even numbers, it's very inaccurate around the normal comfort zone.. Here's a little experiment I did.. First, I incremented the setpoint by 1 C, and then switched to F and read out the F setpoint.. C___F 18 64 19 66 20 68 21 70 22 72 23 72 24 74 Don't you just love the conversion of both 22C and 23C to 72F?? Yeah, they rounded up, and then rounded down.. So, I feel it's more accurate just to stick with C.. That way, I'll know which 72, that I'm really using.. Attached Thumbnails __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

01-30-12, 02:05 PM	#2
MN Renovator Less usage=Cheaper bills Join Date: Nov 2010 Location: Minneapolis, MN Posts: 939 Thanks: 41 Thanked 116 Times in 90 Posts	My thermostat has the full F resolution, it doesn't skip any digits or do anything weird with the setpoints as you describe. I think your is doing it because it was likely not designed with us in mind, the US is a bit lonely when it comes to using Fahrenheit. One thing I did just realize though is that my -1/+2 temp range that my thermostat uses could be effectively increased in Celsius instead of Fahrenheit. It is sunny and 49 degrees F right now here so my furnace probably won't run until early morning so I'll have to play with it then. Edit: Interesting, removing the thermostat and flipping the switch to celcius has no effect. I suppose I'll have to pull the batteries to get the thermostat to recognize that I changed the setting. I'll wait until month-end so I can accurately record the energy data for the month before wiping it. Last edited by MN Renovator; 01-30-12 at 02:13 PM..

01-31-12, 10:21 AM	#6
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	Hahaha! That was a Model of the bench top! LOL!! __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

02-01-12, 03:29 PM	#8
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	Check out the Dallas DS1620.. You divide the temperature output number by two and it's C.. Getting F is somewhat more complex.. __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

01-31-12, 04:58 AM	#5
Solar Mike Helper EcoRenovator Join Date: Apr 2010 Location: Wellington, New Zealand Posts: 61 Thanks: 0 Thanked 6 Times in 5 Posts	Reminds me many years ago when NZ was in the throes of switching over from imperial to metric, a certain Govt science laboratory was getting a new lab built, the room length stainless steel bench top came back from the fabricators and didnt fit; its original spec was in feet\inches and the fabricators used metric so this tiny bench top with 10 hand sized sink units arrived much to everyone's amusement except the site manager...

02-01-12, 09:43 AM	#7
MN Renovator Less usage=Cheaper bills Join Date: Nov 2010 Location: Minneapolis, MN Posts: 939 Thanks: 41 Thanked 116 Times in 90 Posts	I pulled the battery after saving the monthly data and watched it run through a few cycles. Turns out mine runs on the F scale internally and when switched to C it will convert to C on the display but when it cycles it still shows the same temperature and shut off 1 degree above in C when in reality it is still going down 1 degree F, and running until it is 2F above and shutting off. Interesting experiment as it seems be behave opposite of yours. I actually checked the manual and it confirms that it is -1f/+2f and doesn't change when displaying C.