Thermostat - A/C - Heat.

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carson

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How about this for a problem.
Am using Coleman A/C'? (Rooftop) and they are working well. The thermostat (Coleman) is an analog version with the usual Heat-Off-Cool and Fan Hi-LO slide switches. This is also working fine except for one thing:
? ?The settings are from 40 deg to 100 deg F. The cycling (differential) is about 6 deg.
Now, when trying to keep cool ine the hot Florida weather, I am either freezing or boiling before the contacts reverse. (I am a robust Senior citizen, please don't call me a whimp? ?:D )

There is no differential adjustment available. A 2 deg. cycling would be ideal. Seems to me that a 40 deg to 100 deg range is a bit stupid? ????? . A more human touch would be 60 deg to 90 deg range. Call me picky? ;D .

Any great ideas out there from all you fine experts for a "good" thermostat? What do the mega-buck RV's use?

Carson in Florida

 

John From Detroit

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Some electronic 'stats require 24 vac to operate, and thus won't work on an RV's system

Some non-electronic 'stats use a mercury switch (Little glass tube with some silver liquid inside) and need to be leveled to operate properly,  I'd not use in an RV where you may be a few degrees off


Some 'stats use a bi-metal strip (If you've ever taken apart a turn signal flasher, it has them too) and work just fine in most every situtation,,, If you can find one with the range you want... Go 4 it
 

carson

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This is my update on my original question, which see.

I found the ideal thermostat for RV use with better specs than I had envisioned.
There are 2 models suitable, HUNTER 42999B and 42995. I bought the 42995 as it was the only one available at Wal-Mart ($19.95). It is a digital (LCD) unit using 2 AA batteries for the electronics power. It has a 1, 2 or 3 degree (F or C) switching differential (hystereses), Auto or manual fan. Perfect!  ;D
  It is extremely easy to instal, only 4 wires. (Heat and Cool). Took me about 30 minutes.

For the best write-up and instructions, do this:  Google "hunter 42999b", look for this entry:
"The collected writings of Bob Gidding". Read the text, then click on the supplied link (klenger)for the best instructions ever. Thank you Mr. Gidding.

  Hopefully this will elate some of our RV and TT friends

carson in Florida 34461.
 

Gottasmilealot

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PA
Check and see if the thermostat has an adjustable anticipator.? If it's set incorrectly for your equipment, you'll get too much of a temperature swing before the heat or cool comes on. That seems to be what you're describing. Thermostats are made to operate different brands of equipment.? Check the manual that came with your furnace /AC and see what the setting should be, then match/set your thermostat to it. Sometime there's a little slide adjustment with numbers on it in the thermostat for that purpose. If you use a home thermostat in the RV, that adjustment could be vibrating over time while travelling and changing itself, and may need to be reset.

See "Furnace Runs Constant Short Heating Cycle" about 1/4 way down the page.? They explain the anticipator setting.? Hope it helps.
 

carson

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Keith, thank you for your information.
  I understand what you mean re anticipator. My old Coleman analog (spring type) cycled at 5-6 degrees.  The Hunter one is o total digital unit, where the cycling time is programmed with "button pushing" up to 3 degrees. I will have to make some more extensive running tests to see if there will be any hickups.
  I did get the information from RV folks, who have done this some time ago, and they just love it.  I hope I will find no surprises.
    Will keep the forum advised when I have news.
  Other comments from forum users will be appreciated.
Thanks again, Keith

carson, Florida.
 

carson

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Hello again,
FYI I have now run tests on the new digital thermostat. It is working flawlessly in both the Heat and Cooling mode. The temperature cycles within 2 degree (F), just as I desired.
I opted to connect only the LO-FAN mode (no mods required), as I never used the Hi speed  with the old analog thermostat anyway.(seemed to be excessive).
  I am now a happy puppy. :D



             
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(")__(")_/      carson, FL





                           
 

Gary RV_Wizard

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Thanks again, Carson. I've made a note of the brand and model you used in case the question arises again.

Where in FL are you? We live a short way east of Ocala/Silver Springs, out in the Ocala Nat'l Forest.
 

carson

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Florida, USA
Thanks for the note, Gary

We live in Lecanto, FL. It's about 5 miles East of Crystal River on Hwy 44.
Lecanto is in unincorporated territory, but very busy now. Lots of new building going on.
Have been here 6 years now, originally from Washington State.
Having a good time here in retirement.

carson
 

John From Detroit

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carson said:
I opted to connect only the LO-FAN mode (no mods required), as I never used the Hi speed  with the old analog thermostat anyway.(seemed to be excessive).               

Just a note: should you ever re-consider connecting only the low speed.. Pick up a single pole double throw toggle switch just about anywhere (Radio Shack comes to mind) and hook low and high speed leads to it's switched (outer) leads, hook the center terminal to the thermostat (Where you currently have low speed hooked up) and you now have a speed switch
 

carson

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Florida, USA
Thanks for the info, John.

I considered doing that. I have the instructions for the set-up, but decided against it (for now), as the lo-speed is adequate. Maybe if I hit Death Valley, I'll reconsider. ;D

Cheers, carson
 

29er

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2845 Sorrel Street, Las Vegas, NV 89146
For quite a few years Crystal River was the choice for the final test for my non-professional (recreational) scuba diving students. It was a great place but as all things happen, it got tightly regulated because of those "wintering" sea cows. Most people never realize that Florida has so many underground rivers, yet they scratch their heads about sink holes. Must be global warming?
 
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