Digital Themostat (aftermarket install)

[Stan@FourWheel]

Deleting this thread.

I have had great luck with mine.

But if people don't like them in their FWC's, I don't want to recommend them.






.

 

[CJ8Rockcrawler]

Nice unit... I may have to go check it out.

Kyle

 

[craig333]

I like seeing what the temp is. I can't seem to keep a thermometer around for some reason. One more thing for the upgrade list.

 

[ScottBailey]

Not 12V issue

I really like this mod, except for the extra batteries... I'm certain I'll forget to keep fresh batteries in the camper and end up with a miserable cold night.

If it weren't for that, I'd install this before our next trip. (As it is, I still really like the mod, so I might try to get the info for an efficient DC-DC converter. An EEs out there?)

 

[buzzman]

Stan,

Thanks for the info. Did our discussion during my factory visit get you started on this mod? Ha, Ha! I still haven't changed mine yet, but will go look at the model you used. I think it's probably a good choice.

 

[Stan@FourWheel]

I wouldn't worry too much about the thermostat batteries going dead.

I have had the same 2 AA batteries in my digital thermostat at my house for over 3 years.

AA batteries are available at most any gas station.



.

 

[CJ8Rockcrawler]

Also in a pinch you probably have something else in the camper that runs on AA. Headlamp, small flashlight, radio, digital camera, etc.

Kyle

 

[pvstoy]

And if you dont have any batteries, jump the two wires and let the furance run for a while. When hot enough for you remove the jumper. Don't fall asleep and forget to remove the jumper....it will be VERY hot in your camper

 

[Yukon]

Thanks

Thanks Stan for taking time to post this info. I am heading out this morning on 10 day trip (Seattle to our cabin in Sierras) and will stop in route and pick up one of these..... I hope to stop by 4WC on return trip. Chris

 

[Tailfins]

I picked up one of these at Wal-Mart this afternoon. It cost $19.96 before tax. Just installed it and it seems to work fine. Some points:

1. It's a quick install, took me about ten minutes plus time fetching tools. I wanted to keep the spade thingies that are on the ends of the blue wires, so I had to chomp away at the original Suburban thermostat holes with a rail nipper in order to get them out. Did some damage to the plastic base of the Suburban, but not enough to ruin it. I also had to narrow the spades to fit the smaller screws in the new unit. Used needle nose pliers for that.

2. Mine gives a digital readout of the ambient temperature that is accurate to no more than one degree, possibly dead on. That's a nice thing to have in the camper. However, out of the box, even after I held the reset button for more than two seconds as instructed, mine showed a temperature that was four degrees too high, and it took about two hours to gradually go down to the actual temperature in the room. Once that initial adjustment was accomplished it held the correct temperature and reacted to ambient changes both up and down with reasonable speed.

3. In operation, when it turns the furnace either on or off there is a fairly loud high pitched click. I'm sure I'll get used to that and probably won't notice it after a while.

4. As for keeping extra batteries for an emergency, I think maybe an even better idea is to keep the original thermostat in a drawer in case this electronic one craps out. Then you can quickly replace it with the original and you're back in business until you can visit another Wal-Mart.

5. At any rate, it's a good idea to keep spare batteries of all sizes in the truck or the camper.

Thanks for the heads up, Stan

 

[DLN]

Help w/ Hunter Model #42995B

I've been looking for this unit on line since the closest wally is 35 miles away (which I consider a positive in most cases) but I haven't been able to locate one. Any help out there?

 

[ScottBailey]

Maybe...

I've been looking for this unit on line since the closest wally is 35 miles away (which I consider a positive in most cases) but I haven't been able to locate one. Any help out there?

Do you mean 42999B?

• Amazon
• Lowes

Or maybe the 42996? (Same as 42995 but has a remote and is slightly cheaper than the 42995 at Amazon. Why? Stock, maybe?)

Here's a Honeywell that might work: RTH111B, also instructions.

 

[DLN]

Scott,

Thanks for the reply. 42995B was the model number posted by Stan and is shown on the packaging in his post. I'm guessing it is an older item still available in wally world's inventory but has been replaced by the 42999B. I went ahead and ordered one from Amazon for about $30.00 plus shipping since we had a $50.00 credit with them so it was actually free, right? Thanks again for your help.

 

[craig333]

Ooh, I might have to get one with a remote. Perfect when you're too lazy to even roll out of bed. And not just to turn it up. Been times I wanted to turn it down too.

 

[CJ8Rockcrawler]

Ooh, I might have to get one with a remote. Perfect when you're too lazy to even roll out of bed. And not just to turn it up. Been times I wanted to turn it down too.

Glad I'm not the only one that was thinking that... I had talked myself out of it, but now... hmm...

 

[bsharp007]

Digital Thermostat

Thanks for the post Stan. This was my first mod in my Eagle FWC because the stock mechanical thermostat tends to cycle on and off too much. I just went to Home Depot and picked up one of their cheaper digital thermostats. It was easy to install and works great. I highly recommend this mod.

Will
2005 Tacoma
Eagle

 

[DLN]

Stan,

I just reviewed your post for the correct wiring layout, thanks for doing our homework for us. Also, you might want to replace those batteries in the home thermostat, they have likely served their time.

 

[Yukon]

Follow-up to Stan's Recommendation

I don't think they make the 42995B any more. I just bought the 42999B at Fred Meyer (NorthWest) store for $26.00. I have installed it and it works fine. I think Lowes also sells this brand.

The lowest temp that you can set it for is 45 degrees F. Use the hookup connections that Stan used W, and Rh. Leave the jumper in there.

Chris (aka Yukon)

 

[DLN]

I installed the Hunter 42999B last week and outside of a little adjusting in the wire location it was a piece of cake per Stan's wiring instructions. Fired right up and easy to set and use. I think the ability to set a temp and leave it is going to be the unit's best feature as opposed to the guessing you had to do with the stock unit. Now we just need to try it out properly on an over nighter, unfortunately that will not be until spring, seems like a long way off.

 

[ScottBailey]

Sadly, I did install the digital thermostat and step down converter BEFORE the next trip. Should have been camping!

I selected a Honeywell thermostat because it was not significantly larger than the OEM, it was cheap, and available on Amazon.

The terminals to attach your thermostat wiring to are Rh and W. It is my understanding either wire can go to either terminal, it's just a close of the loop. The Rh to Rc loop (Hot-hot Hot-cold) is irrelevant for us and counter productive if you accidentally push over to cool. I suppose you could wire a swampy, etc, up to it though... Then you'd need to know more about your wiring...

I used some of the parts from this step down kit with this chip to build a 12v to 3.3v step down circuit to power the thermostat from the camper battery. Basically, I installed the jumper, ignored the resistors, and replaced the included 7806 6v output chip with the new 3.3v output chip.

The circuit board is wired into the fuse block and clipped to the battery terminals.

In hindsight, I really should take the thermostat apart to see if it has an internal voltage regulator that can take a 12v input... Damn, I'm almost certain I know what I'm doing when Jake takes his nap today.

Enough speculation, on to the pictures!

Before:
Just a quick referance snap before the mod.

Wires for 3.3v:
Showing the 3.3v wires fished from thermostat location down to the fuse block.

'W' and 'Rh' attached:
Thermostat is wired.

Testing the step down converter:
Yep, the sun heats the back of the house to 80 degrees in January.

Installed:
I show the old thermostat for size reference.