Thermostat cycling too often!

[KDog]

I've been testing the furnace in the driveway for a couple of hours and have decided that the digital thermostat installed by the previous owner (Per Stan's install thread and same model) cycles the furnace off and on way too often.

It seems to be too sensitive to a drop of 1 or 2 degrees and starts up again. I tried changing the "span" but that does not help much if at all.

The furnace fan (when shutting down) continues to blow until something internal cools down. Thermocouple? Exhaust? By then the temp may drop a degree and the thermostat clicks on again.

At this rate the battery will be dead before morning! It is basically running constantly.

Any ideas?

Thanks,

Kevin

 

[Barko1]

I'm sure someone more knowledgable will comment but the burner shuts off and the fan is designed to keep running until the heat exchanger drops below a certain preset temp, I believe that is the lower limit switch. Then it would all shut down but your thermostat is calling for more heat so the cycle starts again. I noticed mine works about the same when starting to heat the camper. My solution is a good sleeping bag, a low thermostate setting, and two batteries.

 

[KDog]

Yeah Barko1 that's what I'm afraid of. If there was a way to set the span to 5 degrees or more the temps might fluctuate more but you wouldn't notice it while sleeping. I WILL notice if the furnace never shuts off.

I don't have time to install a catalytic heater before our winter trip.

0 degree down bags?


Kevin

 

[Barko1]

Right after I got my fwc I took a trip to Utah in Decemberand it was 11 degrees in the AM at Green River. I had no idea how long the battery would run the furnace so I operated it manually. Decent temp then fall asleep, wake up a few hours later and reach over and crank it up. Then let it run a bit before getting out of the bag. Mine is a 0 degree down or colder but I'm a cold sleeper. I'm used to tents and sleeping under the stars so it wasn't bad. Just keep the head in or have a warm hat. I did hook another battery in parallel but still don't know how long it would run. Last trip never got below 40 so only intermittent use.

 

[John D]

Barko1, I do the same as you with my furnace. The is a little problem with condensation inside the camper when it is really cold, but not bad. Do you think there is enough insulation in the bed (matress and shelf) for extra cold situations? (That has little to do with the condensation problem.) What do you think about laying down a Thermorest on the bed for extra insulation when it is really cold? John D

 

[Barko1]

I think the mattress provides plenty of insulation for the bottom side. I never pull my Granby bed out anyway so it is double thick. Funny you mention thermorest as I has two with me last trip. When we were in UT and it was so cold the long window seemed to be the major heat loss/cold infiltration, makes sense. Anyway I figured out that a thermorest covers the window really well and provides a good layer of insulation.

I had lots of condensation in death valley but it was 56 and raining.

 

[snow hunter]

I spent last night in the camper and it was about 15 degrees.I decided to use the furnace instead of my catalitc heater because of ease last night.
The furnace kept my place about 65 and I didnt have my insulation rolls up.I cover all the windows up and have carpet on the floor though. I had to turn the furnace off before my place turned into a sauna.After a few hours I will crank it on again when it gets cold.

 

[John D]

Barko1 is brilliant! I will never be cold again.

 

[Barko1]

I will accept the compliment but I had my thermarest over the side windows
Covering the front would certainly decrease the area needed to be heated and have less fabric exposed, but I sleep up there.

 

[Darryla]

New owner of a ATC Bobcat

Hi All: I just purchased my first pop up for my Tacoma 4X4 from All Terrain. My wife is very excited as we have been camping in our camper shell for along and I need say no more.

The folks at All Terrain are very nice folks and are extremely helpful. My Bobcat is fully loaded and they gave me a great deal. I had some bad luck in trying to buy a used one so I went with a new one.

Thank you to the folks at All Terrain

Darryl Payne

 

[ScottBailey]

Hey...

I tried changing the "span" but that does not help much if at all.

Kevin,

Which thermostat is it and which span settings did you try?

 

[KDog]

Scott ,

It's the Hunter 42995B and I have tried all 3 span settings. There doesn't seem to be much difference between them.

I am able to test it in my driveway since I'm in Utah and it's pretty cold right now.

I've added carpet with ensolite foam underneath to the floor and Reflectex over all the windows to no avail.

lqhikers,

I don't know how the original stat functioned, the previous owner put this one in. I haven't even spent the night in the Hawk yet and have had all the windows closed during the tests. Once I even had the roof down and it still couldn't deal with heating the space.

I could deal with a 5+ degree temp swing while sleeping if it meant not having the damn thing running all night!

I may switch it back to a manual which hopefully wont be so sensitive.

Kevin

 

[dsrtrat]

Heating Camper

It has been pointed out in some other threads that our campers are really three season designs. More like tents than an RV. Made light and strong at some sacrifice to utility.

I have a 16,000 btu furnace in my ATC Panther and find it is ok until around 25 degrees then struggles to keep up with heat loss. 16,000 btu,s isnt really that much when you add up all the metal you are trying to heat in one of these rigs. The metal frame and skin are great heat sinks just wanting to move the interior heat out to the enterior.

You can get 16,000 btu per hour out of a single burner on a home range so you can see the problem. One of the reasons these rigs don't use much propane is they don't really put out that much heat.

You can expect the furnace to run pretty much all of the time in really cold weather. If I am out in really cold weather I just use a winter bag and cycle the heat on and off as necessary.
I crank it up when I wake up and wait until it is warm before getting up. I like the manual thermostat and find it works fine for me.
Dsrtrat

 

[KDog]

I am finding that out!

dsrtrat,

I guess that's what I am learning here. I thought they would be more cold weather capable after reading this on the FWC site FAQ:

Does the camper work well in cold weather? Yes, a Four Wheel Camper is designed to provide maximum comfort on or off road in all climates. An available 16,000 BTU furnace and an Arctic Pack option will enable occupants to efficiently and comfortably camp at below sub zero temperatures.

I does not say however that the furnace will have to run constantly to maintain that comfortable temp. Below sub zero? Unless they are using centigrade, no way!

I guess I will have to look into adding a catalytic like the Wave 3 next spring. We plan on using our Hawk a lot in the winter as a backcountry ski base. I am already thinking about rigid foam insulation around the base and a beefier home brew Arctic Pack like some have done here.

This winter we'll have to tough it out.

Cheers,

Kevin

 

[mtn-high]

FWIW..my heater works great and will run you out of the camper of you set it above 65. (We bought the Arctic Pac but have yet to use it)

The real issue I see here isn't whether the FWC is a 4 season camper...it's whether or not people want to hear the stock heater run long enough/often enough to do it's job.

So...has anybody looked into the Wiersbo radiant floor heat option?

 

[snow hunter]

dsrtrat,

I guess that's what I am learning here. I thought they would be more cold weather capable after reading this on the FWC site FAQ:

Does the camper work well in cold weather? Yes, a Four Wheel Camper is designed to provide maximum comfort on or off road in all climates. An available 16,000 BTU furnace and an Arctic Pack option will enable occupants to efficiently and comfortably camp at below sub zero temperatures.

I does not say however that the furnace will have to run constantly to maintain that comfortable temp. Below sub zero? Unless they are using centigrade, no way!

I guess I will have to look into adding a catalytic like the Wave 3 next spring. We plan on using our Hawk a lot in the winter as a backcountry ski base. I am already thinking about rigid foam insulation around the base and a beefier home brew Arctic Pack like some have done here.

This winter we'll have to tough it out.

Cheers,

Kevin


K dog

As soon as you get the wave you will be at ease with your heating issue.It is a backcounty must and with no fan you will sleep like a baby.
The stock forced air heater will also help out alot with warming the place for short amounts of time and drying your gear.
Make the home brew curtains for the liner and you will have a much warmer mini home.

 

[ScottBailey]

Span 3

It's the Hunter 42995B and I have tried all 3 span settings. There doesn't seem to be much difference between them.


From my read of the manual, you want to set your span to 3. That will give you, as I read it, a 6 degree range (3 above, 3 below) your setting.

I have just tested my Honeywell thermostat in the mid 30s. It doesn't have span, but has a "number of cycles" setting. Anyway, it cycled a lot, but worked well enough. I have an arctic pack.

Using the analog thermostat, I found the temperature fluctuated too much (i.e. the in camper temperature range is large) for me.

 

[Stan@FourWheel]

Hey Kevin

Sorry to hear that the digital thermostat the previous owner of your camper installed is not working out for you.

I'm not having any problems with my digital at all ?

But I'm using mine in my Six-Pac, so maybe with the California winters and the hard sided cab-over camper, it is working better in our situation.

I would be glad to send you my old Suburban thermostat at no charge (I don't think I will be using it again).

Just e-mail me at ... stan@fourwh.com

Name and address is all I would need, and I will drop it in the mail.

It is an easy switch to get back to the stock thermostat.


Happy Camping !


=================================================


I've been testing the furnace in the driveway for a couple of hours and have decided that the digital thermostat installed by the previous owner (Per Stan's install thread and same model) cycles the furnace off and on way too often.

It seems to be too sensitive to a drop of 1 or 2 degrees and starts up again. I tried changing the "span" but that does not help much if at all.

The furnace fan (when shutting down) continues to blow until something internal cools down. Thermocouple? Exhaust? By then the temp may drop a degree and the thermostat clicks on again.

 

[KDog]

Thanks Everybody

I'm leaving for Canada tomorrow so the Hawk is what it is. I figure all these campers are works in progress and I could already spend months tinkering and modifying just the things I've thought of so far.

Scott,
I have tried span 3, but I will try it again in the "field" and see how it goes. Analog might be the way to go if the heater runs too much. We'll deal with the temp swings.

Snow Hunter,
The Wave 3 is on the list for next winter for sure. I like the idea of quiet heat unlike mtn-high.

mtn-high,

I had the exact same thought sitting in the camper the other night. Radiant floor heating would eliminate the cold dead air in the "well" of the camper. Warm toasty feet after skiing is a luxury I'd like to have. My wife would kill for it! I've even thought of sealing between the top of the bed rails and the camper base and blowing in cellulose insulation. I think it would work if you could keep it dry.

Cheers,

Kevin

 

[mtn-high]

From sports to guns to drugs to heaters....I'm always the odd man out in the crowd, KDog. T'ain't nothin new here. LOL.

I guess sleeping with a fan churning next to the bed every night for the last 20 years or so (since the kids came and cried/woke me up even when i wasn't my turn for the feeding) has hardened me to the brutality of the Suburban heater scenario in my FWC. (that, and a nice joint before bed. LOL)

As far as radiant...it was kinda/sorta a joke...but if you are serious I have this set up in my 2nd home/cabin/weekender (a log home). Not sure how storage would work in an FWC/etc. but this is a 24 volt system that will run on solar panels with the proper equip upfront. This stuff was originally used on oil rigs in the North Sea to keep the ice of the walkways/etc. but has migrated to home use (for odd men out, like me) in Europe/Scandaniavia and the US.

http://www.warmfloor.com/

it obviously also runs on 120V...broken down to 24V via a transformer but that would regulate a person to sucky/crowded campspots where noise would be worse than the fan on the orignal heater!

it's always somethin'... but that's what keeps life interesting!

goood luck with a solution...whatever it may be.

mtn