Getting around the 40 degrees or warmer heater limitation

MandMStevens

We recently purchased a T@B and love it... however we live in a Northern Western state and we camp a LOT in colder temps... we are completely disappointed to ready that the heater installed from the factory will only run if the temperature is ABOVE 40 degrees... what a joke.  If it's that warm, we obviously don't even need a heater.  Any suggestions here on how to bi-pass the 40 degree sensor that's preventing us from running the heater when it's actually needed?

Thanks in advance for any assistance on this matter!

Denny16

You seem to have the wrong end of the stick MandMStevens.  The 40-degree limit for effective heating only is for the CoolCat AC which is a heat pump, and can add some heat into the cabin.  At temps lower than 40F, it will still work, but not very well.  The CoolCat is more of an Air Conditioner than it is a heater.

The primary heater in the TaB is the Alde unit, which works at any temperature.  In colder weather it takes longer to get the heat up, but it still works.  The Alde is a convection heated glycol circulating heat exchanger, like old fashioned radiators, but smaller a d more efficient.  It works on convection circulation, warm air rising from the heater cores (radiators), and cooler air being pulled in from along the floor vent openings.  Much like radiant floor heating.

If you have 120VAC hookup available, you can set the Alde to heat with both electrical heater and gas (LPG) heating, to get faster heating up, and run the CoolCat (30-amp connection required to run both on shore power)  in heat mode, to warm up the TaB cabin a little faster.

That said, the TaB was not designed as a four season, winter weather (below freezing) camper.  But many owners have dry camped (no running water systems) in their TaBs during winter months.  The TaB does require its water plumbing to be Winterized in temps below freezing.
cheers

MandMStevens

Thanks for the quick response.  When plugged in, and the thermostat on "furnace" it will sort of kick on and run the blower for about 20 seconds, then shuts off... so if I understand from what you've posted, this is 'normal' operation for the heating unit?

DanManz

As @Denny16 said, you want to get familiar with the operation of your Alde heating system.  That little baby is a very sophisticated RV system that heats your hot water and circulates glycol through a series of registers to heat the cabin.  It's amazingly quiet and keeps the interior temperature of our 400 very consistent in all areas.  Ours just went into winter storage last week but my wife and I did one more night of driveway camping before it went in.  I had the camper plugged into a 15 amp circuit from the house and put the Alde on 1KW.  Temps were predicted to go down to around 20 degrees overnight so I also turned on the propane.  I set the Alde thermostat at 67 degrees and had to get up in the middle of the night to turn it down to 63 as it was too warm!  Outside temp went down to 18 by morning.  If you winterize your plumbing system and can work around that, your T@b will keep you pretty warm even when camping on pretty cool evenings.

Verna

@MandMStevens, what is the year of your T@B?  

NüCamp started using the Alde for heat and hot water since the late 2014 models. 

Dutchman and Thor T@B’s do not have an Alde for heat and hot water. They have the Dometic Cool Cat for air conditioning and heating down to about 40*,m my.  Some Dutchman T@B’s also have a propane heater, but not all of them. 

falcon1970

A heat pump, any heat pump, can only raise the ambient temp about 40 degrees F.  It will work at any temp but if the OAT is 10 degrees F the indoor temp will never get above 50 degrees F.  A heat pump is useful in areas (primarily southern states) where the OAT never really gets cold but is cooler than might be comfortable.  It will take the chill out of the air but loses effectiveness as the OAT decreases

Mouseketab

Correct, most home heat pumps also have heat strips when the temps drop below 40, the CoolCat does not. I have a CoolCat in my 2007, but no gas furnace. I use a small ceramic heater in the winter, and keeps the T@B toasty.

If you have a gas furnace, you can most definitely use it below 40.

MandMStevens

Thank you all for the comments and input.  Our T@B is from 2008.  

The Alde system sounds nice certainly.  This unit however has the cool-cat.  There is no option to activate "LP".  Only a thermostat with 4 settings and a temp gauge.

In the manufacturing docs it specifically says: "Note: The outside thermostat will not allow the heat pump to operate when temperatures are below 40 degrees fahrenheit"

When plugged into our generator, or to a 110 V house outlet, the furnace setting will turn on the unit under the seat/bed once the thermometer is moved up to a temp to activate the heating system.  For 20 seconds or so, there is "blowing" that can be heard from the unit, then it shuts off and that's that. No more heat or even hot air coming out. In order to get the system to 'reset', we have to shut off the thermostat and can then repeat the same 20 seconds of blowing but nothing more.  But again, no heat is produced that can be felt when this happens.

It's 32 degrees exactly outside right now and if we were camping, I'd like the unit to actually run the heater.  If this unit isn't capable of heating when it's actually cold, we're getting rid of it as it's really no better than a tent at that point.

Thanks for any suggestions or help....
Sincerely Frustrated and Cold

Verna

@MandMStevens, sorry, but you have a Dutchman T@B, manufactured by Dutchman. They do not have the Alde heat. 

Only the nüCamp/Pleasant Valley T@B’s have the Alde radiant heat since the mid-2014 models. 

Denny16

You can look at having a Truma heating system installed.  The CoolCat from that era is not going to work at temperatures below 40F, as you gave stated.  Dutchman is part of Thor Corporation, you might try contacting them.
cheers

VictoriaP

@MandMStevens If you intend to regularly camp in freezing conditions, I strongly suggest you look for a trailer marketed as a 4 season trailer. Most RVs are not designed to be used in cold winter weather. Unfortunately, if your only heat source is the Cool Cat, you’re correct that this trailer will not work for your purposes. A heat pump cannot physically do what you require. 

That said, for boondocking, you might look into getting a Mr. Heater propane heater such as this one: https://www.amazon.com/Mr-Heater-F232000-Indoor-Safe-Portable/dp/B002G51BZU They’re often used for camping, ice fishing shacks, and power outages. It’s cheaper than a new trailer, and will definitely heat a Tab. The linked model runs off 1 pound camping propane containers. Some models will work with a hose adapter that can run off a larger propane bottle.

It’s not a perfect solution, but it is one option, as is a portable electric heater if you’re camping with power.

MandMStevens

Thanks for the input and feedback, as unfortunate as it may be, we appreciate your time and suggestions.

Sharon_is_SAM

@MandMStevens - since it sounds like you plan to use shorepower, Carol’s suggestion of a ceramic heater is a good one.  I believe a propane heater has been implicated in too much moisture in a small trailer.  You are lucky to have a functioning Cool Cat in your TaB.  

Mouseketab

Check under your driver bench toward the back and see if you have a furnace. If it only blows for a bit, then there may just be an issue with it. Is your gas bottle on the front turned on?

rfuss928

The furnace position on the thermostat activates the Atwood furnace (as you said, "under the bed/bench").  If it runs for 20 seconds and quits there is a "fault" shutting the furnace off.  Make sure the gas is on and the furnace grill and outlets are unobstructed.  There is a fault indicator light behind the front grill.  The Atwood manual is in the Manuals and Files category.
Is this your thermostat?

MandMStevens

@rfuss928, yes, that is our thermostat exactly.

MandMStevens

To answer a previous question, I removed all the cushions and removed the "do not remove" board to get full and unobstructed access to the heater.  I pulled the two screws on the control panel so I could see the lights on the control board to see if, or what, the fault was... there is no blinking light showing.

MandMStevens

@Mouseketab Not sure if there is propane getting to the furnace or not, the fridge and stove both work on LP and run as expected.

Sharon_is_SAM

Here is the Atwood Heatef info

https://tab-rv.vanillacommunity.com/discussion/4393/atwood-heater-service-manual#latest

rfuss928

MandMStevens
The system resets after a power off cycle or enough time passing.  Now that you can see the board, try again.  There should be a red LED and a nearby reset switch on the control circuit board.  There is a fault code chart in the service manual linked above.
BTW  The bottom position on the SYSTEM switch should make the CoolCat heatpump function run.

MandMStevens

@rfuss928  Thanks for the update. That makes sense.  Will try that with the board open.

Question, is the heatpump needed to make the furnace run?  We've been trying to get it to work using the 'furnace' setting on the thermostat.  

Secondly, and this is an apparently stupid question, but how do we tell if propane is getting to the furnace?  I don't see any LP related switch box in the heater.

Denny16

The CoolCat and Atwood heater are independent units, the heater should work on its own.  To get the CoolCat in heat mode, try setting the thermostat to a high temp above the current cabin temp, with the selector switch in heat pump mode.
Does this control click up  one notch to heat position or are heat pump a d heat the same setting?
cheers

rfuss928

MandMStevens
The furnace and heatpump are separate and will not run together.  

When you try to start the furnace, you will hear the blower start up and after the sail switch verifies airflow, a solenoid will click starting the gas flow.  An igniter will start sparking with the gas flow and if it doesn't light after ~15 seconds, it shuts down.  You will hear a poof if it lights.  I think there is a timer that will retry after ~5 min.  It may take several tries if air has gotten into the line.  

IMO the hp function of the CC is inefficient and noisy - basically useless, .  A small electric heater or the LP furnace work much better.  OTOH it is a very capable AC.
Good luck & have fun!
Bob