New owner of a T@B 400 and unwritten instruction using Dometic Cool Cat air conditioner

riooso

Firstly the Cool Cat air conditioner is a heat pump. That means it can cool, and heat. The heating capacity is minimal but still it is capable of it. I was told by my dealer that he only way to heat the T@B was with the boiler system therefore I did not worry about the setting of the air conditioner that made it possible to heat the T@B. On my maiden voyage from Virginia to my home in California the unit kept cycling on and off  couple of times a minute after cooling for about an hour. The heating menu in the thermostat should be put down as low as it will go so that it does not get in the way of the cooling process. Now the thing works great. It may be that I speak the obvious but it was sure a pain when coming home. 

ScottG

Interesting. Do I understand correctly that the heat was coming on after the air conditioner would run? If so, I'm suprised the controls of the unit would even allow that, but I have almost no experience with heat pumps so who knows.

Perhaps this explains why some people are getting such mediocre performance from the Cool Cats in the 400's.

riooso

I do know that with a thermostat in your home, for instance, you pick either heating or cooling. I had the heating set to 75 in the T@B I noticed later, so that when the unit was trying to bring down the cab temp down and it was at 80 deg that all was well because it was not close to the 75 deg heating set point. I was in some hot climates to I ran it at night and would be awakened by a warm temp while in bed.... I would then go and lower the temp and it would work and start cooing again but really was happening was that the temp was up above 80 degrees so it would work till it cooled back down to 75 . It would then wake me up again! Going to try and find out from tech support but looking back I am pretty sure that is what was going on. 

atlasb

Our 400 has 2 thermostats.  the upper one that is hard to read is for the cool cat heat pump.  The lower one is for the Alde system.  When you use the cool cat, you will want to set the Alde (lower one )  to a low temp setting like 60 deg.  you use the Alde for the hot water and when cold out side for heat.  The Cool Cat does cycle frequently and usually only runs for a short time.  We have found for us we set the fan speed for the cool cat on the low setting (select the fan then use the up and down arrows on the cool cat thermostat for either Auto, low or high setting)  By setting the fan speed to low, it will run continually but does mask the compressor sound from cycling.  We also find that by having the fan on low all the time, it keeps the temp moderated and not up and down according to when the compressor kicks on.  Also,  watch how you angle the vents.  If you have the one by the door on the floor pointing up toward the thermostat, it may let you get a warmer temp in the cabin.  You want to circulate the air through the cabin.  We also find that when the 400 has been in the direct sun for some time and is closed up, it gets heat soaked.  If you think about how long it takes your home to cool down the first time that is what is happening.  Once we get everything cool inside we keep the blinds pretty much up in the direct sun and also look for a shady spot to camp if possible.

riooso

I understand what you are telling me about he separate systems in the T@B 400. I am not always so good at writing down what the parameters because I have questions about how the system works.  The Cool Cat is a heat pump. It can heat and cool. Originally I was told that it did not heat so I thought that function was no functional in the Dometic thermostat. I later found out that is not the case. First of all, one must turn the Alde system off. There are four parts to the Dometic menu. OFF/ON, FAN, COOLING, HEATING. I have found that if you turn the COOLING temp to 75 and the HEATING  temp to 75 using just the Dometic thermostat, when the temp in the T@B gets close to 75 then compressor with turn off and on a couple of times per minute, and I know that is not normal. Originally, I too, turned on the fan all the time but the performance of the system was not very good and the cycling of the compressor continued. 

I am probably wrong about this but I will try to set it up and find out for sure. 

NorthIsUp

This was enlightening for me. Very helpful. Thank you.

atlasb

Be aware, if you turn the Alde system off, you will not get hot water for sink, shower or heat.  Also we have found that when you are setting the trailer up.  before you plug into shore power,  make sure that you have the Alde turned off.  plug into the shore power then you can turn the Alde system on.  When you are breaking camp turn the Alde system thermostat off before you disconnect from the shore power.  There are 2 low amp fuzes in the Alde and they blow easily with a power surge.  They are the lowest amp fuzes in the entire trailer.  Seems to make a difference when you hook up and disconnect from shore power.  The Alde system is totally separate system from the cool cat.  The cool cat functions on heat to about 40 degrees outside then it becomes less efficient and could freeze the cooling coils.  The Alde takes awhile to bring the cabin temp up when cold so plan on starting it as early when needed.  You may also need to adjust the hot water/ cold water mixing valve.  Usually it is set at the min. temp from nu camp.  The Alde directions are sometimes confusing and probably the system we most have a time  understanding.  Great system though.  Enjoy the 400.  We love ours!!