Being new to rving i'm On a steep learning curve as I have said before. Last nite the rear roof air would not get hot, only blows cool air, not cold like the ac was on.. I am somewhat mechanical is this something I could do myself or should I leave it to the professionals? I know nothing about the unit other than it is a heat pump... any info is greatly appreciated...
I would look into the thermostat to see if it is talking to the rear unit or dead, before taking it to someone that most likely knows less than you do in how the HVAC system works in these coaches.
Mike
If it was below 45 degrees you will not get much heat from the roof mounted heat pump
If you have a 4 button:
Comfort Control Thermostat Question/Posting New Topic (http://www.foreforums.com/index.php?topic=27355.msg223748#msg223748)
As a previous answer stated if below 45 degrees not much good. I don't like using them, like the ac they are noisy.
Here it texas it very rarely gets below 40* especially in April. It was in the mid 50' at nite
Interesting fact, especially if you pay for the electricity you use. A heat pump can supply over 12000 btu's of heat and use 13 amps at 120 volts. Best a electric resistance heater [which is basically all portable electric heaters] can do, is 5100 btu's using 13 amps at 120 volts
."Electric resistance heating is 100% energy efficient in the sense that all the incoming electric energy is converted to heat. ... If electricity is the only choice, heat pumps are preferable in most climates, as they easily cut electricity use by 50% when compared with electric resistance heating."
At 50 heat pumps are very efficient at that temp, most output 3x or more than the amount of energy that they consume. Unless they have to defrost, which I don't think the RV units are even capable of doing. Average winter temperature in KS where I live is about 47 IRC. Granted they make noise, and many people feel that they are drafty due to the discharge air temperature being lower than the body temperature. But efficient.
Newer models claim a low of 32 f. I imagine not a lot of heat at that temp.
https://comnet2.newmarcorp.com/instance1env99newmar/html/images/SS2011DometicAC.pdf
Jim - you can get modern inverter heat pumps that even go down to -14 they just burn more and more energy to go thru the defrost cycle which they can now sometimes detect when the outside coil is frosted. At temps less than about 37 ambient humidity starts freezing on the outside coil depending on your location and load on the coil. Can't fool mother nature and the COP drops below 1.0. past that point it's a game of liars poker with the deep pocketed Asians able to win every hand. Lots of politics, slick marketing and graft. JMO.