Hiiiii..... I have samsung Thermostat AC, But i dont know how to use the warmer / heater for the same. I dont know about the model number but its one of the old AC written thermostat. Now help me out how to operate heater on the same..

number of possibilites for no heat.

1. Your engine thermostat is broken and stuck in the on possistion. In the winter months, if its stuck in the open posistion, the vehicle may never get warm enough for the heater to blow hot air (i had this problem once, 13 degrees outside and even tho we had been driving for an hour, not a single bit of warm air... fixed instantly with new thermostat) this is a cheap repair

2. you have a clogged/broken or something has happened to your heater core, it is located in the dash somewhere and hot coolant flows into it. This is not terribly expensive, but labor cost may be a bit high, sometimes there not easy to get to

3. and least likely is that your heater door wont open. Does your a/c still work fine? if yes, if you leave the ac on, and turn it from cold to hot, does it stay exactly same temp or cold? or slightly warmer? if it stays the exact same tempature of cold and you cant tell that anytinh has changed, the door that closes the ac and opens to heater could be stuck/broken, etc. or the cable or electric wire controlling it could be bad..

that concludes 3 reasons you could be without heat, as far as your electrical goes, I would make sure all your fuses are in good, otherwise, who knows, electrical in cars is a whole nother ball game

you need to change the differential pressure to 3 degrees.that means the unit will not kick on unit it is 3 degrees warmer then the setpoint

You need to know the size thermostat you put in the lower temp thermostat the warmer the engine gets sooner. You may need to replace the heater core.

Most times the heat strip is an option that can be installed but is not currently installed. If you check your owners manual, there should be a model number of you AC unit, or you may have to remove ceiling grille, and get model number off the bottom of the upper unit. There will probably be 2 sets of numbers, one for upper unit, and one for the lower unit where the controls are. Write them both down, and get back to me, and I'll see what you have, and what you'll need to get it working. You can try heat setting and see if any heat is felt, just to be sure it isn't already there. You won't get a lot, just slightly warmer air, as it's won't heat entire trailer, but will take a little bite out of the air. Also when/if you remove grille on ceiling, look for a heating coil in opening when exposed.

Your refrigerator has an Adaptive Defrost control board located inside the fresh food compartment and behind the control panel where you adjust temperature. This is the most likely reason for your troubles the part number is 12002495 The next most likely reason is the defrost heater part number 12049801 and the defrost thermostat part number is 67003377 But replacing the ADC is the main problem for your refrigerator and should be checked and replaced. Checking the defrost heater and defrost thermostat would be a good idea too, Thanks, Sea Breeze

Three possible reasons, you have a main control board inside the fresh food section that may be defective. It's hiding behind the controls, then the defrost heater and defrost thermostat inside the freezer. I think I found the board replacement. we just need to look at the board with power unplugged to fridge. We will go from there if you need my help please double check the model number. I found 2 similar numbers but not yours. I will walk you through this if you want, let me know, Thanks Sea Breeze

This link may help you identify what you need. What year is your trailer, & AC unit. Have a model # handy ?Have you checked your operators/owners manual ?
http://www.dometic.com/enus/Americas/USA/RV-Products/climate/ac-display-page/?productdataid=66938

go to this link, www.honeywell.com. In the search box, type in the model number.

Check your thermostat and mode selector setting, thermostat setting should be set at warmer and mode selector setting should be at low heat or hight this is applicable for manual unit.
If it is a remote control just set the remote to heat mode.

sample only

Go to www.honeywell.com and search their data base for your model of thermostat. You wil need all the numbers of your thermostat to be able to search. Once you find it, download the installation manual.
Good Luck.