Alarm light keeps coming on and stops blowing cold air out front and blows cold air out the exhaust hose instead?

sounds like the compressor has died and is tripping its overload protection. Give it a good funeral, and next time, buy a brand name model.

this style unit needs an exhaust hose attached to the rearand be placed out the window to exhaust the heat that is removed from the air in the room, you will also have to empty the condensate drain bucket when it gets full.

Since the unit is new and under warranty and hopefully you have registered it with Delonghi. Your best bet, is to contact their Customer Support Rep 800-322-3848. Doing it this way has you totally covered.

Yes, hose needs to connect to outdoors, since it operates as a heat pump. You'll notice cold air blowing out the exhaust when in heating mode, and hot air blowing out the exhaust in cooling mode - unit exhausts opposite of temperature you want.

sometimes the snow falls down in june, sometimes the sun goes round the moon

take a garden hose or somthing with high water pressure and spray out all of radiators in the front of machine. This will clean out all the dust build up between all the rads and will cause your fan to cool the ac fluid as well as the others

always check the coolant first, then feel both heater hoses to see if they are equally hot.
if one hot and one cold, then the heater core is clogged
if both hot then you have a blend door problem.
on the a/c there's some time a rear unit that blow cool air even the front does not

Have you checked the coolant level? What you describe is exactly what happens if the coolant level is low. When stopped at idle, hot coolant is not circulating through the heater core, so no heat. As the engine increases in rpm's when you pull away from the light, the water pump is spinning quicker, and some coolant is making it to the heater core. So check the level, and if it is low, keep an eye on it to see if it drops again. That of course indicates a leak somewhere. Get it fixed, as overheating the engine leads to costly repairs and worse case a new engine. Let me know how you make out with this.

I recenly had the same problem on my 1999 suburban, even after I replaced the whole ac system.
The heater valve, which is under the air filter area was not closing, causing heat to be blowing over the evaporator core. I used a zip tie to keep it in the closed position, and ac went from 70 degrees to 40. I think the vacuum switch is bad, 40 dollars (dealer part). You can also pull the vacuum hose off the switch, which is on the firewall and connect it dirctly to valve and it closes the valve, but fits loosley. Use silicone around vac hose if you go this route.

Hello , I can try to help you out on this one , It sounds like what is happening is that your exhaust vented up is condensating from the heat in the pipe and the cool in the attic or wherever the exterior of the exhaust pipe travels. It is very common because your exhaust/flu pipe is not insulated.
To fix this issue you must drain the water/condensation from the small 5/16th hoses in front of the blower assembly , just pull them loose and angle them downward to drain. This should fix the problem if this is the problem.
Let me know how it turns out or if you have anymore questions. Phil