THE MACHINE BLOWS BUT DOES NOT TAKE THE WATEWR OUT OF THE AIR

Is the condenser fan working?

dry air feels cool on the skin

moist air feels warm on the skin

this is why the perceived temperature of air from unit changes

In order to look up the filter change procedure I would need the specific model number. However, filter changes or washing should be done regularly. Look for a very simple lift-out design that is washable in the kitchen or laundry sink. Soak in soapy water and rinse with spray nozzle.

As for the symptom "Blows out warm air" this is expected. The dehumidifier is less than 100% efficient, meaning that the energy that is used produces heat in the exhaust air. A 100% efficient design would still send all the heat energy of condensation (endothermic phase change) into the exhaust air. You should expect 1072 BTU per pint (1 pound of water). This is far more than the heat of crystallization (144 BTU per pound of ice) and therefore much more sensible when you feel the discharge air from the dehumidifier. Dehumidifiers typically operate in basements to both warm and dry the area where a sump pump may be operating to remove the water that seeps through the foundation. A dehumidifier is not a good idea for warm areas of the house. This will decrease the efficiency by increasing the temperature differential needed to get the evaporator coil below the dew point to cause condensation. The condenser coil will be much hotter than expected if the unit is operated in a warm humid room. Only air conditioners which discharge condensate and exhaust air to the outside of the structure should be used to cool a room.

With heat pumps that's the way they work. In heat mode they are using the evaporator as the condenser and it blows heat out the front and cold out the back. In cooling mode, a reversing valve switches the gas flow reversing the operation of the coils and it blows cold out the front and heat out the back.

It is normal for a dehumidifier to discharge warm air. A dehumidifier is really an air conditioner - a fan blows humid room air across a cold fin coil that causes the moisture to condense on it and drip into a container - thus cooling AND dehumidifying the air. The cool air is blown over the warm coil and discharged out the back. A dehumidifier WILL normally increase the temperature of the room it is in.
You can do the same thing with sitting an A/C unit on a stool in a room. Room air will be drawn in, cold air will come out the front, hot air out the back and water will drip on the floor. And, the room will get hotter, due to what is called "heat of compression" even though you're running an A/C unit.

Dehumidifiers aren't supposed to cool your house. If anything they generate heat. How it works is, it has cooling coils that it draws air across, which causes the moisture to condense, and be captured. However the heat extracted from the air has to go somewhere, so it just blows out the other side. If you want cool, buy an air conditioner.

To condense the water (cold side) the air should be warm.

Sounds like coolant leak or compressor problem; if so, time for new unit.

Liz; Check for a fuse somewhere in the heat circuit. The master breaker in the house panel also

If it vents or blows air out the top you can put it against a wall. If it blows air out the back it will heat the wall and also impede the airflow through it and make it work less efficient. I would check with the manufacturers owners manual or their website.

Possible cause it's out of gas.

you might have to get a refridgeration mechanic to regas it, or/and fix any gas leaks