It blows cold air while in heat mode - Danby DDR586R Dehumidifier

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

A dehumidifier is the same thing as a window unit air conditioner that you sit on your kitchen floor instead of installing it into a window. It will blow cold air out one side (evaporator side) and hot air out the other. (condenser side) Hot/Cold cancelling each other out, (plus a little bit of "extra" heat from running the thing) yet the evaporator STILL removes humidity from the air in the form of a puddle of water on your kitchen floor. They (air conditioners & dehumidifiers) are both essentially air conditioners only difference being is that in order to "cool" an area, the "condenser," or "hot" air would have to be moved outside somehow. Air conditioners do not "cool" air, per se. Instead, they ABSORB & MOVE HEAT from one place to another via some type of gas (freon) and a compressor pump inside of a closed tubular system. (copper,brass,aluminum, etc)

A heat pump is an air conditioner that reverses its refrigerant flow. In the cooling mode, the evaporator is cold to the room and its condenser is hot. In the heating mode, a valve reverses the refrigerant flow and makes the evaporator warm and the condenser cold.

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.

This may be caused by running the unit in continuous mode, rather than timed mode. The heat is generally is generated when the defrost mode cycles on, to defrost the cooling coils. This happens more frequently, if the air space around the unit is obstructed or it's operating in a temperature range of 40 to 60 F. Cleaning the air intake filter at least once a week, can help solve this problem, too.

Maintain a minimum of 12" free air space around all sides of the dehumidifier. Use a timed mode rather than a continuous mode. Make sure the room is within the proper operating temperature range and clean the air intake filter weekly.

Hope this helped you troubleshoot and solve the problem.

I'm not sure exactly what you have. As you listed the problem under Problem with the Danby DDR557 Dehumidifier and then said, "no heat coming just cold air". Dehumidifiers are not designed to generate heat. Is it some other type of appliance that you have?

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

Is it collecting water? The air coming out the back top half should be cool/warm. It will be a little warmer at the bottom near the compressor.