My heat is making a really loud griding noise and it doesn't do it when we turn it to emrgengency heat... only when the regular heat is working... what cold this be?

Why not go to see doctor?

What kind of heat? Forced hot water baseboards or radiators, air vents, or steam radiators? Old or new? Single house or apartment building? What do you mean, emergency heat?

Well I wish I had some good news for you,but it sounds like your compressor bearings are going out.When your running on emergency heat the compressor/heat pump doesn't run,only electric heat strips,essentially like a hair dryer,just a fan blowing threw electric heat strips,which uses two to three times the electricity.Now there is another possibility that it could be the outdoor fan motor,If you stand by the unit and have someone turn it on you may be able to differentiate whether it's the fan or the compressor.If it's the fan you may be able to change it out yourself.The comp.is more involved and you may need a tech. Good luck.

This sounds like your outside condenser fan motor. It is an easy and cheap fix if you do it yourself. A fan motor is about $40-50 plus the $4.00 capacitor. It will do it in AC mode as well if this is case. DrTom4444

No the air works just fine it is just the heat.. and the noise isn't coming from the ouside unit it is coming from the heat pump in the laundry room...

Do you have two different units? What kind of unit is this heater. The only kind of heater that I have ever worked on with emergency heat is a heat pump that works for the AC also. Is it water cooled? We need a better description to be able to help you. DrTom4444