We have a Ruud heat pump that is 12-13years old & as of the last few days, it does not seem to be heating the house very well but it has been very cold for this part of the country. It works well when the outside temp is above 50 degrees. It has been in the upper 30's and low 40's. We put on the emergency heat for awhile but when we did the fan stops.

Thank you.

We have a Ruud heat pump that is 12-13years old & as of the last few days, it does not seem to be heating the house very well but it has been very cold for this part of the country. It works well when the outside temp is above 50 degrees. It has been in the upper 30's and low 40's. We put on the emergency heat for awhile but when we did the fan stops.

Thank you.
Have the freon charge checked. It may be low. The outside fan will stop when the emergency heat is on. That's normal when the electric heat strips come on and you are no longer using the heat pump operation... Upper 30's to 40 degress should be no problem for the heat pump...

Your symptoms are leaning to sounding like a Emergency Heat relay or Sequencer. Depending on your system, some companies have a control board that tells the fan to come one and if it doesn't tell your fan to come on then your emergency heat won't run. Kind of a safety feature. By saying it is heating fine until gets really cold sounds like your emergency heat not working properly... I would call tech out to check! Brian