Heat Pumps and Electric Heating - blowing cold air

I have a 3 year old Armstrong Air Heat Pump and Air Handler in the basement, the T-Stat is a White-Rogers....it is approx. 0F today....Is it normal for 50 degree air to come out of the registers when the Pump is in defrost mode, are my electric strips pooched? I placed one of those Thermometer/Humidity gizmos on my floor register and the Temp dropped to about 50, the defrost finished pumped kicked in and the Thermometer went up 80.....what should happen if I throw the switch over to emerg.???

ok I threw it onto emerg.heat and the strips came on.....the temp gauge went up, I also forgot to mention I have an air exchanger on the system as well, it is controled by a humidistat on the wall next to the T-Stat. Just before I tried the emerg. heat the pump went into defrost cycle again..felt like the a/c was on register temps drop again...felt the pipes from the comp. the biggin was cold the wee one was warm.

When the heatpump goes into defrost it is the same as when the AC is running . BUT the electric elements should come one at this time also .So the unit dont blow cold air. Ihave found that when its 20o or below outside I go over the EME heat . Till its back up over 20o.

Well the service tech came out..........turns out my "Reversing Valve" is faulty, they also said they where going to install an Outside Thermostat that will shut the pump off at a set temp. They have to drain "freon" and install new valve. Sound right? Running on Emerg. heat right now.....a couple of times last year and this year heard a cluking/clicking noise coming from pump.....will keep all posted.

Not there so out of the box here. But you said it went into defrost and blowed cold air.
on my floor register and the Temp dropped to about 50, the defrost finished pumped kicked in and the Thermometer went up 80....
You said the elements didnt come on when in defrost. But when you went to EME you had heat. I sure dont see what is wrong with the 4 way valve sounds more like in the tstat are its not wired right
You said
Just before I tried the emerg. heat the pump went into defrost cycle again..felt like the a/c was on register temps drop again...felt the pipes from the comp. the biggin was cold the wee one was warm
I sure dont see a bad 4 way valve Or why you need a OT cut off tstat with electric back up heat

Ok been almost 10 months and they came back to fix my Heat Pump...the guy said your reversing valve is fine...but we will install an Outside tstat.....I don`t need an outside tstat, I know when its cold outside....I should have him check the indoor tstat when he comes back..or just replace it all together....its a White -Rogers...wired as follows:
Grey Wire jumped between w2 & E
White Wire to w2
Orange wire to 0/B
Green to G
Black to C
Yellow to Y
:coffee: