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Douglas, HVAC Technician
Category: HVAC
Satisfied Customers: 3089
Experience:  Manufacture Rep for Major Brand, Technical Trainer, NATE
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What does auxillary heat mean?

This answer was rated:

What does auxillary heat mean?

Optional Information:
Make : LuxPro
Model : PSDH121

Already Tried:
I tried pushing up and down arrows to reset. I didn't get a manual with this and the online manual doesn't speak about auxillary heat . It seems to lose heat when this appears in the display window

Auxiliary heat is referring to a back up heat source.

As an example.

You can purchase a heat pump with a natural gas furnace. The heat pump would be your first stage (primary), and your gas would be the second stage (auxiliary).

Another way to set this up would be a heat pump with electric heat strips as an aux heat source.
Customer: replied 7 years ago.

I don"t believe I have another heat source. We live in Texas and have had extremely cold weather. Would this go into this mode to protect the unit? If not, how do I reset that thermostat to come out of auxillary mode? My thermostat is dropping in temperature and it is getting colder in my home.

What kind of heating do you have?
Customer: replied 7 years ago.
Electric strips, or electric as in a heat pump?
Customer: replied 7 years ago.
its an electric central air unit outside in the backyard and there is a hot water heater in the garage.. thats all i know.. im a woman living here by myself
What kind of thermostat do you have?
Customer: replied 7 years ago.
What is the model number?
Customer: replied 7 years ago.
ok i just found it inside the face plate PSDH121A
can you take the thermostat off the subbase (back plate) and tell me what wires are connected to what terminal?
Customer: replied 7 years ago.

ok Black-E

Yellow - Y

Orange- o

White W2

Red R

Green G

Blue C

ok this suggests you have auxiliary heat.

Let me look up your thermostat... bear with me.

While I do that, does your thermostat have an emergency heat switch or is it just

Customer: replied 7 years ago.
yes i have an emergency heat switch on this thermostat. Should i switch it to that?
well maybe, but not yet.

The wiring also suggests you have a heat pump so the outdoor unit should run when you are in the heat mode. That's not to say the system has not been replaced at some time so we cant be sure without a little digging.

OK,lets go ahead and switch the thermostat to Emergency heat and turn it up a few degrees and see if you get any heat.
Customer: replied 7 years ago.
NOPE it didnt come on .

ok... interesting..

OK, do you have a paper clip handy? I want you to fashion a little jumper and pop the thermostat back off so you can see the wires.

I want you to touch one end to the R terminal and the other to the W2 terminal and hold it for about 2 minutes and see if the heat comes on. (no you will not get shocked)

Customer: replied 7 years ago.
WOOOOHOOOO! YES IT IS ON ! wait it just turned off becuase i just came back to my laptop to respond to you
thats ok...

lets do that again from R to E....
Customer: replied 7 years ago.
Yes it came on-as long as I hold it it stays on-
well... it should have come on with the thermostat in emergency heat mode at the very least... I am sort of concerned the thermostat is poo poo.

I'm not a big fan of Lux... let me think up a solution to get you through the night.
Customer: replied 7 years ago.
this thermostat is only 5 months old!~ CRAP! should I have kept it in emergency mode after i did the jumper stuff? i put it back to regular! will that make a difference .. thanks for taking the time douglas.. i appreciate it very much..kathy ill keep on with you until you feel you have become exhausted.. with it!
By the way, here is the manual for your thermostat.... Click Here
Customer: replied 7 years ago.
I'm here.... trying to come up with a McGyver solution till you can get a thermostat tomorrow.
Customer: replied 7 years ago.
i missed the manual you sent to me.. i thought we were disconnected. is there a way for me to make the paperclip stick on to the two screws.. will that work.. or will it burn out the unit!
no it will over heat the house. not a good idea

Ok lets try this.... Just for tonight.

Make a note to yourself where all the thermostat wires are connected.

Remove the Yellow wire from the Y terminal and put some tape over the end of the wire. and tuck it away. You'll need this wire tomorrow so don't tuck too far.

Then I want you to take the black wire from the E terminal and move it to the Y terminal. Then put the thermostat back on the wall. Set it to heat (not emergency heat) and set it up 2 degrees above the room temp and let me know if the heat kicks on in a minute or two.
Customer: replied 7 years ago.
ok so far it is on.. how long can i sit up watching it to make sure it will stay on> or will it just stay on becuase you are McGIver's cousin..? ha haha
well... its on... ok turn the thermostat down below the room temp. It should shut off in a few minutes or less
Customer: replied 7 years ago.
ok it was 73 now its 71 and the unit shut off now! now what?

ok... this will work for the night..... Set it where you want it to be comfortable... no not 80 if that's what you were thinking...

Now a little bubble gum and a shoe lace may keep a helicopter from crashing until it can land but it's not a permanent fix.... You need to go to Home Depot or Lowes or something and get a new thermostat tomorrow.

Get one suitable for a heat pump with aux heat. (2stage heat/1 stage cool). I recommend a Honeywell. (this is where you nod your head in agreement and say "I Promise")

Customer: replied 7 years ago.

we are going to tell everyone to come on and ask just for DOUGLAS>. YOU ROCK>> im a nj woman living in Texas and I dont know anyone who repairs and i dont trust these huge commercial guys down here.. they seem to sabotage things..

thanks douglas.. i appreciate the time you took and the MCGIVER ways... rigging is my thing... ha ha ha now go to [email protected]


where in TX?
Customer: replied 7 years ago.
fort worth... and I am putting in $50 bucks for you .. you have saved me from freezing.. thats why i came to Texas .. hated the cold weather.. ah haha ha.. its been in the teens... here.. oh well thanks again.. you ROCK!
I hate it too... I may have to come to Fort worth but as cold as the whole country is, I may just go to Cancun or Aruba and disappear into the woodwork... Thanks, ***** ***** of you.

give me your zip code, I'll tell you who you can trust in the area...
Customer: replied 7 years ago.
76137 i appreciate it very much!
ok.... Terry Tekell owns BCI mechanical.... These are good folks...

They are over in Denton but they service all around.

If you ever need service and I cant help, they will be the guys to call.

BCI Mechanical.
400 East Oak
Denton, TX 76201
Phone:(###) ###-####/span>

I'm going to bed.... You take Care...
Douglas, HVAC Technician
Category: HVAC
Satisfied Customers: 3089
Experience: Manufacture Rep for Major Brand, Technical Trainer, NATE
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