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I have a heat pump made by ICP, it is a N4H3 and F4M4X air handler. I would like to install a digital wifi thermostat that will allow me to control the aux and heat pump lockouts. recommend?

I currently have a Honeywell Vision Pro IAQ thermostat installed.

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Posted on Jan 02, 2017

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SOURCE: I have a new York hybrid heat pump/gas furance

Did they check the sensor in the plenum. You are suppose to have bonnet sensor to switch from heat heat pump to gas whaen it is to cold for the heat pump. The bonnet sensor may be to bad. The unit is cycling ever five minutes because it may have five minute time delay.

Posted on Dec 15, 2009

  • 9 Answers

SOURCE: I am trying to wire a Honeywell Vision pro Th8000

C/U - A/H - T
R - R - R = 24V
C - C - C = COMMON
Y - - - Y = COOLING
G - G = FAN
make sure the stat is set up for heat pump
Not sure what b or d are. i would double check the schematic on the condenser for the reversing valve wire.

Posted on Dec 16, 2009

  • 43501 Answers

SOURCE: Honeywell TH8320u Vision Pro 8000 Digital keeps calling for heat

If the thermostat is not over shooting the temperature than don't worry about it.
These thermostats are very sensitive and will turn the heat back on even before the degrees drop on the display. Often they will shut down before the display changes also. You can change the sensitivity of the thermpstat if you read the directions and change the cycles per hour to a less number. There is an installers program in there that you need to push a combiunation of buttons to get too. The instructions tell you how to do that also.

Hopefully you did not throw away the instruction manual for your t-stat.. :-)


Posted on Dec 28, 2009

  • 123 Answers

SOURCE: i have a honeywell vision pro IAQ stat

That sounds like a tstat problem and that you will need to replace it.

Posted on Jan 27, 2011

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Howto hook up th8320R1003 to heat pump

Byron, unless you have thoroughly familiarized yourself with the terminal designations on all three components, t-stat, air handler and heat pump you shouldn't attempt connection of the control. There are many variations of what will work and many more variations of what will NOT work.

No mention of outdoor sensors, so fine tuning of the electric heating stages to match the heat loss of your house (for most efficient operation) doesn't sound possible.

I know, this answer didn't help but there is no simple answer without having all the components in hand.

Mar 05, 2015 | Honeywell TH8320R1003 VisionPRO 8000 w/...


Thermostat wiring terminals and colors

R - The R terminal is the power for the thermostat. This comes from the transformer usually located in the blower section for split systems but you may find the transformer in the condensing unit. For this reason, it is a good idea to kill the power at the condensing unit and the blower section before changing or working on the wiring at the thermostat. If you have a package unit then the transformer is in the package unit.
Red for the R terminal.

RC - The RC terminal is designated for the power for cooling. Some HVAC systems use two transformers. A transformer for cooling and a transformer for heating. In this case the power from the transformer in the blower section would go to the thermostat terminal. It should be noted that a jumper can be installed between RC and RH for a heating and cooling system equipped with a single transformer.
Red for RC terminal.

RH - The RH terminal is designated for the power for heating. See RC above for an explanation. It should be noted that a jumper can be installed between RC and RH for a heating and cooling system equipped with a single transformer.

Y - This is the terminal for cooling or air conditioning and goes to the compressor relay. Typically a thermostat wire pull is made to the air handler on split systems and then this wire is spliced for the separate wire pull which is made to the condenser. Some manufacturers put a terminal board strip near the control board in the air handler so a splice is not needed.
Yellow for Y Terminal.

Y2 - This is the thermostat terminal for cooling second stage if your system is so equipped. Many systems only have a single compressor but if you have two compressors which should only operate off of one thermostat then you need the Y2 thermostat terminal for second stage cooling.
*The most common color I've seen used for this terminal and wire designation is light blue but this varies and is completely up to the installer what color to use. Most installers use the color coding as noted but be aware that some do not use the thermostat color coding.

W - This is the thermostat terminal for heating. This wire should go directly to the heating source whether it be a gas or oil furnace, electric furnace, or boiler,
White for W Terminal.

W2 - This is the thermostat terminal used for second stage heat. There are gas furnaces with low fire and high fire and some depend on control from a two-stage heating thermostat with a W2 terminal. Heat Pumps use staging for auxiliary heat and need a W2 terminal.
*The most common color I've seen used for this terminal and wire designation is brown but this varies and is completely up to the installer what color to use.

G - This is the thermostat terminal used for the fan relay to energize the indoor blower fan. On a split system the blower fan is in the blower section while with a package unit the blower fan is in the outdoor package unit.

Green for G Terminal.

C - This is the thermostat terminal which originates from the transformer and is necessary to complete the 24 volts power circuit in the thermostat but only if the thermostat consumes electricity for power. Many digital thermostats require 24 volts for power so the common wire is necessary.
C stands for common and there is no universal color used for this terminal although black is the most common color I've seen.

O or B - These thermostat terminals are for heat pumps and the B thermostat terminal is used on for Rheem or Ruud and any manufacturer that energizes the reversing valve in heating mode for the heat pump. Most other manufacturers of heat pumps will utilize the reversing valve for cooling and the O thermostat terminal will be utilized for this purpose. This wire goes to outside heat pump condenser where the reversing valve is located.

Orange for O and Dark Blue for B depending on the installer of the heat pump and the manufacturer. If you have a Trane, Carrier, Goodman, Lennox, Ducane, Heil, Fedders, Amana, Janitrol, or any other manufacturer other than Rheem or Ruud you will be utilizing the orange wire for reversing valve. Rheem and Ruud will usually utilize the blue wire for reversing valve.

E - This thermostat terminal is for heat pumps and stands for Emergency Heating. If for whatever reason the heat pump condenser fails and it is necessary to run the heat there is an option on heat pump thermostats for emergency heating. Basically this simply utilizes the back-up heat source many heat pumps have to heat the home without sending a signal to the condenser to run for heat.

E - There is no universal color used for this thermostat terminal designation but this should be wired directly to the heating relay or the E terminal on a terminal strip board in the air handler or package unit if you have a heat pump package unit.

X or Aux - This thermostat terminal is for back-up on a heat pump and allows for auxiliary heating from the back-up heat source usually located in the air handler.

X or Aux - There is no universal color used for this thermostat terminal designation but this should be wired directly to the heating relay or the Aux terminal on a terminal strip board in the air handler or package unit if you have a heat pump package unit.

S1 & S2 or Outdoor 1 and Outdoor 2 - Some thermostats have this terminal and it used for an outdoor temperature sensor. The wire uses for this should be special shielded wire and completely separate form the other thermostat wires.

on Jun 06, 2011 | Heating & Cooling

1 Answer

Hey, I purchased your Honeywell RTH2510 Thermostat, but I didn't even think to label the wires when I took the old thermostat off. Upon installation of the new Thermostat (2510) the Air Conditioning...

The connections that you really need to reference would be at the air handler itself. That would tell you which wires go outside to the heat pump and which wires go to the air handler. I can however give you some basics that may help.

Heat Pump Wiring
R- Red- 24v power supply. (Usually a jumper between RC/RH)
G- Green- Fan
W- White- Heat (Sometimes W1-W2, first or second stage heat)
Y- Yellow- Cooling (Same applies as above i.e. Y1-Y2)
C- Common (Most people use blue unless it is used for B terminal and sometimes cooling on older 4 wire systems.
B/O- Reversing Valve for heat pump. Either powered heating or powered cooling, depending on system installed.
Aux- Also used for heat.

Note: Considering that the installer had their own way to run all wires, use different wires, connections, etc. This is just a reference to common wiring in the field.

How the most common system is hooked up:
Red wire goes to R terminal
Yellow wire goes to Y1 or Y2 terminal
Green wire goes to G terminal
White wire usually goes to W1 or W2 terminal
Orange or Black wire goes to B/O terminal
Brown wire usually goes to Aux terminal
Blue wire goes to C terminal, unless its being used as stated above.

This is without using a fossil fuel kit or zone control board.

Where do they go from the thermostat?
goes to the air handler transformer or board and goes outside to heat pump to power low voltage controls.
Yellow wire goes straight outside to Y terminals on heat pump unless going to a board inside first.
Green goes to the air handler fan relay.
Common goes to the air handler and outside to heat pump.
Black or Orange will go outside to heat pump terminals for reversing valve.
White usually goes outside to heat pump,and inside to air handler. Will explain reason further down.
Brown will go to the air handler to the heat relay for the emergency heat.

On a call for heat, with a powered cooling system (more common).
The R, Y, and G terminals energize, sending a signal to start the blower and pull in the contactor outside. Note that the Y terminal is usually cooling, but since this is a powered cooling system, the reversing valve is not energized, causing the system to run in heat mode. If you have powered heating, the reversing valve terminal will energize also. Depending on thermostat, if you set the temp substantially higher than room temp, it may kick on the emergency/aux heat to quickly raise the room temp. On a call for emergency/aux heat, the R, G, and E/Aux terminals are energized, turning on the electric/gas heat instead of the heat pump. This comes in handy since the heat pump can only pull so much heat from outside before its not enough to properly warm the house, usually around 30 degrees outside temp. If you are running the heat pump and the system goes into "defrost", the outside unit will send a signal back to the air handler, through the white wire I mentioned earlier, to tell the emergency/aux heat to come on while it is in defrost mode, providing heat whenever needed.

Again, this is just a reference guide to some basic wiring, but hopefully it will tell you where the problem is or at the least, give you a good start. There are variables in which things can change the wiring like a zoning system or fossil fuel kit. Even then, you should be able to get pretty close. Hope this helps and Happy Holidays!

Dec 07, 2013 | Honeywell Programmable Thermostat Heater

1 Answer

Hi I have a hb2400vd2m20 air handler and need to know what wires are needed to hook up to my thermostat its a Honeywell, as of the moment there is no heat pump it just the air handler running. I know there...

Honeywell 5000, 8000, 8000 iaq, prestige, round dial analog, digital Honeywell redlink. 1 heat 1 cool thermostat 3 heat 2 cool thermostat. does the stat u have do conventional a/c and heat pump. red wire is hot wire 24 volts not heating its your 24 volt control power. this will be r on your board and t-stat and red wire. y is for cooling mode and is yellow and will be noted y on both board and t stat. green is fan on the indoor furnace and will be g on board and t-stat and the wire is green. blue is the common side of the transformer labeled b on both board and t-stat. I did not see brown on your schematic I looked up I seen orange which is your reversing valve wire for the heat pump whether its calling for cooling or heat this is what changes the flow of Freon to make it to the indoor coil as warm Freon or cold when called for in heat or cool. the thermostat if a vision pro 8000 needs to be programmed in the installer mode which if this is the t-stat u have u need to read through the heat pump section. the green hooked to the orange doesn't look right on the print but that's the breakdown. heres your schematic

Oct 20, 2013 | Haier 2.0 Ton Multi-position Air Handler...

1 Answer

HE heat pump won't talk with old air handler?

The fact is, the air handler supplies the voltage, blower, and electric heat. In order for the heat pump to work correctly, the wiring from the thermostat and heat pump need to be hooked up right to the air handler. The thermostat is what tells which component to come on. If the fan stops, but the condenser keeps going, you either have a faulty fan relay on the air handler, faulty thermostat or wiring, faulty wiring at the heat pump, or the contacts on the new unit are sticking, which is highly doubtful considering it is working now. I hope I have helped you understand this a little more. Good luck and don't let them push you around, get someone that knows what they are looking at.

Jul 18, 2012 | Goodman Heating & Cooling

1 Answer


Generally, you would go from the thermostat to the air handler, and then, from the air handler to the outdoor unit. I don't know if you have a heat pump or not, so I will give you a simple diagram and you can contact me if you need more.

Thermostat : Y G R W and sometimes C
Air handler: Y G R W and C
Outdoor unit: two wires connecting to the contactor ( not heat pump)

Thermostat; Y--------------Y(air handler cooling)------------------one side of contactor, outdoor unit
G-------------G (air handler, fan)
R--------------R (air handler ,hot)
W-------------W (air handler, heat)
C--------------C (air handler, common)------------other side of contactor, outdoor unit

This is a typical wiring diagram. Just contact me if you have something different. Hope this helps. Stay cool. mark

Jul 10, 2011 | Heating & Cooling

1 Answer

Tempstar air handler model #nfcp2400c2 with 5kw heat strip someone has installed a contactor on inside and taken the control board out is there anyway to bypass board to use as a straight cooling only...

Yes, you need a tstat, a contactor, and a transformer.
Contactor runs the fan, transformer sends the low voltage to the tstat. Tstat turns on contactor for fan and compressor for cooling

May 17, 2011 | ICP Vortex Fan Timer Control Board For Air...

2 Answers

I just installed strip heat Rheem RXBH-1724A10J 10KW 208/240/1/60 into Rheem 14AJM36A01, RHPNHM3624JC, 3 Ton 16 SEER Air Conditioner Split System W/ GE's Variable Speed thermostat Pro 701 and it ran up...


This will help you.

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Jan 20, 2011 | Heating & Cooling

1 Answer

I have a Comfortmaker heat pump and ICP air handler-FPC3600-with 20kw back up heat. I replaced thermostat because the old one had been hit along the way and was pretty flaky. Last night the temp outside...

Did you keep notes or remember all the stat wires and terminals? 20kw should heat your home very well. Has the unit heated the house good after you changed the thermostat?

Jan 02, 2010 | Heating & Cooling

5 Answers

Wiring connection for a Ruud air handler & seeking its wiring diagram.

we are trying to install a goodman heat pump with a rheem air handler, the orange wire is hook up and the unit is still staying in the heat mood. does anyone have a wiring diagram for the air handler, their is some white wires in the air handler one with a purple strip and one with a black strip we need help

Jan 05, 2008 | Heating & Cooling

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