I am installing a used heat pump into my exsisting gas furnace. All have left to do before charging is wire up the low voltage for the heat pump. I can't seem to find out where the wires go from the heat pump. It has 4 wires:
The red wire goes back to the furnace red, the blue back to the thermostat blue, the brown back to the furnace C terminal, the yellow back to thermostat Yellow (if there is a Y terminal on that furnace, land your Y's there. The purple wire outside comes back and ties to the W terminal on the furnace. Now you have a dual fuel unit so you will need a dual fuel kit or a thermostat that has dual fuel capability along with an outdoor sensor.
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
A Ruud Achiever gas furnace I believe came in a two stage model for heating. What this means is that you will have a high and a low setting. Your furnace should have two wires that control the heating cycle a W1 and W2. This should correspond with the terminals on the nest thermostat. You may run into issues if you do not have enough thermostat wires to control the furnace. If you are ever in the need for Ruud And Rheem Gas Furnaces we offer a great selection online. Shop Natural Gas Furnace. We also have a chat line which can provide technical support.
Gas valve should only have a couple of wires...24 Volt & common. the blower will use one speed on a gas furnace & a common. If you have AC or a fan switch on your thermostat, then the high speed will also be connected on the blower.
Are you talking about a pro 5000 Thermostat??? if so then NO it will not work.With this stat you do not have a temperature lock on the heat pump. Say you don't want the heat pump to run below 25 degrees. it won't shut the heat pump. And you don't want the heat pump to run at the same time as the furnace. With the Pro 8000 3 heat and 2 cool thermostat you can lock out the heat pump at 25 degrees outside an turn the furnace on. You will have to install an outdoor thermostat hooked up to the pro 8000 it usually comes with the stat. Honeywell products.
IT SOUNDS TO ME LIKE EITHER YOUR SYSTEMS LOW VOLTAGE WIRING IS INCORRECT, MOST LIKELY @ THE FURNACE. IT COULD ALSO SIMPLY BE THAT WHEN THE TECHNICIAN THAT INSTALLED THE T-STAT AT START-UP DID NOT GO THROUGH THE INSTALLER SET-UP & CHOOSE THE CORRECT SETTINGS FOR A DUEL FUEL SYSTEM. TRY THIS " SET THE THERMOSTAT TO EMERGENCY HEAT, WAIT A MINUTE OR TWO & SEE IF THAT TURNED GAS FURNACE ON. IF SO THEN IT'S A SIMPLE FIX IN THE WIRING OR PROGRAMMING & NOT SOMETHING MAJOR! GOOD LUCK!
Brown wire connect to com C on terminal block in your furnance (0VAC from 24VAC transformer)
Yellow turn on compresor (hot wire from 24VAC Transfrormer)
Blue switch Valve from AC to Heat (hot wire from 24VAC Transfrormer)
Purple prevent starting compressor in Heat pump and furnace in same time
/* Style Definitions */
mso-padding-alt:0in 5.4pt 0in 5.4pt;
font-family:"Times New Roman";}
Thermostat wire color codes
explained. Please note. Not all installers use the proper color codes when they
install or replace equipment. It may be necessary go go to the furnace or
outdoor unit to verify what wires are for what purpose. Also be sure there are
no splices in the wire that could change the wire colors between components.
or Rh (Red heat) 24 volts from equipment.
cooling) 24 volts from transformer in cooling equipment.
Note: If only furnace has a
transformer and cooling equipment does not jumper Rc and Rh.
sends 24 volts to furnace control to start the heating cycle.
W2 (no standardized wire
color, usually whatever wire color is available) controls second stage
Note: W2 is most often used
for heat pumps to control what is called emegency heat or Auxillary heat, and
most often will use the white wire.
often (blue) is used, controls cooling
unit (outdoor condensing unit) also is used for heat pump heat.
Y2 (no standardized wire
color, usually whatever wire color is available) controls second stage
controls the fan "on" operation of the furnace/air handler. Also
often is used to start the blower for many electric furnaces.
most often brown but can also be black or other color available to
Energizes heat pump reversing valve for cooling (Trane and most other
Energizes heat pump reversing valve for heating (Rheem, Ruud and
yes i can , you need to hookup the r and the o together so that the reversing vvalvce is allways energized . so with that im mind send r,y,c,o to theout side unit. at the ahu you'll hook up the 5 wires for the furnace, r g w1 w2 com and at the thermostat r,w1,w2,y,g,com,o then you will be set (the o get hooked up to o and goes straight out side.
If back-up heat comes on when a/c is turned on and then the back up heat turns off shortly after the a/c turns off, then the low voltage wiring is NOT correct. Your "R" terminal is basically your "hot" and your "C" terminal is basically your "neutral" to simplify explanation. The Furnace supplies the "R" power to the thermostat and then depending on what wire the thermostat sends the power back on determines what the system does. The thermostat terminals are as follows "G" is fan, "W" or "aux" is elect heat, "Y" tells the outdoor unit to run, "O" or "B" tells the outdoor unit whether it is heating or cooling, and "E" is emergency heat. "G" should connect from the t-stat directly to the furnace and go no further. "W" or "aux" AND "E" should both connect to your "W" or "W1" terminal in the furnace, there should also be a "W" connection to the heat pump ( this allows the H/P to turn on the elect heat when the unit defrosts) "Y" and "O" or "B" may or may not connect to a terminal in the furnace, usually they just pass through the furnace from the t-stat to the H/P and get wire nutted in the furnace. Now, here is the key. As I mentioned previously "O" or "B", a system will only use one or the other. The entire industry (except for Rheem and Ruud) uses the "O" terminial which has 24v on it when you are cooling and no power when you are heating. Rheem and Ruud use the "B" terminal which is just backwards, 24v in heating and no power in cooling. this could also be your problem if the t-stat thinks it is telling the H/P to cool but the H/P is actuall interpreting the signal to heat. Check your amp draw on the furnace, if you have anything drawing 15 amps+ then it is most likely the actual elect heat running, if not then check the "B" terminal. Most universal t-stats come set from the factory to use the "O" terminal which is more common. Usually this can be changed in the installer setup menu on the stat or sometimes the stat will have separate "O" and "B" terminals