Question about Heating & Cooling

1 Answer

I have seen heat pumps that use a 90-340 switching relay and a ODT as a vary basic method of controling the heat pump and furnace Beside the defrost timer and heat pump t-stat what else is needed and do you have a diagram? I am installing a Trane XB heat pump to a Lennox furnace with a Fuelmaster 21 fossel fuel kit(with some signs of water damage on the board)Will the 90-340 work? Thanks Randy

Posted by on

  • airsummitcom May 17, 2009

    Sorry for the delay and thank you for the speedy reply it was vary helpful.

×

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    President:

    An expert whose answer got voted for 500 times.

  • Master
  • 2,559 Answers

Hey here is a link to the wiring diagram for a goodman,But it's the same for most all heat pumps.

If this doesn't fixya,Just let me know and I'll get more info.

Posted on May 15, 2009

  • Randy Hough
    Randy Hough May 15, 2009

    The diagram is on pages 12 & 13

×

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

When the heater is on the outside ac unit runs I've temporarily turned off 220 breaker low voltage pull in switch still energized how does the furnace control board fault occur


Are you sure this is not a heat pump. The outdide unit is supposed to run with a heat pump. If its blowing cool air its likely in defrost mode, this has to happen, though you probably have heat strips inside, possibly not wired right.

Dec 18, 2016 | Heating & Cooling

Tip

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

Why contactor on heat pump will not energize heat mode?


Heat pump and AC are basically working the same principle. When you turn on the heat pump is just like to turn on the AC. The main contactor will energize to turn on the compressor. The only difference is the 3 way valve, either switching to AC mode or heat mode. It is the most commom problem for heat pump. Check the thermostat wires for heat mode and defrost control.

Feb 05, 2015 | Heating & Cooling

1 Answer

My heat pump will not come on in HEAT or A/C. I thought I might have a simple defrost control board problem, but still no go after replacing the board and the defrost relay. I checked the pressure switch...


Hi; Need more info. How old is the equipment,look on the outside unit data plate it will give the built date usually in the top right corner. Also heat pumps can run with a faulty defrost board. I would check for control voltage at the secondary side of the transformer should be atleast 24 volts ac. Also the test post on the defrost board are for troubleshooting a defrost problem not an operational problem.When the posts are temporarely shorted the condensor will go into a defrost cycle This step will let the tech. know if defrost is operating normally. Also I have seen a reset switch manualy reset but not reinergize the control voltage. Also the outdoor unit has a delay timer that will wait for freon press. to equalize befor letting the unit operate. One more thing do You now if Your tstat is operating normally. One more idea is the defrost sensor if faulty it can leave the condensor in a defrost state of operation. This intern will sometimes go to heat strips because they are used in the defrost cycle to warm up the air conditioning going on durring a defrost cycle. One more thought is does the control contactor have 24 to 27 volts going to it if so replace the contactor. To test this using a voltage meter and touch after waiting 5 min. both sides of the coil. Remember voltage is deadly so ..When in doubt call a qualified tech.I ASSUME NO LIABILITY FOR INJURIES TO YOU OR THE EQUIPMENT BE CAREFULL!!! IF YOU GROUND YOURSELF BETWEEN 230VOLTS THIS BE VERY BAD...alpharome416

Jan 23, 2010 | Ruud UBHC Air Conditioner

2 Answers

MY HEATER BLOWS HOT AIR THEN BLOWS COLD THEN HOT THEN COLD,ICHANGED THE MOTHER BOARD, RELAY SWITCH, AND THERMOSTAT, IT IS RUN FROM A HEAT PUMP WITCH I HAD CHECKED AND IT WORKS FINE


I have a lux electric thermostat my furnace will blow out heat for about one hour to maybe three then it will start blowing cooler air,I then cut it off for thirty seconds or longer once I do that it will start blowing out heat again then it will repeat it self again what could be the problem.

Jan 07, 2010 | Heating & Cooling

2 Answers

The furnace wont turn on even though it says it is


not all digital thermostats are compatible with the manufacturers circuit control boards in the furnace. Hunter has had this problem several years ago. Other than that you may have miss wired the unit. usually the furnace is used as backup heat (during defrost) or emergency heat if your heat pump konks out. Are you switching to emergency heat for a furnace call?

Nov 24, 2009 | Hunter Fan Company 5/1/1 Programmable...

2 Answers

24v wiring for RHEEM heat pump


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

Jul 02, 2009 | Ruud UBHC Air Conditioner

1 Answer

Trying to find the fuel pump FUSE.


There is no fuse specifically dedicated to the fuel pump on this year and model of Suburban. This Suburban is equipped with dual tanks and as such has two relay switches, primary and secondary, both of which are located at the main fuse box in the engine bay, that power up the respective fuel pumps.

The closest fuse (15A) controlling either of these relays also powers up the main control module (located beside and below the main fuse box). So, if one needs to disconnect the fuel pumps from functioning, then the only effective method is to disconnect the fuel pump relays.

May 27, 2009 | 2003 Chevrolet Silverado Ss

1 Answer

3 amp fuse blows after three hours on Goodman 4 ton 16 seer pump


I would suspect you have a problem in the defrost circuit of your heat pump. there are a couple of things you can try. first just run the system on emergency heat and see what happens. you could have a defrost board that is shorting when it kicks into defrost. it sends a signal back to the furnace so it will come on during defrost. if you do not blow a fuse as long as you are running in emergency heat, i would suspect the defrost control board. also you could have a dead short in the wire that runs from the "w" terminal on furnace control board, out to the heat pump. keep in mind that any of the wires could be the cause and i am just tying to give you the most common things. your furnace will still run if you unhook all the low voltage wiring out at the heat pump. if you do this and stop blowing fuses. you know it is something on that wiring. goodl luck.

Jan 26, 2009 | Haier Energy Star ESA3183 Air Conditioner

3 Answers

3 amp fuse blows on a carrier 58mcb furnace board


Hi!!! Does your ac unit work fine?If not check your low voltage problem..You have a low voltage problem check the wire going out to your condensor make sure that they are not touching..Good luck..Check low voltage wires..short in progress..

Jan 04, 2009 | Carrier 52CQ-312-4 Comfort Series Heat...

Not finding what you are looking for?
Heating & Cooling Logo

Related Topics:

85 people viewed this question

Ask a Question

Usually answered in minutes!

Top Heating & Cooling Experts

paulcarew

Level 3 Expert

2463 Answers

Dan Webster
Dan Webster

Level 3 Expert

8220 Answers

Donni Steen

Level 3 Expert

659 Answers

Are you a Heating and Cooling Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...