Question about Air Conditioners

1 Answer

Heat mode on trouble

A.c works good in cool mode.when change to heat mode system geting off. compressor over heating.solinoid why  valve makes trouble in some units. can you expline its works in details.

Posted by on

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 10 achievements.


    An expert that got 5 achievements.

    Vice President:

    An expert whose answer got voted for 100 times.

  • Master
  • 909 Answers
Re: Heat mode on trouble

Possibly changeover valve not functioning correctly causing high head pressure and  safety to switch off in protection mode.not the ideal DIY repair.

Posted on Oct 23, 2007

Add Your Answer

0 characters

Uploading: 0%


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


3 Points

Related Questions:

1 Answer

Why does my sanyo model KHS2472 has a red light blinking in heat mode and a green in cooling mode, does not work in either mode makes a gurgling sound when it tries to run?

The red light indicates it's either heating or in defrost mode
Check the outdoor unit if the compressor is running - the large pipe on the outdoor unit should be hot on heating or cool to touch on cooling
When in heating mode - the indoor fan will not start until the indoor coil is warm enough
If the reversing valve that changes from heating to cooling is faulty then you may encounter the same symptoms too
Probably need a Refrig Tech to have a look at it?
Good luck

Jan 07, 2016 | Sanyo 24KS72 Split System Air Conditioner

1 Answer

Why doesn't the compressor start in the heat mode

If the compressor is off and the heat coil is on - this is normal for the "E" or emergency heat setting. Check for proper connections between the Heat-pump, furnace(heat source) and the thermostat and that the thermostat is capable of controlling a heat-pump with secondary/emergency heat units. Thermostats designed for this have 4 settings: Cool / off / heat / E(emergency heat). in the "heat" setting, both the Heat-pump and Aux heat work together to maintain temperature. In the "E" setting, only the Aux heat source is used. The "E" setting should only be used in extreme cold - when the Heat-pump can no longer produce heat.

Sep 10, 2014 | LG LP153HD3A - 14,300 BTU, R410A, 9.4 EER,...

2 Answers

I have a Rheem heat pump/air handler; it draws 2.9amps with only the fan running, 13amps when the heat pump is running and 38amps with the heat strips on. My question is why the unit draws that many amps...

Sounds like it must be about a 2.5- 3 ton system. The 13amps has to be the compressor draw -normal. and 38 on the strips- normal. 2.9 fan -normal.

You may want to check your wiring to see where the outside unit gets its power. Theres nothing inside that can draw 13 amps. That almost has to be the compressor power wire.

Jan 27, 2011 | Air Conditioners

1 Answer

Heat pump heats with ac cool mode on dometic rv rooftop.

Sound like the change-over valve on the heatpump is not switching. Could be the valve is stuck, or bad. Or the thermostat is bad and will not send voltage, or is sending voltage to your change-over valve.

(Some systems energize the CO valve to cool, while others de-energize the valve).

Usually the color coding for the thermostat wires on a heatpump are orange and yellow. The yellow wire usually energizes the compressor contactor, and the orange wire energizes the changeover valve. Now depending on what your system does in terms of energizing or not energizing the CO valve to invoke heating or cooling mode is not known. You can try jumping across the thermostat to see if the CO valve is working. Or you can even try placing the stat in heating mode and see if you hear that loud "Woosh" when you switch between heating and cooling modes at the stat.

What often happens is the cylinder inside the CO valve gets stuck, especially if the system has sat off for an extended time. By workign the stat from heating to cooling (reversing the porting on the CO valve) will cause the valve to free itself up.

If you cannot hear that woosh as the changeover valve switches between heat and cooling, it is possible the CO valve is bad, or there is an issue in the electrical or control side of your system. Such as a bad base or switching circuit in your stat, or control issues other places.

Sep 03, 2010 | Dometic Rooftop RV Air Conditioner

3 Answers

I am getting hot air instead of cool air from my heat pump when it is in the cooling mode.

The problem is in the thermostat wiring. Y1 on an air conditioner, brings on the cooling. On a heat pump, it brings on the compressor, which generally fails to heat mode. The O wire operates the reversing valve, which brings on cooling. If these wires are reversed, or not hooked up, you will not get cooling.

Jul 12, 2010 | Goodman CLQ36AR49 Air Conditioner

2 Answers

Weather King 10PJB18A01 heat pump. Compressor is working, however reversing valve is stuck in cooling mode. Need HEAT! Can this be fixed without replacing entire compressor?

yes it can be fixed with a reversing valve replacement or you can check if the solnoid on the reversing valve when in heat mode is energized if not then replace

Jan 06, 2010 | Weather King 10PJA4301AH Air Conditioner

1 Answer


The only unit I know that energizes the reversing valve in heat is Ruud or Rheem, All other makes energize in cool. When you switch from heat to cool htere is five minute delay. The y energizes the contactor on heat and cool. Make sure your tstat is ok. Rus Keep in touch.

Dec 15, 2009 | Air Conditioners

1 Answer

A/C starts, goes immediately to heat

Unfortunately, your rear unit is calling for heat. If you put the rear unit on heat pump mode, does it then cool?
moz-screenshot-2.jpgmoz-screenshot-3.jpgThe reversing valve is energized in the cool mode of these AC's. So there is no real way to bypass it. I would check the thermostat and the control board in the unit to make sure that the switches are set correctly.

In the service manual section of the dometic/Rooftop RV Air Conditioner section. I have posted service manuals for the Heat Pump and the Comfort Control.

Hope this helps,


Rate me please.

Jul 06, 2009 | Dometic Rooftop RV Air Conditioner

1 Answer

Reversing valve not switching over to air on heat pump. compressor will come on for about 10 minutes, then shut off. Hot air comes out vent.

Look for any refrigerant leaks - no or low refrigerant can cause problems in both modes. The unit may be going off on low suction.


The unit may be stuck in the heating mode.

Make sure the system is calling for the correct mode (cooling or heating) - some systems are auto, but if you can, select cooling since that is the requested mode. Check for power at the reversing valve inside the condensing unit. If power exists, then the reversing valve is stuck. It could also be the reversing valve solenoid coil, so make sure that isn't bad. There should be a strong magnetic field at the solenoid coil.

If you can hear the reversing valve clicking (moving), check the T-stat and make sure it will switch modes. Also check the reversing valve relay (those can be located in either the indoor unit or condensing unit).

May 25, 2009 | Ruud Matching Split Air Conditioner

1 Answer

LG PTAC acting strange in heat mode

I believe the problem in lies in the dual stage heat mode setup on the thermostat, but the unit going into defrost does make the unit act kinda strange. Even more so than other types of equipment. I would suggest hiring a licensed HVAC service technician if the problem cannot be resolved by yourself.

Dec 15, 2008 | LG LP120HED Wall/Window Air Conditioner

Not finding what you are looking for?
Air Conditioners Logo

Related Topics:

353 people viewed this question

Ask a Question

Usually answered in minutes!

Top Air Conditioners Experts

Mike Butler
Mike Butler

Level 3 Expert

6674 Answers


Level 3 Expert

1033 Answers

Dan Webster
Dan Webster

Level 3 Expert

8147 Answers

Are you an Air Conditioner Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides