Honda Car Forum

the ac compressor was removed now im wondering if i have to have some of the ac components for the heat to work or if something else might be wrong causing my heat not to work.

Check the level of the radiator fluid. If it's full, try having the thermostat changed. If that doesn't help, you may need a new heater core.

it does not really have anything to do with the a/c but you do need to make sure you have the proper components like the heater control valve and a conected heater core.

You have 0 heat or some heat? Check for full coolant... then...If you have good flow through your heater core (towards the firewall 2 lines going in 1 in and 1 return) you should pull good heat. the only other thing that ties into the heat is your heater control valve which limits the amount of coolant flowing through the heater core controlled via vacuum on the heater switch.As the engine warms up you should feel the lines going to the heater core warm up, you may not have good flow through the heater core if you still feel no heat, may need flush or replacement.

Your question is slightly on the incomplete side do to a lack of info on your part. So, it is a little difficult to answer.The simple answer is NO. Having the A/C compressor removed will not cause the heating system to stop working unless a fuse was blown in the process of de-installation.There are two possible problems other than a blown fuse that could be your problem. 1. Heater fan not working.2. The heating system is not getting engine coolant flowing through the heater core. Or air ducts are blocked/closed. 1.If your heater not working because the heater fan is not blowing air through the vents then you need to do the following:•First check for blown fuses ( Fuse No.19) under drivers side dashboard•Unplug the two wire connector off the heater motor. If your sitting in the passenger seat the heater motor is located under the dashboard and behind the glove box to the far right. •Turn on the ignition switch, and turn the heater fan control selector to the high position. With a volt meter or "check light" measure voltage between the blue/white (wire colors may very depending on year of CRX) wire and the body/chassis ground. If you have battery voltage (around 12.5 VDC) then test between the blue/white wire and the blue/black wire on the connector for battery voltage. If it also has battery voltage then this is a sure indication that your heater fan motor is bad and needs replaced. •If you did not measure voltage between the blue/white wire and the blue/black wire on the connector but you do when measuring between the blue/white wire and the body/chassis ground, then you need to check the blue/black wiring between the heater motor and the heater fan selector switch, because there is a broken connection or the selector switch is bad itself.2. Possibility two is the heating system is not getting engine coolant flowing through the heater core. Or air ducts are blocked/closed. You feel and hear air blowing out of vents but the air is cool even with the engine fully wormed up.•Check engine coolant level and make sure it is full. •Problem with the hot/cold air selector system. The selector dial should turn but with some resistance. Check the cable connected to it after removing the controller assembly from the dash. And also check the other end of the cable under the hood were the cable connects to the heater valve located next to the fire wall. Cable may be broken, try moving it by hand from one end while someone else checks for movement on the other end.•Clogged/closed heater valve. Turn heater selector knob to the fully hot position. Start the car and let run until fully wormed up. While it is running go under the hood and find the to black RUBBER hoses ( about an inch in diameter) coming out of the firewall from the inside the car. They will both be located within a couple inches from each other. If one or both of the hoses are cold to the touch and the car does not have over heating problems and heats up to normal temp. Then your heater control valve is closed or plugged. It is also possible that the heater core is totally plugged as well. IMPORTANT: Let the engine completely cool before moving to the next step. Disconnect the upper hose from the heater core at the firewall. This is the hose without the heater control valve. Find a small gallon jug/container and position is so it will catch the coolant from the heater core. Have someone start/run the engine for about 30 seconds and check to see if coolant is flowing freely into the container. You may want to rev the engine slightly to see if you have better flow if it is not flowing. It should feel the container up in less than a minute if all is well.•Problem with the outside/inside air select system. There are two very different designs that Honda uses for this system. One is a very simple cable connected system that you slide the selector from left to right . The other is a more complex electrical pushbutton system that drives small electric motors that move a big flat plate inside the air ducts to reroute the air accordingly. Chances are your system is the complicated pushbutton type. •However you can do a simple check of both of these systems by looking and listening for changes in the system inside under the dashboard. If all is working correctly you should see the small motors or cable moving the heater plate through it’s different positions while making changing to it from the dashboard selector switches/buttons. •Externally clogged ( with leaves, pine needles, bugs, drug money, etc.) A/C evaporator located next to the heater core inside the car under the dashboard. To get to it you need to disassemble the ducting behind the glove box. To do this you must disconnect the heater hoses from the heater core under the hood and any A/C lines as well as removing the glove box.•Clogged heater core externally or internally ( if by chance you have a green smelly puddle in your passenger side floor board then your heater core has a crack in it and needs replaced )•Engine thermostat not workingI hope this helps. Give me some thumbs up ok.

Dear David,

I have a JDM 1991 Honda City which basically has the same heat control system with AC. ever since i bought the car, AC works great but no heat at all. i had a closer look at this, the air mixing door at the HVAC system works fine, and so does the other side of the cable which goes to the heater control valve, however the 2 horses coming from the firewall, one goes the heater control and the other goes to the manifold, the one that goes to the manifold is disconnected from the manifold itself and its just hanging free and my question 1 is if it is disconnected, how come coolant is not leaking? and when i had a look at the heater control valve, only one horse is connected and the other end of the valve is just free, i dont know where the other horse or where does it connect. and another thing is, this is not a vacuum controlled heater valve, this is done by a cable, if that is so like all the hondas, why is there a 2 wire connection goes to the heater control valve apart from the cable? is there some sort of a sensor in the heater control valve? please help me on this, i need to get the heater working again. thank you