I got 98 accord that all the sudden blow hot air only. The hot/cold control **** is on cool side and still blow hot air with ac on or off. I was thinking climate control unit going. Any suggestions guys? Thanks.

 

Did you check the HVAC unit for any codes?

Next I would inspect the heater control valve and cable.

 

Took to awhile to find the heater valve I think the problem is the cable I won't move so the valve is stuck on heat side or could the the motor controlling the cable. Is this something repairable by novice? Seems lot of work getting to the cable.
Thanks

 

Again, there is a "self test" function on the HVAC unit that you can do that will help detect any issues.

With the key on, if you turn the heat **** and the cable is not moving then I would start by testing the air mix motor.

 

When that happened on mine, I had to replace the AC controller in the dash. You can find videos how to do it on YouTube. I takes about 10 minutes to get it out. I got a replacement at an open-air used auto parts mall (salvage yard) for about $20. Some salvage yards give a 30 day warranty so if it doesn't work, you can take it back.

 

As mentioned, check water valve... Honda Automotive Parts if hose #4 is hot valve is not working, either valve is stuck open or there is a valve control problem. 94