I see where a lot people do away with the heater valve, run the hoses straight to the heater core and plug the vacuum line. Doesnt that make the heater on all the time? (hot coolant running through the core all the time) Does it affect A/C operation? My heater valve is cracked, If I can do without and run it straight it would be simple. 95 XJ 4.0.

 

Nope.
The heat is controlled by the blend door. It doesn't affect the ac ops. It is a very simple job to do you can do it in 2 different ways. The first and recommended way is to just but some bulk hose and replace the entire hose. Or you can put in a barbed fitting and a couple of hose clamps.

 

I put both of my Jeeps back factory when I had to replace mine.

It's not a big deal. Everything works as it should.

If it was better the other way, then they would have done it like that.

The people that eliminate the valve are the first ones to holler that their A/C won't blow cold when warmer weather hits, or that their defrost/defog doesn't work right when its colder.

 

If you think about. They did do it without the valve. If I'm not mistaken they stopped putting it on in 95 or 96.

 

Even before that I believe... My 93 didn't come with one

 

My '96 has one. The AC runs a couple degrees colder with it in place, which I why I replaced it. Might be an insignificant difference if your A/C is working 100%. Mine is showing it's age, lol. It's a $10 part.

 

Yes it was removed due to failure rate and it kinda explodes coolant everywhere. Late model XJs just rely on the blend door. The A/C core, however, is always inline. (not sure what that part of the AC is called). Radiant heat and a bad seal will cause your AC to be less effective

 

I removed the valve in mine since the cheap china junk started leaking. Since i removed it i always have hot air blowing out the vents if the fan is on. Before i could get nice cool outside air on the vent setting and heat when set to heat, the ac is removed and never worked. Im sure i have other problems in the hvac system but i will be putting the valve back in

 

If you have heat coming in either you blend door isn't closing all the way or the seals are bad on the blend door. Personally I have never had heat coming in after removing the valve. But that is just my experiences with them.

 

i replaced mine and found that my original issue was actually due to leaky vacuum line that terminates into firewall. if i moved to florida, I'd get rid of the whole mess!

 

I removed mine. It snapped apart moving the heater hoses so I could get to the spark plug. I got a whole hose on there. As a temporary fix I shoved pvc pipe in there

 

I believe '97 and up the factory eliminated it.

 

OK. I wasn't 100% when they stopped putting them in. Because my 95 didn't have one and didn't know if the po removed it or not.

 

Sorry to dig up an old-ish thread...didn't want to start a new one when we could just add more info to an old one!

I have a '95 and I DO have a heater control valve. It is leaking... pretty good too. About a drip every second... no wonder my coolant keeps disappearing.

Could this be why my heat and a/c are not very stong? I feel like my a/c especially used to be much stronger.

Help!

 

Faulty blend door/seals and/or faulty a/c/low refrigerant could lead to weak a/c performance.