What is your question?
·
·
What is your question?
I have a 2000 Chevy Express 3500 LS 15 passenger van with 7.4l Van has Front and Rear zone control for HVAC I've had the van for a little over a year and purchased from a good friend with 87k. Front air blew cold all last year, but noticed that defrost didn't seem to de-fog the windows over the winter. Now I know why. The front vents blow luke warm air. The rear controls function as they should and blow cold. When I only have the front A/C turned on the compressor cycles on/off and the system blows warm. As soon as i turn on rear A/C the compressor turns on and runs as it should. Front vents remain warm. I found what I believe is the hose that hooks to the canister. It has an 'L' connector (not T per posts) and seems to sit snug. Would the rear A/C function if this had a leak? Are they tied together. I haven't had the opportunity to search for the 'blend door' and noted that this may also be the issue. A follow up question: Are there 2-closed systems with refrigerant? Thank
What makes this problem better or worse?
***Engine 7.4*** Wasn't listed above
How long has your 2000 Chevrolet Express 3500 had this problem?
since spring
1 Reply
I'm thinking you have a problem with temperature blending in the front. OR, you could have an issue with the front system icing over due to a cycle switch or high pressure cut off switch issue. The good news: your compressor works and the system in general works since your rear air works! The bad news -- you have a front air problem that you need to isolate. Check temperature blend issues first; make sure it's changing from hot to cold. Also mode doors: dash vents instead of floor or defrost. To my knowledge, you have a single system with 2 evaporator cores. Front and rear.
Hi DaveJM! I appreciate your reply. Having the compressor running is a huge plus. The air vent acuator for directing air to either windshield, front seats and or feet is functional. With A/C running and switch to heat I get heat from front vents and will 'cool off' when I turn the knob back to the cool setting, but blowing unconditioned air. I know this for certain because the windshield will not de-fog when on defrost. Hmm, so perhaps the blend door isn't directing air flow over evap coil? If it's pushed the other way wouldn't it be blowing HOT air out of the vents at all times? I may have some time in the coming 5-6 days to dig deeper. Is the blend door on this 3500 under passenger side dash like I've read about for a few other Express Vans? Thanks again for the help!!!
Sorry for the delay in response. Yes, it could be a temperature blend door issue, not moving all the way to "cold" -- but it could be the door or evaporator case itself, if it's not the little motor that turns the door. Hard to say. The blend door may or may not be accessible without accessing the dash, worth some hands on investigation.
Hi DaveJM! Sorry for the VERY delayed response. I was finally able to get out to the van and here is what I discovered. I pulled the lower part of the dash off (Passenger/Drivers side) and able to see one of the blend door actuators on the passenger side but not the drivers side (It may be buried). I believe that there is a second but cannot find a schematic to confirm. I've tried AutoZone and other 'DIY' sites and the second spot placement isn't noted. I did cross reference a few other actuators and came up with the following on dormans website: https://www.dormanproducts.com/gsearch.aspx?year=2000&make=Chevrolet&model=Express%25203500&origin=YMM&parttype=Air%2520Door%2520Actuator&position=Main There is at least one of the 'round' style actuators near the above mentioned actuator. This may be the culprit, but keeping thinking that there is a second because of some of the forums that I have read. Interestingly this happened: I started the van and turned on the AC. While looking at the actuator, I turned the temp gauge hotter and could see the actuator move. I put my hand up to the far passenger vent (window) and it was blowing cold air. The center vents and drivers side blowing mild temp air like before. I moved the temp control a couple more times and the same thing happened. I now believe that there is a second actuator, but cannot seem to locate. What I find interesting that is that this is a dual climate system, BUT not left/right, but front/back. Do you have any schematics or locations to get schematics. I'd pop the top part of the dash off if it was a quick look-see to confirm additional actuators, but at 45-1hr to drop the steering column, air-bag, radio, etc. I'd prefer to have confirmation as not to waste time. Plus, I always get a bit sketchy around air bags. Thank you again for your help! Ed
ED what was the fix for this? i have the same problem...
It’s definitely an odd problem since I’ve searched for hours on the web. Nobody seems to have an answer. System full of 134, compressor running. Beer can cold suction line from dashboard. Rear vents blowing 40 degree air. Front passenger one vent blows 27 degree air, rest of dash vents blowing 70 degrees. Velocity seems normal. Outside air 100 degrees. I never viewed the actuator when the ac worked correctly. But the actuator switch from heat to cool normally it seems. Turned damper manually with actuator off, pneumatic actuators operating. No answer nowhere on YouTube. Did cut bottom of housing off exposing the heater core and damper. I know this is an old topic, but I just wanted to chime, maybe shine a bit. No cabin air filter. If the evaporator was that dirty I would expect s colder return or suction line.
I appreciate you and all others who have chimed in on the subject. Hotter than you know what this summer and I am still slugging along with no AC. I do not put aot of miles on the van and typically use 2-3 times per month. I grin and bear the summer, but this year it's getting to me again. Any traction on anyone's end?
WOW - can't believe I didn't see this post 5-years ago. Unfortunately still no luck, but not a high priority. HOWEVER! THIS SUMMER HAS BEEN BRUTAL and still would love to get this solved