Boggy after pull down on C10 at 95 F and 55 mph is 45 recirc/max and 55 outside air w/ R12 with full Phoenix sun
Hotrodac
71 Chevrolet C/10-Pressures good / air only cool?
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ice-n-tropics
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Re: 71 Chevrolet C/10-Pressures good / air only cool?
Condenser is nice and clean. You're seeing the iphone get confused and go out of focus on the fins. I will double check the drier. My Dad installed that so I cannot confirm the direction is correct. Thank you for the insights! I haven't been with the truck all weekend but will be tonight so I can check out some of these great tips. Gracias!
Phillip
Phillip
Re: 71 Chevrolet C/10-Pressures good / air only cool?
Sorry, is this a question or a statement? I couldn't follow.ice-n-tropics wrote:Boggy after pull down on C10 at 95 F and 55 mph is 45 recirc/max and 55 outside air w/ R12 with full Phoenix sun
Hotrodac
Re: 71 Chevrolet C/10-Pressures good / air only cool?
One thing to remember is the heat of the air inside a vehicle can influence your AC performance. If the ambient air in the vehicle is hot, it will make the Ac seem not cold enough. Sometimes your vehicle must run for 20 to 30 minutes before the vent temps come down. This is because the Ac system takes the inside air, cools it and dehumidifies it. If the ambient air inside the vehicle has a high amount of humidity, your system will have to condition the latent heat before it can condition the sensible heat. So if this system is putting out 52* (for example) at the vents, when you drive 20 or 30 minutes, the vent temps may and will probably drop. I hate to use rules of thumbs but if your vent temps are 30 * less than the air in front of the condenser, you may not even have a problem. Also, all of my vent temps are spec'ed out at the right hand vent 2000 rpm. POA pressures are 28 to 31 psi. You're looking at a 45 year old vehicle. The seals around the evap can be leaking, duct work can be leaking, etc.
Re: 71 Chevrolet C/10-Pressures good / air only cool?
These are all great things to keep in mind. Thank you. I have installed all new ducting and gone in and insulate/taped up any leaks in the air box. You're right, maybe I'm comparing this system to my newer systems, however my 70 chevelle has the same basic system and is blowing around 39-40 on R-12 with everything being the same. Last time I checked the ducts on the truck it was after a 25 mile drive. If none of these suggestions prove positive I might just have to live with the AC not being as good as the Chevelle's system. For whatever reason.
Re: 71 Chevrolet C/10-Pressures good / air only cool?
It's possible your TXV is not exactly the same as the Chevelle. Disconnect the blower motor and note the PSi on the POA. Do the same for the Chevelle. Is the condenser the same size on both vehicles? Are you using the same compressor? What about air flow across the condenser? Did you try misting the condenser with a hose and see if performance changes? There are a lot of variables to be considered. Also, is the TXV bulb mounted correctly on a clean surface? How about the diameter of the clutch pulley? Are they the same? Glass area of the vehicles and insulation valve of the headliner? Color of the headliner? Just mentioning some variables.
Re: 71 Chevrolet C/10-Pressures good / air only cool?
All great points Doug!Dougflas wrote:It's possible your TXV is not exactly the same as the Chevelle. Disconnect the blower motor and note the PSi on the POA. Do the same for the Chevelle. Is the condenser the same size on both vehicles? Are you using the same compressor? What about air flow across the condenser? Did you try misting the condenser with a hose and see if performance changes? There are a lot of variables to be considered. Also, is the TXV bulb mounted correctly on a clean surface? How about the diameter of the clutch pulley? Are they the same? Glass area of the vehicles and insulation valve of the headliner? Color of the headliner? Just mentioning some variables.
Re: 71 Chevrolet C/10-Pressures good / air only cool?
Next road test, pull it down a gear and get the cruising RPM up - then check the vent temp.
Re: 71 Chevrolet C/10-Pressures good / air only cool?
Just wanted to update this post. Turned out to be my Heater Control Valve was leaking water by it. I have a vacuum valve that is setup properly but I must have a small vacuum leak as it is not pulling it shut all the way. I added a couple zip ties and manually shut off the water. Now the air is perfect. Blowing 41* on a 100* day. Pretty happy camper now. Cannot believe what about 8-9* change in vent temp does to cabin temps.