OP
Is it possible to upgrade the A/C?
- Thread starter Bigmac
- Start date
Brianj5600
TJ Expert
Misting would probably work great in dry areas. Either on the condenser or after the evaporater or borh.
Would it be feasible to throw a breathable cover over the Jeep during daytime parking to get out the direct sun?
Louisiana here.... so I know your pain too.
Louisiana here.... so I know your pain too.
Another thread gave me this idea:
Plumb in valves on the heater core so you can bypass the heater core in the summer.
The heater core has hot coolant flowing through it constantly, regardless of the status of the HVAC system. Some of this heat inevitably escapes into the passenger compartment, and if the blend door doesn't seal perfectly, is mixed into the air conditioned air.
With 2 tees, a short section of hose, and 2 valves you could install a manual bypass. The tees connect the heater core inlet and outlet hoses with one valve in between. The other valve is placed inline with the heater core lines.
For heater use, the valve between the tees (bypass valve) remains closed, and the inline valve remains open. Coolant flows through the core as usual.
For A/C use only, the inline valve is shut and the bypass valve is partially opened.
It's not generally a good idea to simply deadhead the flow through the heater core because it serves as a bypass for the coolant to flow through before the thermostat opens. Flow through the engine block ensures that the engine warms up evenly, preventing stresses from uneven thermal expansion. That is why the bypass valve is needed. (However, too much bypass flow will reduce the effectiveness of the cooling system when the thermostat is open.)
Theoretically the flow through the heater core and bypass valve could be deadheaded once the engine is warmed up and the thermostat opened, assuming it remains hot enough for the thermostat to not shut. This would actually likely improve the effectiveness of the cooling system, as all of the flow goes through the radiator.
An alternative would be to find a thermostat that allows some bypass flow into the radiator when fully shut, but that would result in additional time required to warm up the engine.
Some high end cars actually block/bypass the heater core as a function of the "Max AC" setting.
Plumb in valves on the heater core so you can bypass the heater core in the summer.
The heater core has hot coolant flowing through it constantly, regardless of the status of the HVAC system. Some of this heat inevitably escapes into the passenger compartment, and if the blend door doesn't seal perfectly, is mixed into the air conditioned air.
With 2 tees, a short section of hose, and 2 valves you could install a manual bypass. The tees connect the heater core inlet and outlet hoses with one valve in between. The other valve is placed inline with the heater core lines.
For heater use, the valve between the tees (bypass valve) remains closed, and the inline valve remains open. Coolant flows through the core as usual.
For A/C use only, the inline valve is shut and the bypass valve is partially opened.
It's not generally a good idea to simply deadhead the flow through the heater core because it serves as a bypass for the coolant to flow through before the thermostat opens. Flow through the engine block ensures that the engine warms up evenly, preventing stresses from uneven thermal expansion. That is why the bypass valve is needed. (However, too much bypass flow will reduce the effectiveness of the cooling system when the thermostat is open.)
Theoretically the flow through the heater core and bypass valve could be deadheaded once the engine is warmed up and the thermostat opened, assuming it remains hot enough for the thermostat to not shut. This would actually likely improve the effectiveness of the cooling system, as all of the flow goes through the radiator.
An alternative would be to find a thermostat that allows some bypass flow into the radiator when fully shut, but that would result in additional time required to warm up the engine.
Some high end cars actually block/bypass the heater core as a function of the "Max AC" setting.
Most Oldsmobiles in the mid to late 70’s used a cable operated valve to block the water flow into the heater core.
The temp adjustment lever on the AC control operated two cables. One connected to the water valve and other was hooked to the blend door.
The temp adjustment lever on the AC control operated two cables. One connected to the water valve and other was hooked to the blend door.
This would not be hard to retrofit.
https://www.summitracing.com/parts/...agWW9f1F4z00oXmav3pzMhcv5fkcjaxRoCdMAQAvD_BwE
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This is a motorcraft valve that uses vacuum to active you can connect vac line to heater control so you only get hot water in air box during heat mode by passed in cool
OP
It's real amazing what the members of The forum can come up with sometimes. This seems like it would be simple to install, operate similar to factory, and doesn't break the bank. I can see how in theory this would make a difference but I'm not sure if it will be noticeable. I guess if it didn't do something it wouldn't exist on other vehicles.
I guess I'll have to let you all know!
You likely won't find a single point solution. The overall cooling effectiveness increase will come from a culmination of several things. Get the heat out of the air box when the heater isn't needed. That will slow down the amount of radiant heat off the surfaces of the air box. Pull the dash and get some insulation on the firewall like the DEI Lava Shield. Carry that down to the floor board. Add some heat shield over the exhaust on the passenger side above the factory heat shield. Wrap the exhaust on that side with exhaust wrap. Insulate the rest of the interior sheet metal. Insulate the top. Pull the door panels and insulate inside the door on the outer skin. You have a black rig, it is going to make a lot of heat in the sun and that transfers to the inside.
That heater valve? I wouldn't expect it to make more than a 1 or 2 degree difference. Insulating the insides of the doors would make more of a difference if I had to guess.
So I recently thought of this thread and thought I should add to it:
The explorer 11-blade fan and HD fan clutch actually seems to have dropped the A/C temperature noticeably, particularly at the highest blower motor speeds when the vehicle is idling or moving at low speeds. The change isn't very large, but I can stay cooler on warm days. The hotter the outside temperature, the more noticeable the difference.
By increasing the airflow across the condenser, you effectively increase the amount of heat rejection. Assuming the A/C was already working properly, you are not going to condense any additional refrigerant. The condensed refrigerant should already be flowing out as a liquid. But the additional airflow provides an additional amount of subcooling, lowering the condensed refrigerant's temperature before it enters the orifice tube, resulting in a colder low side/evaporator temperature. The effect will be most noticeable on the hottest days.
It is possible to overcool the condenser too far, to the point that high side system pressures drop and less fluid is forced through the orifice tube. But in normal operating conditions this will not be a problem.
To do this mild upgrade you need two parts:
https://www.amazon.com/dp/B000C3BB0I/?tag=wranglerorg-20https://www.fordpartsgiant.com/parts/ford-fan-asy_f87z-8600-ea.html
The fan and clutch are based off the Ford Explorer and directly bolt in. You may need to pick up four small metric bolts for the fan clutch to fan attachment. If you cross reference the parts, specifically look for the 11-blade fan for best performance.
The explorer 11-blade fan and HD fan clutch actually seems to have dropped the A/C temperature noticeably, particularly at the highest blower motor speeds when the vehicle is idling or moving at low speeds. The change isn't very large, but I can stay cooler on warm days. The hotter the outside temperature, the more noticeable the difference.
By increasing the airflow across the condenser, you effectively increase the amount of heat rejection. Assuming the A/C was already working properly, you are not going to condense any additional refrigerant. The condensed refrigerant should already be flowing out as a liquid. But the additional airflow provides an additional amount of subcooling, lowering the condensed refrigerant's temperature before it enters the orifice tube, resulting in a colder low side/evaporator temperature. The effect will be most noticeable on the hottest days.
It is possible to overcool the condenser too far, to the point that high side system pressures drop and less fluid is forced through the orifice tube. But in normal operating conditions this will not be a problem.
To do this mild upgrade you need two parts:
https://www.amazon.com/dp/B000C3BB0I/?tag=wranglerorg-20https://www.fordpartsgiant.com/parts/ford-fan-asy_f87z-8600-ea.html
The fan and clutch are based off the Ford Explorer and directly bolt in. You may need to pick up four small metric bolts for the fan clutch to fan attachment. If you cross reference the parts, specifically look for the 11-blade fan for best performance.
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You can order the 7 blade fan and heavy duty fan clutch ( at one time the seven blade was a option installed by dealer for high temp areas )
Your not most likely won’t overcool condenser because at that point low pressure switch will drop out until head pressure rises
The OEM 7-blade fan is also a good option, and would work with an OEM HD fan clutch. Unfortunately the OEM 7-blade fans are quite rare.
The Explorer 11-blade fan and Explorer HD clutch move significantly more air than the 5 or 7 blade TJ designs, but the 7 blade is still a good upgrade over 5.
Derale still makes one , when I get a chance will look up part number and add to this thread
Ok correction the Derale fan (steel) is a six blade but pitch is designed for 500 to 750 cfm additional part # 17918
Hayden HD fan clutch #2771
In testing the Derale blade I achieved at idle 250 cfm over 5 blade
This weekend sitting in traffic at 90 outdoor temp A/c was blowing 39 degrees on second speed
What is the downside to the 6 blade fan? I assume the 5 blade, with the offset blade is there to reduce noise? Is the 6 blade noticeably louder?