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EcoCivic · 03-09-2020, 09:04 PM

I thought of another idea to improve the AC's performance and efficiency: Move the condenser to the roof and stand it up straight so it gets the best possible airflow. I can think of the following advantages of doing this:

1. Better AC performance and longevity. The condenser wouldn't be right against the hot radiator and its airflow wont be blocked by the radiator, trans cooler, bumper cover, and grill. The grill could also be blocked off more without overheating the engine or causing a problem with the AC, which would help offset the aerodynamic penalty a little.

2. Improved engine cooling. The condenser wouldn't be blocking airflow through the radiator or preheating the air flowing into the rad, improving engine cooling.

3. The condenser would be way less susceptible to damage. It couldn't be damaged by road debris or by a front end collision, which is arguably safer too since there's significantly less chance of flammable refrigerant being released into the engine compartment.

4. Less heat soak. The intake air, piping, manifold, and fuel system wouldn't be heated up by hot air coming off the condenser, which is better for performance.

5. Cooler interior. The engine compartment and therefore the firewall and the floor of the car will stay cooler and not heat up the interior as much.

6. The electrical components as well as plastic and rubber parts in the engine compartment would last longer from not being exposed to the heat from the AC condenser, likely the paint on the hood and fenders would last longer too.

The disadvantages would be:

1. Increased frontal area and therefore increased drag, although this could be largely eliminated by mounting the condenser to a folding frame so it can be laid flat against the roof on cool days when the AC isn't needed and during the cool seasons.

2. Some people wouldn't like the way a roof mounted condenser looks, but the heck with their opinion.

3. Increased electrical draw at idle and low speeds. The condenser would need its own fans since it would no longer be able to share the radiator's fans, which would use more power. However, the extra amp draw is less than what you may initially think because the radiator's fans would only need to cycle to keep the engine cool, they would not need to run constantly whenever the AC is on to keep the condenser cool like they would if the condenser was in front of the radiator.

4. The stock AC lines obviously wouldn't be long enough, so custom lines would need to be made to connect the condenser to the compressor and filter dryer.

5. Slightly more weight due to condenser mounting hardware, longer refrigerant lines, and increased refrigerant charge.

03-09-2020, 09:04 PM	#89 (permalink)
EcoCivic Master EcoModder Join Date: Jul 2017 Location: Memphis, Tn Posts: 463 Thanks: 320 Thanked 107 Times in 81 Posts	I thought of another idea to improve the AC's performance and efficiency: Move the condenser to the roof and stand it up straight so it gets the best possible airflow. I can think of the following advantages of doing this: 1. Better AC performance and longevity. The condenser wouldn't be right against the hot radiator and its airflow wont be blocked by the radiator, trans cooler, bumper cover, and grill. The grill could also be blocked off more without overheating the engine or causing a problem with the AC, which would help offset the aerodynamic penalty a little. 2. Improved engine cooling. The condenser wouldn't be blocking airflow through the radiator or preheating the air flowing into the rad, improving engine cooling. 3. The condenser would be way less susceptible to damage. It couldn't be damaged by road debris or by a front end collision, which is arguably safer too since there's significantly less chance of flammable refrigerant being released into the engine compartment. 4. Less heat soak. The intake air, piping, manifold, and fuel system wouldn't be heated up by hot air coming off the condenser, which is better for performance. 5. Cooler interior. The engine compartment and therefore the firewall and the floor of the car will stay cooler and not heat up the interior as much. 6. The electrical components as well as plastic and rubber parts in the engine compartment would last longer from not being exposed to the heat from the AC condenser, likely the paint on the hood and fenders would last longer too. The disadvantages would be: 1. Increased frontal area and therefore increased drag, although this could be largely eliminated by mounting the condenser to a folding frame so it can be laid flat against the roof on cool days when the AC isn't needed and during the cool seasons. 2. Some people wouldn't like the way a roof mounted condenser looks, but the heck with their opinion. 3. Increased electrical draw at idle and low speeds. The condenser would need its own fans since it would no longer be able to share the radiator's fans, which would use more power. However, the extra amp draw is less than what you may initially think because the radiator's fans would only need to cycle to keep the engine cool, they would not need to run constantly whenever the AC is on to keep the condenser cool like they would if the condenser was in front of the radiator. 4. The stock AC lines obviously wouldn't be long enough, so custom lines would need to be made to connect the condenser to the compressor and filter dryer. 5. Slightly more weight due to condenser mounting hardware, longer refrigerant lines, and increased refrigerant charge.