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Waggie
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That is reasonably normal for stopped in traffic, max I've seen is circa 220F, again while stopped motor running. I do not see anything beyond 210F while moving, even with a big tow load and major elevation gains.

Maybe the 180 Tstat guys will chime in here.
 

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Was in traffic yesterday, mid-70s & windows open. Saw 215+ F at stoplight. Is too hot but factory does not turn fan on yet.

Anyone know of an aftermarket device that can turn fan on earlier, say 197F. Personally get bothered by temps over 200F.

ps at 215F the guage had not yet reached 1/2.
The aftermarket device is called COLDER THERMOSTAT if you want a mechanical solution. Most thermostats these days are 195, 180 or 160 deg F. Probably the Jeep has a 195 deg F unit.

I have a 160 deg F thermostat on the Subaru and keeps the engine temps around 180 deg. (I have a dedicated gauge for that).

Fan operation can also be controlled at the level of cooling fan relays (which on a Subaru Legacy fail every 2-3 years); thermistor (that detects the temperature and opens the switch) and the ECU himself.

You can also turn on the heat in the cab or engage the AC in the cab - both operations actually open a new pathway for the cooling fluid to go through. One goes to the circuit that will blow hot air in the cab (probably undesirable) and the other method engages the A/C compressor which itself needs to be cooled but as the engine coolant exchanges heat with the A/C juice there will be an overall reduction in your engine coolant temps (at least on Subarus).

But I would not worry about it. Remember, 195 deg thermostats are needed to control emissions.
 

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The aftermarket device is called COLDER THERMOSTAT if you want a mechanical solution. Most thermostats these days are 195, 180 or 160 deg F. Probably the Jeep has a 195 deg F unit.

I have a 160 deg F thermostat on the Subaru and keeps the engine temps around 180 deg. (I have a dedicated gauge for that).

Fan operation can also be controlled at the level of cooling fan relays (which on a Subaru Legacy fail every 2-3 years); thermistor (that detects the temperature and opens the switch) and the ECU himself.

You can also turn on the heat in the cab or engage the AC in the cab - both operations actually open a new pathway for the cooling fluid to go through. One goes to the circuit that will blow hot air in the cab (probably undesirable) and the other method engages the A/C compressor which itself needs to be cooled but as the engine coolant exchanges heat with the A/C juice there will be an overall reduction in your engine coolant temps (at least on Subarus).

But I would not worry about it. Remember, 195 deg thermostats are needed to control emissions.
I would think turning on the A-C would increase the coolant temperature on any vehicle. Please explain how running the AC will reduce coolant temps. Thanks
 

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I would think turning on the A-C would increase the coolant temperature on any vehicle. Please explain how running the AC will reduce coolant temps. Thanks
Turning on the ac would increase coolant temp because the hot refrigerant needs to be cooled through the condenser which is in front of the radiator, although the fan needs to come on so it would accomplish turning the fan on at least.
 

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215F is relatively cool for todays engines, don't worry about it. You may just be a bit paranoid. You could try to put a lower T Thermostat in, but the lower temps will affect how much and when fuel is squirted, so your performance is not going to be optimum. I think your cats will run hotter on the richer mix and will burn out sooner, and there would be no affect on the reliability of other components. So if your goal is long life or reliability, you may be shooting yourself in the foot.

I think your best option is to add auxiliary cooling fans and turn them on in stop-go traffic.
 

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I've often seen it.
 

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Oh I will explain and prove it no worries. Give me about 2 hrs. But if you think that the compressor runs all the time you are wrong. Just like the fridge it cycles as for the refrigerant to not freeze the pipes/clutch. The heat exchange is actually different than how you think
 

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2017 Summit
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Damn owner's manual must have it wrong again. :lol:

"This light warns of an overheated engine condition.
As temperatures rise and the gauge approaches
H,
this indicator will illuminate and a single
chime will sound after reaching a set threshold. Further
overheating will cause the temperature gauge to pass
H,

the indicator will continuously flash and a continuous
chime will occur until the engine is allowed to cool.
If the light turns on while driving, safely pull over and
stop the vehicle. If the A/C system is on, turn it off."
 

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Oh I will explain and prove it no worries. Give me about 2 hrs. But if you think that the compressor runs all the time you are wrong. Just like the fridge it cycles as for the refrigerant to not freeze the pipes/clutch. The heat exchange is actually different than how you think
The compressor does not run all of the time but the heat it removes for the cabin has to go somewhere.
 

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Turning on the ac would increase coolant temp because the hot refrigerant needs to be cooled through the condenser which is in front of the radiator, although the fan needs to come on so it would accomplish turning the fan on at least.
That's what I was saying "I would think turning on the A-C would increase the coolant temperature on any vehicle. Please explain how running the AC will reduce coolant temps. Thanks"
 

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Oh I will explain and prove it no worries. Give me about 2 hrs. But if you think that the compressor runs all the time you are wrong. Just like the fridge it cycles as for the refrigerant to not freeze the pipes/clutch. The heat exchange is actually different than how you think
No need to prove it for my sake. I already know for a fact that running the A-C will increase the coolant temperature. Running the heater will help reduce the coolant temps...
 

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Was in traffic yesterday, mid-70s & windows open. Saw 215+ F at stoplight. Is too hot but factory does not turn fan on yet.

Anyone know of an aftermarket device that can turn fan on earlier, say 197F. Personally get bothered by temps over 200F.

ps at 215F the guage had not yet reached 1/2.

Why would you want your fans to come on earlier? The engineers designed the engine to run at certain temps. So no that is not "too hot". Just drive the Jeep and enjoy :thumbsup:
 

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If engine temps are at 215, how does a 180 thermostat keep things cooler than a 195? Won't both thermostats be open at that temp?
 

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Turning on the ac would increase coolant temp because the hot refrigerant needs to be cooled through the condenser which is in front of the radiator, although the fan needs to come on so it would accomplish turning the fan on at least.
I agree with this. With the caveat that my experience is on Subaru, not Jeep, we are talking two separate circuits here. Hot refrigerant and Hot coolant are two different circuits. The condenser is in front of the radiator, there is a cold side and a hot side to the HVAC system. But that is a parallel system to the the engine coolant.

I would think turning on the A-C would increase the coolant temperature on any vehicle. Please explain how running the AC will reduce coolant temps. Thanks
I am trying.

215F is relatively cool for todays engines, don't worry about it. You may just be a bit paranoid. You could try to put a lower T Thermostat in, but the lower temps will affect how much and when fuel is squirted, so your performance is not going to be optimum. I think your cats will run hotter on the richer mix and will burn out sooner, and there would be no affect on the reliability of other components. So if your goal is long life or reliability, you may be shooting yourself in the foot.

I think your best option is to add auxiliary cooling fans and turn them on in stop-go traffic.
I think the user may be a bit paranoid but I think a Colder Thermostat would serve him better.

The compressor does not run all of the time but the heat it removes for the cabin has to go somewhere.
Actually heat is NOT removed from the cabin. Cold air is pushed through.

That's what I was saying "I would think turning on the A-C would increase the coolant temperature on any vehicle. Please explain how running the AC will reduce coolant temps. Thanks"
No need to prove it for my sake. I already know for a fact that running the A-C will increase the coolant temperature. Running the heater will help reduce the coolant temps...
But let's keep it very simple. What I am saying here is that at least on Subarus when I turn on the AC, the engine temps go down because it will force the fans to run at all times. On a properly working system. They recommend to turn of the AC so that the load on the engine is diminished because ultimately the AC compressor is belt driven.

Here's pictures:
 

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(A-C 101)

Actually, the A-C system removes heat and moisture from the cabin air and the air is returned "cooled".

A little more explanation:

Air conditioners remove heat from indoor air and transfer it outdoors. Cool air is then returned to the cabin. The cycle continues until the indoor air reaches the “set point,” or the desired temperature on your thermostat. Cool refrigerant gas is pumped into the compressor where it is—you guessed it—compressed, which heats the refrigerant. The hot refrigerant gas then passes through the condenser coil, where it is cooled, and changes from a gas to a liquid. This liquid runs through an expansion device, which further cools the gas as it enters the evaporator coil. This cooler gas collects moisture (in the form of water beads on the outside evaporator coil surface) and heat from the air to be cooled. The cooled air is then returned to the cabin and the process repeats until the cabin temperature reaches the desired set point.
The compressor pumps and heats the refrigerant, increasing the temperature and pressure of the gas. The hot gas passes through coils, loses heat and condenses into a liquid. This liquid runs through an expansion valve and evaporates to become cold, low-pressure gas. The cold gas passes through a set of coils that cools the air. A fan blows the cool air into the cabin.
 

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Really don't want to get in the middle of this........ but if you turn the A/C on while sitting in an idling WK2 that has coolant temps at 220*+ the fans will immediately turn on and the coolant temperature will decrease! Thats the way your WK2 works, as designed by the engineers who built it.

If you don't believe me, go out and try it in your driveway. :cool:
 

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Really don't want to get in the middle of this........ but if you turn the A/C on while sitting in an idling WK2 that has coolant temps at 220*+ the fans will immediately turn on and the coolant temperature will decrease! Thats the way your WK2 works, as designed by the engineers who built it.

If you don't believe me, go out and try it in your driveway. :cool:
My apologies to the OP, we sure highjacked your thread.

This is not a reliable test. The ambient temperature will play a big part in the results.

If the A-C condenser is mounted in front of the radiator, the fan will pull "hotter" than ambient temperature air (with A-C on) across the radiator and the engine cooling will be less efficient.
 

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My apologies to the OP, we sure highjacked your thread.

This is not a reliable test. The ambient temperature will play a big part in the results.

If the A-C condenser is mounted in front of the radiator, the fan will pull "hotter" than ambient temperature air (with A-C on) across the radiator and the engine cooling will be less efficient.
Your missing the point, with coolant temps over 220* an idling WK2 will kick on the fans and lower the coolant temperature. All the time, every time!
Doesn't matter what the ambient temp is.
 

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If engine temps are at 215, how does a 180 thermostat keep things cooler than a 195? Won't both thermostats be open at that temp?
Now that there is a good point... start thinking auxiliary fans.... :)
 
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