Fan

[Pmcmath]

So had my def header replaced for the second time and they found my lines to be crossed. The flipped them around and it changed my temp gauge readings. It used to go up to about 210 and then the fan would kick on and run till it cooled.to around 170. Now my gauge stays around 190 and the fan runs constantly and will cut off for about 3 to 10 seconds and turn right back on. Has anyone else had the issue? I traveled for 3 hours and out of that it probably ran 2 hours 50 minutes.

[Drv]

I would say you need to reach out to FCCC, as what you are describing does not sound like "normal" after DEF Head replacement. The behavior of your fan prior to replacement was and is consistent with how my unit acted before and after DEF Head replacement.
I had to have mine changed out due to total failure this past July.
Im assuming nothing dramatically changed in your overall engine load, speed and ambient temps were similar pre and post DEF Head replacement?

[75462]

Originally Posted by Pmcmath

So had my def header replaced for the second time and they found my lines to be crossed. The flipped them around and it changed my temp gauge readings. It used to go up to about 210 and then the fan would kick on and run till it cooled.to around 170. Now my gauge stays around 190 and the fan runs constantly and will cut off for about 3 to 10 seconds and turn right back on. Has anyone else had the issue? I traveled for 3 hours and out of that it probably ran 2 hours 50 minutes.

Has any work been done on the chassis A/C recently?

[EA37TS]

No change in fan operation after def head replacement. Where were you traveling to and was there even the slightest change in elevation?

[Pmcmath]

Yes they recharged the ac while at the freightliner dealer. Also it was all flat land as I was traveling down the Ohio and Indiana trek.

[Pmcmath]

Originally Posted by Drv

I would say you need to reach out to FCCC, as what you are describing does not sound like "normal" after DEF Head replacement. The behavior of your fan prior to replacement was and is consistent with how my unit acted before and after DEF Head replacement.
I had to have mine changed out due to total failure this past July.
Im assuming nothing dramatically changed in your overall engine load, speed and ambient temps were similar pre and post DEF Head replacement?

No nothing change except from when it went into the shop and came out.

[75462]

Originally Posted by Pmcmath

Yes they recharged the ac while at the freightliner dealer. Also it was all flat land as I was traveling down the Ohio and Indiana trek.

Sounds like they overcharged the A/C.
What turns the fan on is a refrigerant pressure switch.
When enough heat builds up in the condenser and refrigerant pressure rises the fan comes on to remove the heat. If the system is overcharged it will have very high head pressure and the fan will run all the time.

[SloPoke]

Originally Posted by 75462

Sounds like they overcharged the A/C.
What turns the fan on is a refrigerant pressure switch.
When enough heat builds up in the condenser and refrigerant pressure rises the fan comes on to remove the heat. If the system is overcharged it will have very high head pressure.

** Good explanation!!!! ** Do you have (can you share) a schematic / wiring diagram that shows where that pressure switch is in the liquid line?

[75462]

Originally Posted by SloPoke

** Good explanation!!!! ** Do you have (can you share) a schematic / wiring diagram that shows where that pressure switch is in the liquid line?

I think it’s the switch on the left in the picture.

[75462]

Yes, it is the switch on the left. When you first start the engine with the air conditioner off you can unplug the switch and the fan will come on. Once the switch is Plug back in there is a slight delay before the fan will shut off. This switch opens on a rise in pressure to turn the fan on so if you ever had a broken wire or an failed open switch your fan would then run constantly.

[Chuck R]

So I have an on going parasitic draw on my chassis battery. I think I narrowed it down to the radio fuse , drivers side fuse box by the emergency brake. I pulled the fuse and the chassis battery maintained 12.6 to 12.7 Volts for 24 hours. Jensen radio with cameras. 2016 E450. Any thoughts out there.

Chuck

[SloPoke]

Originally Posted by 75462

Yes, it is the switch on the left. When you first start the engine with the air conditioner off you can unplug the switch and the fan will come on. Once the switch is Plug back in there is a slight delay before the fan will shut off. This switch opens on a rise in pressure to turn the fan on so if you ever had a broken wire or an failed open switch your fan would then run constantly.

I did not pull the switch connector, but did see that the engine fan kicks in at different cycles with the AC on "vs" off.

Ambient air during this test was 101F (today)