I'LLJUSTFABIT

Ran into an odd scenario this past Saturday.
2000 XJ, 4.0 Auto.

6:00 am Saturday morning, 29 F. Snowing.
While climbing a long hill, paved road, 4 high, the temp started to climb and eventually reached 220 F.
I switched on the heat, full hot, fan on high as a way to bring the temp down. Finally I crested the hill and with less load and maybe just a few MPH more the temp started to come back down to a more normal range 200F.
Once I go a chance to pull over and assess the situation the first thing I noticed was the AC condenser was covered in ice/ snow obviously blocking air flow through the radiator.
My AC doesn't work and I just got this Cherokee about a month ago so I haven't had a chance to find the leak yet ( I assume the typical Evap leak)

So the question is;
Would properly functioning AC actually prevent the condenser from icing over due to snow?
My thought is the normal cycling of the AC would keep the condenser warm enough to melt off the snow. It was snowing pretty hard.
On top of all this we have a "Blizzard" blowing in tonight & tomorrow, I filled a squirt bottle of windshield de-icer to spray on the condenser in the mean time.
I was hoping to fix the AC this Spring but it may be a better idea to do it now.

Thoughts anyone?

Bob

djb383

What cooling system maintenance has been done? 220* in freezing ambient and running the heater sounds like there r cooling system issues. Running a/c in freezing cold weather doesn't sound right.....neither does overheating in freezing cold weather. Again, sounds like cooling system issues.

crabmushrooms5

I would think that the ac on would demand more engine power therefore creating more heat. Have any air pockets in your cooling system? Mechanical fan clutch in good condition? Heard 4lo tends to keep things cooler mostly the transmission. All my research of overheating was for beach driving but relative I think (slow speed and 4x4 engaged)

I'LLJUSTFABIT

I've only owned the Jeep for a month, it does have the original radiator and the coolant tested good with a hydrometer. I can only guess the previous owner changed the water pump and T stat as I can see newish looking RTV sealant around the water pump and T stat housing.

I disagree, AC condenser was completely blocked with snow, no airflow through it was possible.

The AC compressor function normally cycles in all but 2 climate control selections, if you're running defrost it cycles...mine doesn't since the there's a leak and not enough pressure for the AC system to work.
So far since owning it it's never reached anything over 200 F except this time with the snow covered condenser.

I'LLJUSTFABIT

From what I understand the AC will cycle as a normal function in all but 2 climate control positions.
It's possible there's an air pocket, I'll try burping it tomorrow.
I was able to maintain 40mph on the hill where it iced up the condenser, no need for 4lo.

sycoglitch

I have an 01 and even when my condenser is packed I stay below 210 (gauge reading). Heat of the engine melts a lot of it away too. Have you tried blocking some of the grill to prevent the packing of snow.

How's the temp normally

Fred/N0AZZ

I would get the AC sorted out first as it helps a great deal in the winter as far as defogging/deicing. It also sounds like you do have other cooling system issues that need to be found from the radiator to heater core both could be all clogged up or just need to be replaced due to age.

A new radiator from AutoZone they have a good unit for about $100 my son and I both have them on our XJ's and I have another on a Ford Power Stroke zero issues and direct fit.

Another excellent point made is to cover in the front of the cond/radiator to keep the snow from packing into them.

djb383

Disagree all u want.......220* in freezing cold weather ain't right. Think about it, were there other vehicles on the road that also had snow in their grille and were pulled over getting toasty?

Your cooling system sounds like it is borderline at best OR your gauge is lying to u. There's plenty of room on the sides, top and bottom of the condenser for the rad fan to pull thru adequate air flow to/thru the rad in freezing weather driving conditions AND using the heater AND all cooling system components r n top notch condition.

I believe it's been post here that the compressor will not engage in freezing temps so if that's the case, how would the condenser heat up in freezing cold weather?

Keep an eye on things......unless the glove box is full of maintenance receipts, I always presume the previous owner did nothing....after all, it is a 15 year old used vehicle. Any vehicle that's expected to be a reliable daily driver deserves regular TLC maintenance. U know preventative maintenance has been done when u do it yourself. Preventing a future problem in one's driveway on a Saturday afternoon while all the parts stores r open sure beats doing repairs on the side of the road.

drhoward1988

When your ac is in cool then condenser is removing energy (heat) from the refrigerant. The likely hood of it freezing is null. If anything it adds heat into the radiator. When your heat is running (no ac cycle) energy is transfered into the cab through the hot water coil (Heater core) into the system. Sounds like you have cooling system issues unrelated to the HVAC side of things