An Accurate A/C thermometer

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Oct 11, 2020 | 08:49 PM

PJWhelan

Thread Starter

Laughing Gas

Joined: Jan 2019

Posts: 868

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From: Florida

An Accurate A/C thermometer

Does anyone know what type of AC thermometer to use to determine the temp from the cabin vents? A friend of mine had a digital reader and it was blowing 61 degree (at night, in Max AC mode). I want to buy one and have it on hand. However driving with my wife she stated "it's not as cold as her 2016 KIA". I am going to eventually go piece by piece in replacing the condenser, dryer and maybe the evaporator. They are all original parts as I don't remember giving them the treatment as I used to live in NY and didn't need AC at all. I usually would drive windows down. I drive a 2002 F 250 4WD CC XLT
Thanks,
PJ

Oct 12, 2020 | 01:14 PM

EDC8008

Fleet Mechanic

Joined: Dec 2015

Posts: 1,521

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From: Washington Coast

Digital meat thermometer has worked for me. Started out with the old dial type.

Before you do anything else you need to take it down and have the pressure checked and they need to verify suction and discharge off of the compressor.

Oct 12, 2020 | 01:23 PM

ford390gashog

Fleet Owner

Joined: Jan 2004

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From: Brentwood,CA

Well I wouldn't use the Kia for comparison. Check the underhood label Kia went to R1234YF as did most manufacturers. It does provide substantially better functionality and does have lower evap temperature.

Oct 12, 2020 | 03:51 PM

Tim C

Senior User

Joined: Apr 2004

Posts: 235

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From: Fayetteville, NC

My old 03 f250 used to blow out 60 degree air, which was cool but not enough in NC mid day unless you were going to be driving longer than 30 minutes. I added a heater control valve as mine didn't have one and it dropped to 55*. if you don't have one, use a Ford valve the aftermarket ones are junk, the grey vacuum hose hooked to the heater box under the hood goes to it. It's hooked to a dummy nipple on the box. I then put in a variable orifice tube, it was $40 vs the usual $3. They make two different ones, depending on local summer ambient temps. That dropped mine down to 40 to 45* air from the vents. HUGE difference. The variable o tube has a spring loaded check ball in it, at low rpm, low refrigerant flow, the spring keeps the ball seated so the freon has to pass through a smaller orifice. Higher rpm and flow the ball unseats and it's a stock orifice size, kind of similar to an expansion valve. If it fails it'll be like stock and the ball is trapped inside the screen like a fail-safe.

My new 16 f250 has an expansion valve instead of the o tube and it cools 40 to 45 stock.

I use a parts store $10 ac thermometer for testing, even at work (I'm a mechanic).

Oct 12, 2020 | 04:20 PM

projectSHO89

Hotshot

Joined: Jan 2004

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From: St Louis

Quote:

However driving with my wife she stated "it's not as cold as her 2016 KIA".

WARNING! If you try to prove your wife wrong, I see great trouble in your future....

Oct 13, 2020 | 09:48 AM

alloro

Fleet Owner

Joined: Apr 2008

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From: 0,0,1

Quote:

Originally Posted by PJWhelan

Does anyone know what type of AC thermometer to use to determine the temp from the cabin vents?

I bought a few of these and keep one in the center vent of each vehicle I own. Using it also helps to keep track of how your heating system is working, not just the AC.