Alternate temp guage for Yong Heng compressor

[kentek314]

I bought a temp gauge with a F degree setting that I would like to install on my compressor. Only the sensor is slightly larger than the one that is provided with the compressor. It would require me slightly enlarging the hole that is already provided on the compressor.

How much of a risk would it be to enlarge this hole by less than 1 mm?

Here is the device.

 

[idoc]

Can you use the sensor from the old gauge?

 

[bandg]

If you can return that one, there is a F gauge available that fits without modification. I have one and it was a simple change.

 

[biohazardman]

If you don't want to do either of the above I would expect, in a worst case scenario, the only problem would be drilling to far into the head and breaking through which is not likely to happen. If it did you could fix that by tapping the hole and using a setscrew for a plug so seems safe to drill to me.

 

[hollowpoint]

If you really want a F gauge, I'd strongly suggest swapping out the thermometer for one of the same style in Fahrenheit. Don't bother drilling out the cylinder head to install the temp gauge you already bought. You won't be able to mount it cleanly in the panel because of the overall size difference. There are also way more parts/features on that circuit board than necessary. These compressors shake the everliving crap out of any component attached to the motor and reciprocating assembly, there's always the possibility that the temp gauge you originally ordered might prematurely fail due to all the vibration anyway.



For a drop in replacement, order a gauge from here. Make sure to select the right model (in AliExpress, it will be listed as "color"). You want the 3rd model from the left, which is a Black gauge with 1M cable in Fahrenheit. AliExpress will have it listed as: "Color: Black with 1M Cable". You know you'll have selected the right one when the product picture shows a black gauge with 78.0F on the display. If you can wait over a month for it to ship, choose the cheap shipping option at $0.65. If you want it faster, select EMS - ePacket shipping for $2.63 and you should have it well within 2 weeks, probably a week.

https://www.aliexpress.com/item/32966100423.html?spm=a2g0o.cart.0.0.5b6d3c00kJ6G2U&mp=1



If you have a little experience tinkering, ALL of the Centigrade thermometers that ship with our compressors can be switched from C to F. I've taken apart my thermometer to get to the circuit board, and while I was in there I found there's a pin labeled "F" for Fahrenheit, and if you short that pin to the ground pin, the board will display temps in F instead of C. I didn't permanently do this mod to my thermometer because after some thought, I don't mind it showing Centigrade even though I have pretty much no mental reference of temperature measured in C. For me, if I see my thermometer start to show anything higher than 60, I'm starting my bleed down procedures to cool the system off. I don't really care what the exact temperature of the cylinder head is, all I want to know is when to shut it off.

 

[USAFANG6799]

I bought one of these from Amazon. I recently changed out the Head on my YH compressor and the hole was smaller.

"Digital Refrigerator Thermometer LCD Display Thermostat Oven Thermometer Freezer Electronic Temperature Hygrometer with Probe for Vehicle Fish Tank Aquarium Incubators Brooders Climb Pet(Fahrenheit)"

I drilled it out being careful not to go too deep.

The gauge was a slight bit larger but nothing that a little sanding and silicon grease could not fix.

Works fine.