Just purchased a refractometer to test my winterizing antifreeze protection. I calibrated the instrument using distilled water as per the directions but when I test my West Marine -60 antifreeze out of the jug I get +9 on the scale. The instrument is for battery solution, PG, and EG. The instructions say to calibrate to zero scale. Which zero?? There is no zero on the battery scale and zero for EG and PG are not the same. When I set the calibration screw to put blue over white at 0% at the bottom of the PG and EG scales I get what appears to be a incorrect reading. There are no phone numbers for support and the name on the instrument is Advances Optics but the web site does not mention refractometers. How do I calibrate this instrument?
Refractometer calibation
- Thread starter Jerry21707
- Start date
So today I took a sample from the hot and cold water lines afterI pumped the WM -60 PG anti freeze thru the potable water lines in my boat. The instrument showed +9 with a sample taken from the transom shower, bath room, and galley faucets. I checked the fluid directly from the jug and also got +9. Does that mean I am protected at -60? Why does the instrument not measure -60 which is on the scale. I am new to this devise. Thanks for the help.
Using a refractometer rather than a hydrometer can over-complicate the situation unless you fully understand how they work and how to interpret the results. One issue is that most refractometer's measures are in a Brix or RI scale, not temperature. Color, temperature variations and other physical characteristics can alter properly interpreting your results. Also, as PG has less effect on sp gravity than other glycols, the results can be misleading. Without getting into the chemistry, you might be better served buying a cheap hydrometer.
Jerry21707- I don't think you are doing anything wrong. I went to the WM website and found this info on the Pure Oceans -60 antifreeze:
You are measuring +9 which is right in the range that they claim it will read. The rating of -60 is for Burst protection, not Freeze Point protection.
Regarding your refractometer, I have one that I have been using for several years. I find it to be fast and easy to use. The calibration is exactly as you described- using distilled water adjust the blue line boundary to the zero on the antifreeze scales. This will also calibrate for the battery electrolyte scale. Both the EG and PG zero lines should be the same- if yours are not then I have no explanation for that difference. I use this instrument for both antifreeze and my batteries with good results.
I don't use antifreeze in my water lines, I blow them out instead. That method is just as easy once you have your connection fittings set up, and there is no antifreeze to buy and nothing to flush out in the spring. In my auxiliary, genset, and A/C systems I use regular EG 50/50. The regualr EP has all of the corrosion inhibitors for the metal engine passages and the metal exchanger tubes in the A/C. I pump through a fixed amount that I have determined will provide me with FREEZE protection to -25 to -30.
The only place I use regular RV (-30) antifreeze is in my head system. Most of that is pumped out through the maserator. I only use it to displace any residual water in the hoses.
You are measuring +9 which is right in the range that they claim it will read. The rating of -60 is for Burst protection, not Freeze Point protection.
Regarding your refractometer, I have one that I have been using for several years. I find it to be fast and easy to use. The calibration is exactly as you described- using distilled water adjust the blue line boundary to the zero on the antifreeze scales. This will also calibrate for the battery electrolyte scale. Both the EG and PG zero lines should be the same- if yours are not then I have no explanation for that difference. I use this instrument for both antifreeze and my batteries with good results.
I don't use antifreeze in my water lines, I blow them out instead. That method is just as easy once you have your connection fittings set up, and there is no antifreeze to buy and nothing to flush out in the spring. In my auxiliary, genset, and A/C systems I use regular EG 50/50. The regualr EP has all of the corrosion inhibitors for the metal engine passages and the metal exchanger tubes in the A/C. I pump through a fixed amount that I have determined will provide me with FREEZE protection to -25 to -30.
The only place I use regular RV (-30) antifreeze is in my head system. Most of that is pumped out through the maserator. I only use it to displace any residual water in the hoses.
I find the refractometor to be fast and easy. Calibration is not as important as making sure that the reading of the anti freeze coming out of your system matches that of fresh stuff in the jug.
If you want to be official make sure you only turn the focus knob clockwise. If it goes past the clearest point, turn it fully counter clockwise and start over turning only clockwise while looking in the reticle.
Just did my engine and got 9 also.
If you want to be official make sure you only turn the focus knob clockwise. If it goes past the clearest point, turn it fully counter clockwise and start over turning only clockwise while looking in the reticle.
Just did my engine and got 9 also.
Also what I meant by the zeros not being the same for PG and EG are the ton emperature scales, The 0% are the same opposite position at the bottom which is where I did the calibration. Thanks again
Jerry
Are you at Carlyle lake just east of St.Louis?
Have fond memories of the place as a kid. The dam was new and the lake flooding for the first time.
How did things turn out there?
Gary
Are you at Carlyle lake just east of St.Louis?
Have fond memories of the place as a kid. The dam was new and the lake flooding for the first time.
How did things turn out there?
Gary
Bottom line:
#1 Use a quality PG antifreeze NOT an alcohol based or alcohol blended product. If it costs less than about $3.49 - $4.00 a gallon it is most likely not a true PG product. West Marine Pure Oceans -50F is a good PG but their Sea Fit -50F is not a true PG it is an alcohol/PG blend.. Be very careful because even Camco, Uni-Guard and many others are now blending PG & ethyl alcohol or selling ethyl alcohol only based "RV antifreeze". Just say no to crappy RV antifreeze!
#2 Test a sample from a fresh virgin bottle & note the reading (-50PG's can vary a bit but none should ever be diluted)
#3 Test each faucet hot and cold, spigots, raw water wash down etc. & generator or engine exhaust and be 100% sure it matches the bottle reading.
#4 If readings do not match bottle exactly suck in more PG
#5 Done
The -50, -60 etc. is marketing "burst point" the refractometer is telling you "freeze point" not the burst point. I don't know of any tool that can measure burst point so DO NOT DILUTE!
Fresh Water System Winterizing (LINK)
#1 Use a quality PG antifreeze NOT an alcohol based or alcohol blended product. If it costs less than about $3.49 - $4.00 a gallon it is most likely not a true PG product. West Marine Pure Oceans -50F is a good PG but their Sea Fit -50F is not a true PG it is an alcohol/PG blend.. Be very careful because even Camco, Uni-Guard and many others are now blending PG & ethyl alcohol or selling ethyl alcohol only based "RV antifreeze". Just say no to crappy RV antifreeze!
#2 Test a sample from a fresh virgin bottle & note the reading (-50PG's can vary a bit but none should ever be diluted)
#3 Test each faucet hot and cold, spigots, raw water wash down etc. & generator or engine exhaust and be 100% sure it matches the bottle reading.
#4 If readings do not match bottle exactly suck in more PG
#5 Done
The -50, -60 etc. is marketing "burst point" the refractometer is telling you "freeze point" not the burst point. I don't know of any tool that can measure burst point so DO NOT DILUTE!
Fresh Water System Winterizing (LINK)
