Infrared Thermometer

I have a "fermometer" on my better bottle but I have been also using a infrared point and shoot type laser thermometer. It is giving me a reading 2 degrees lower than the stick on fermometer (stick on says 74 laser says 72) will there be a noticable difference in the taste if my temp for secondary was at 74?

Both 72 and 74 are on the high side for fermentation.

What kind of beer are you brewing and what yeast did you use?

muscleshoalsbrewer said:

I have a "fermometer" on my better bottle but I have been also using a infrared point and shoot type laser thermometer. It is giving me a reading 2 degrees lower than the stick on fermometer (stick on says 74 laser says 72) will there be a noticable difference in the taste if my temp for secondary was at 74?

Click to expand...

For secondary with an ale that should be fine.

Just a side note about the infrared thermometers. Harbor Freight has recently had the Cen-Tech Infrared Laser Thermometer for like 27 bucks. i picked it up and absolutely love using it with my brews. Its damn accurate.

The tolerance for most of the commonly available infra-red thermometers that I have seen is only +/- 2% IIRC. I think they are probably somewhat closer than that in actual use, but generally they aren't all that accurate.

Here's a spec sheet from Omega listing some of their models and the accuracies:

http://www.omega.com/temperature/pdf/SEL_GUIDE_IR.pdf

Even the relatively expensive ones aren't all that accurate. I have a moderately priced one and it's handy for quick checks of the fermenters and the output of my chiller, but not of much use for anything else brewing related. Steam and vapor coming off of the mash will interfere with the readings and they only read surface temperature. Reflective surfaces can also interfere with them.

Catt22 said:

The tolerance for most of the commonly available infra-red thermometers that I have seen is only +/- 2% IIRC. I think they are probably somewhat closer than that in actual use, but generally they aren't all that accurate.

Here's a spec sheet from Omega listing some of their models and the accuracies:

http://www.omega.com/temperature/pdf/SEL_GUIDE_IR.pdf

Even the relatively expensive ones aren't all that accurate. I have a moderately priced one and it's handy for quick checks of the fermenters and the output of my chiller, but not of much use for anything else brewing related. Steam and vapor coming off of the mash will interfere with the readings and they only read surface temperature. Reflective surfaces can also interfere with them.

Click to expand...

I love my IR therm. I trust it over the fermometer!

passedpawn said:

I love my IR therm. I trust it over the fermometer!

Click to expand...

They have about the same degree of accuracy and either would certainly be close enough for checking fermenters, but as I mentioned, IMO they have very limited other brewing related uses. It is a neat tool to have around and my cat likes to chase the red laser dot. He's easily amused. Me, not so much.

I havent tried AG yet so I will take your word for it as far as mashing and such goes.

I like using it to get a feel for how close to steeping/boiling temp the wort is. It seems like theres always a hundred different things I need to be doing (brewing and non-brewing related) as soon as I get the pot on the burner, and shooting the wort quickly with the gun seems simple to get a good gauge of temp.

And I almost drained the battery in the two weeks of fermenting, especially since I just changed my swamp cooler setup and I wanted to test it (every hour it seemed for the first couple days!)

Maybe I just really am the techno-geek that my wife always says I am.

Captain_Bigelow said:

What kind of beer are you brewing and what yeast did you use?

Click to expand...

brewing a stone DB and pitched a WLP051 ... I was thinking that the gradual warmingto 72 degrees from my 67-68 degree, 18 day fermentation,that I cuold coax the yeast into cleaning up after themsleves a little.

Also, this has been in secondary for a little over a month. brewed it 7/3/10.
will I need to pitch more yeast at botteling? or will there be enough live cells left to do the job?

If you guys are looking for a cheap infrared thermometer that works good Hobby King has one for only $10. Turnigy Infrared Thermometer.

The comments above are correct, it doesn't work good for boiling liquids that have steam coming out as the steam interferes with the readings. But it works good for lots of other things like mixing gelatin for fining or checking fermentation temperatures.

This one is just as accurate as any of them and it is really small. I fly model airplanes and helicopters so that's how I know about it. I use it to check battery temperatures.

We use them at work for checking temps of chemical baths, some up near 190* F. But we have exhaust hoods pulling steam away. They can be nice to have around. The other day I had an oven that wasn't maintaining temp very well. Turning the oven heat on and then shooting each element was all I needed to do to see which element(s) were bad (I know there are other ways but this was the easiest since the 'gun' was about 5 steps away).

Some handy uses for the Infrared thermometers:

1. Checking temp of fermenter before pitching
2. Checking the temp of starter wort in the flask before adding the yeast
3. Checking the temp of wort exiting my CFC
4. Checking the temp of my kitchen oven (I do this by putting a cast iron skillet in the oven then shooting the surface of the skillet). I discovered that my oven was off by 35 F too high.
5. Checking the level of cold beer in a corny keg. This is handy when racking from one keg to another or filling a keg from a carboy with more than 5 gallons in it. Helps avoid overfilling the keg.
6. Checking the temp of cooking oil when deep frying stuff. This works better than I expected and I confirmed my readings with a probe type thermometer.
7. Checking the temp of wort in the kettle when chilling. I shoot the side of the kettle and i can get a reasonable estimate of where it's at.
8. Checking the temp of serving kegs in the freezer, although I prefer to measure the temp in the glass out of the tap.
9. Checking the body temp of my dog when he has not moved all day and appears to be dead. This can be done from across the room. No need to get up from the couch. Might work similarly to see if grandma is still with us in the morning without waking her up.
10. You can use the laser dot as a cat toy and check his temp at the same time.
11. Fun to point the laser at your local gang members and watch them get real nervous thinking that they are being sighted in with a laser scope. You must take care to conceal your position when doing this and don't do it for too long. Trust me on this.

Catt22 said:

9. Checking the body temp of my dog when he has not moved all day and appears to be dead. This can be done from across the room. No need to get up from the couch. Might work similarly to see if grandma is still with us in the morning without waking her up.

Click to expand...

Haaaaaaaah!

Displaced MassHole said:

Both 72 and 74 are on the high side for fermentation.

Click to expand...

depends on what you are making. i did my hefe at 75 b/c i like the esters the yeast give me at that temp. to each their own