Laser Thermometer

yes they are expensive, but It seems that the non-contact aspect would be VERY helpful.

anyone have any experience with them?

I would gladly pay $90 if it works.

will the foam on top prevent an accurate reading?

I wouldn't trust it personally. I have no experience with them, but there's something about reding temps without touching the material that strikes me as inaccurate. Yes, it'd be convenient, but I think that you might be right about the foam. And who knows how far into the wort it's actually taking a temp reading from.

I have a small one that I use when breaking in my R/C airplane engines. It works really well for that. I've yet to use it when brewing, but I'm going to give it a try on my next batch. If it works, I'll let everyone know. Here's a link to the one that I use.

http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXEMG5&P=ML

The technology of reading temps remotely is solid science with good engineering behind it. There is no reason to distrust the results. Univeristy of Wisconsin-Madison Engineering has lots of IR temp readers that they use in the thermodynamics labs all the time.

However, there is one significant limitation: it reads SURFACE temp and only the surface. Surface temps are not aways the best indicator.

Here's an interesting link that suggests you can use an IR thermometer for liquid measurements. Some of these thermometers are extremely accurate - they are used in the aviation industry for a variety of applications. It might be interesting to use one in brewing, but I think I'm probably going to stick with a probe type.

I'm not 100% on this, but I don't think laser thermometers will work on liquids. The article above lists mostly opaque liquids (soup sauces and gravies). Bearing this in mind, there are some applications in the brewing process that IR thermometers are suited for (mash temp and maybe wort temp), but if the solution is clear or mostly clear, you will measure the temp of the vessel.

We messed around with this isuue at work and usually ended up measuring the temperature of the vessel or background material. Another negative for IR is the cost. I have a thermistor thermometer with an immersion probe about 12" long (snickering) that works great. It's very accurate in the brewers range and doesn't lose accuracy as much as other methods i've tried.

Matt

I'm not an engineer or anything, but I have a laser temp gun. I thought it would be awesome, but to tellthe truth, I don't use it much anymore. I just use my floating thermometer, because with the temp gun I get 5 different temps with 5 different shots into the same liquid. If the liquid is clear, I think it reads the temp on the bottom of the kettle. If you shoot your carboy, you get the very surface temp caused by your own breath on the surface, or the a/c vent blowing on it. In other words, I think it measures temperature great, but I can't ever be sure it's measuring what I want it to measure. I wish it was sweet. But for me, it's not. Dang.

monk

The only place I could see it being helpful is in the mash tun but it won't work there since the surface temp is different then tha actual mash temp.

You could use it to measure your strike water and sparge water and Im sure it would work fine but a bimetal thermometer is easier....

I thought about getting one for monitoring the temp. of the kettle during the cooling, but I have way too many gadgets that I don't use.

You would get a good temperature reading for the top of the foam & foam is a good insulator. Anyone who has burned their lip on a hot chocolate with whipped cream can confirm.

I think that what is often referred to as a laser thermometer is actually a laser-sighted infrared thermometer, or an IR thermometer with a laser guide beam or pointer.

I ordered a Kamado #7 barbecue smoker/grill back in June. It is built to order, and it hasn't shipped to me yet. I'm expecting it to ship in about three weeks. It can reach temperatures of up to 1000 degrees F for searing meat rapidly. I mainly plan to use it for low and slow smoking at 200 to 225 degrees. But since there is no other practical way to take grill surface temp readings at 1000 F without roasting yourself in the process, I plan to get a Raytek or similar infrared thermometer that has a range up to 1000 to 1200 degrees. IR temp guns in that range typically cost 90 to 150 dollars, so they aren't cheap, but they are still reasonable if you have a need for one.

I don't think there is really a great need for such a device when you are dealing with temps from 60 to 212 degrees. The range of most of these devices covers that, but it's overkill. Plus, a $35 temp guage installed in each of your kettles is both accurate enough, and more convenient than having to point an IR temperature gun at your wort everytime you want to know how hot it is.

Even so, I'll try it out when I get one, although I don't expect that to be real soon.

I have a laser temp that I use while steeping/sparging that works wonderful and it costs me $15 on ebay.

What brand? Did you check it against another source to determine if it was accurate? Thati is, something like a good quality immersion thermometer?