Measuring Wet Bulb/Dry Bulb & RH

[lihvac54]

what do you guys personally prefer to measure wet bulb/dry bulb and relative humidity... as far as digitially.... i know fieldpiece once again has a head that will measure all 3 but once again im slightly skeptical of the accessory heads...

i know ive writen quite a few threads on tools and measuring devices but im more or less starting to collect some higher quality tools since i got a little extra money around and i like to hear the reviews first

[jpsmith1cm]

Fluke 971.

As far as instruments go, I don't believe that you can beat Fluke for the price.

[ptemko]

Testo 605-H2 Humidity Wet Bulb Stick

I have had a number of different types over the years. UEI, Amprobe, Bacharach. I like the Testo stick because I can stick it right in the return air duct work and get a good solid reading.

[ascj]

I use the Fluke 971 also. The two things I like the most over others I have had are the response time and the accuratcy.

[Texas-Tech]

Testo 605 H2

[badboyheel]

605 h2 a little 1/2 inch hole in duct and your go to go.

[beachtech]

testo 605 here as well

also have an old supco that i use in room to room walk arounds pretty acurate and not terribly slow. great bargain as well

[fcs]

I have the Amoprob.

Next time I'm getting the testo H2

[ryand]

I have all three mentioned above 971, amprobe, and testo H2. The amprobe is made with pretty brittle plastic, the fluke 971 was left on the top of my van and fell off while driving and than ran over and it still works like new, the only thing that happened was the top got bent up and the little plastic piece that closes it when not in use broke off. Very tough tool!! The testo I use the most because you can just insert it into your return and it stays there.

The trick to all of these is to bring it into the house right when you get there because they all need quite a bit of time to acclimate the transition from your hot ass truck to the house

So my vote goes to the H2 for the versatility

[Toolboy]

I have used the "Mannix sam990dw" for years. Very compact, 3/8" round tip 3/4" long fits into most places.Has served me well.

[Kevin O'Neill]

Testo 605 H2. If you check several together, they all read very close to the same thing. With other instruments, they will read all over the place. Accuracy is everything.

[hvacrmedic]

If you're getting a cheap one, then it doesn't really matter which one you get. None will have better than 2.5% accuracy. That isn't good enough to do psychrometrics. It's ok for setting superheat, and ok for measuring crawlspace RH, etc. Most use exactly the same sensor. Do some homework on it first. Some have more features than others. In the least you want it to calculate everything for you, e.g., RH, td (dewpoint temp), wb, and drybulb temp. A dual display is a plus. Mine will read drybulb and any of the other three simulataneously. I use the Testo 610. I'd rather have the 605 at times, but the 610 was free, so I'm not knocking it. The large display and backlight are advantages over the 605. The 1/2" probe of the 605 is an advange over the 610. The Fluke is a monster in comparison to the 610, and doesn't do anything that the 610 doesn't do, AFAIK, other than storing readings (what for? You got a pen right?). BTW, the 610 is great. I'd recommend it to anyone looking for it's particular features.

[geno54]

Dwyer 485-2. need 1/2" hole. Has probe about 12 in long with coiled cord. Great for doing coil splits. Have had it for several years. humid accuracy +- 2%. Takes a few minutes to settle out but thats ok. Wb, Db, Dp, Rh. Combine this with a wetbulb/enthalpy chart and you can do calculations quickly.


http://www.dwyer-inst.com/Products/P...PageName=Specs