Thermometer Accuracy!

Getting some interesting readings from my thermometers after having installed my second 6" 440 CFM fan into my grow room. Dimensions of the room are 4x8x6 with two 600w cool tubes and two 440 CFM inline fans with an additional booster fan further down the line. I have a total of three thermometers in the room, and two of them are black and are reading temperatures ranging 91-97 degrees. The third thermometer is white and has a temperature probe that sticks up and reads 79... Obviously, black absorbs light and white reflects it, so I'm having a real hard time determining if the temperature in the room is in a nominal range or not. With a combined 1080 CFM the air is being refreshed 5.5x a minute. There are also two filtered 6" intakes.

I have a hard time believing the temps are into the 90's but I am unsure and aside from buying some oscillating fans have exhausted all my options to cool it as an AC wouldn't work in this location. An oscillating fan would simply do a better job at creating a uniform temperature across the room.

What do you guys think? There is obviously a very considerable differential between the black and white thermometers. Can I trust the white one or would that not be an accurate representation of the temperature?

Room location and insulation is as big of a factor as cfm/btu, are you in the basement? Ground floor? Is the roof above your grow space exterior? I ask because I have a small space like yours and have been through this too many times.

1. Placement of thermometer Is key, if it is in any direct light it will readout higher due to radiant heat. Infrared thermometers will do a better job at not giving inaccurate readings due to radiant heat created by your light supply.

My space is located upstairs and is poorly insulated (plaster and lathe on one wall) and the roof gets blasted by the sun the majority of the day. I have plenty of air power and also a 9000 btu ac and I have a hard time getting better then outdoor temps.

I am in the basement. The room my "room" is in is cool, and typically hovers are about 58-68. With my veg tent (which has open ventilation and 3 ballasts running, I'm sure temps will reach low 70s. I have floor vents venting hot air upstairs passively, and the rest of the hot air in the room disperses throughout the drop ceiling in the adjacent part of the basement.

I feel like it's definitely a light problem with the thermometer. This room is completely sealed aside for the intakes and has excellent negative pressure. The only thing that gives me pause is one of the black thermometers has an "outdoor" probe which is about a 10ft length of wire with the temperature sensor at the end, this is hung towards the very top of the grow and above the lights and reads in the mid 90s.

If this is the case, I don't know how much help an oscillating fan would give me. It might very well hurt my cause, pushing the hot air down below the lights. I'm not sure.

My advice

Get some infrared thermometers, get one at canopy level and a few other locations.

I've found these to be as accurate as anything and cheap as it gets, I think I have 6 of them and would gladly use more.

AODE® (2-Pack, Yellow) Digital Aquarium Thermometers Fish Tank Thermometer 600011 https://www.amazon.com/dp/B0177WL8GS/ref=cm_sw_r_sms_api_ff4mxbZXBYHC3

Also a good ol' analog thermometer never does me wrong if hung in the "shady" area of the room.

As far as your black ones I had the same issue with all the cheap digital hygrometer thermometer combos, just inaccurate and very shifty; I still leave one in there but it is always reading higher then anything else even in the shade.

Oh I also got one of those temp guns from Amazon for 15 bucks I think: nice to double check everything with.

Sike. The outdoor probe is actually reading 84, I was reading the indoor reading. So if the top section of the room is 84, and my white thermometer is reading 83 currently, I think it might be safe to assume the readings in the 90's are skewed and the more accurate temp puts it somewhere below 85. That being said, would an oscillating fan pushing the air from the far side from the exhaust towards the exhaust help drop temps more? My Blue Dream can handle some serious temperature but I am afraid on hot days even being in the basement the temps may spike.