Outdoor temp & humidity sensors

dr pepper

Well-Known Member

Most Helpful Member

• Mar 3, 2020

• #1

I have a weather station.
It uses DHT22 & BMP280 sensors as well as others.
The sensors mentioned above have both gone haywire, looks like they dont survive outdoors during English winters.
Any suggestions on sensors that can cope with our miserable weather?

 

S

schmitt trigger

Well-Known Member

Most Helpful Member

• Mar 3, 2020

• #2

Those also don't survive Texas summers, either.

In the past, I've used successfully the Honeywell HIH4000 humidity sensors. You have to shield them from direct light and they are expensive, about US$16, but they are rugged.
Oh! and I forget: its output is a nonlinear analog voltage, with some temperature dependency to boot.

 

dr pepper

Well-Known Member

Most Helpful Member

• Mar 3, 2020

• #3

I might have one similar to that, I'll have a look.

 

P

Pommie

Well-Known Member

Most Helpful Member

• Mar 3, 2020

• #4

I found the DHT22 to be unreliable until I discovered that it needs a pullup on the data line.

Mike.

 

dr pepper

Well-Known Member

Most Helpful Member

• Mar 4, 2020

• #5

Yes I have a 10k pullup.
And the temp reading is still reliable and accurate, its the humidity that keeps reading 1%, I'm fairly sure its the sensor element rather than comms.

 

Nigel Goodwin

Super Moderator

Most Helpful Member

• Mar 4, 2020

• #6

dr pepper said:

Yes I have a 10k pullup.
And the temp reading is still reliable and accurate, its the humidity that keeps reading 1%, I'm fairly sure its the sensor element rather than comms.

Click to expand...

Must admit, I've found the DHT22 humidity readings a bit suspect, the temperature always seems fine though.

 

dr pepper

Well-Known Member

Most Helpful Member

• Mar 4, 2020

• #7

One things for sure 1% humidity on a day like today isnt right.
Neither is 1268 millibars for atmospheric pressure.
I hope the thing hasnt got insects in it, hate the little critters.

 

S

schmitt trigger

Well-Known Member

Most Helpful Member

• Mar 4, 2020

• #8

Same experience here. Temp readings were OK, but the RH readings were clearly and totally out of whack.

 

dr pepper

Well-Known Member

Most Helpful Member

• Mar 4, 2020

• #9

I found this in my stash of machine parts, its a pneumatic silencer for a directional control valve, the white thingy is very porous you can blow through it.
I was thinking it would make a weather resistant housing for a DHT22 or SHT05, might be a little more 'professional'.