aleifuu
Posts: 18
Joined: Sat Sep 17, 2016 9:50 am

About this (weird) humidity graph

Tue Jan 31, 2017 4:54 am

Hi all,


for past months I have been monitoring the humidity levels in several rooms using senseHat+pi3 unit and the unit did wonderful job logging humidity condition all day long

I though I'd post 2 different readings to this general discussion because whatever these readings show ... I just thought it's beyond normal for one particular room

Both units are in the bedrooms where Air-Conditioning unit turns on from 10pm - 6am the next day
Graphic 1 ( upper ) shows what seemed to be normal reading
Graphic 2 ( below ) shows ... spike chart and happen all night long untill morning

Image
Image


I'm not an expert in the field, but I build this mini logger because I'd get itchy/irritation up inside my nose often whenever I'm in the house. Who knows there will someone expert enough to make sense of these reading ....

Cheers

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Jednorozec
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Location: Deposit, NY

Re: About this (weird) humidity graph

Tue Jan 31, 2017 5:59 am

What happens if you swap the Pis between the rooms?
The most important leg of a three legged stool is the one that's missing.
It's called thinking. Why don't you try it sometime?

aleifuu
Posts: 18
Joined: Sat Sep 17, 2016 9:50 am

Re: About this (weird) humidity graph

Tue Jan 31, 2017 8:56 am

@Jednorozec : same result, I know you are suggesting there may inconsistency issue if one pi reading is actually faulty but it's not. If I swap the pi, the pi in the 'abnormal' room will still display these spikes reading. And I did check using hygrometer, that it sometimes could go high and drastically low hence the spike on the graph

MarkDH102
Posts: 340
Joined: Fri Feb 13, 2015 3:18 pm

Re: About this (weird) humidity graph

Tue Jan 31, 2017 9:24 am

Do I also detect a small oscillation of the temperature that is in synch with the humidity oscillation?
Are you sure the AC unit isn't switching on and off in a similar cycle?
What period of time does a complete up/down humidity cycle have? Can you relate that to anything that may be happening externally?

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joan
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Location: UK

Re: About this (weird) humidity graph

Tue Jan 31, 2017 12:31 pm

How many hours does each graph cover?

stijn.ghesquiere
Posts: 27
Joined: Sat May 19, 2012 9:44 pm

Re: About this (weird) humidity graph

Tue Jan 31, 2017 1:40 pm

Looking at you graphs, I would say that the airconditioner in the 'abnormal' goes on/off during the night.
Once it's on, the temperature decreases, and so does the humidity. This is completely in line with what airconditioners do. They lower the temperature and water condensates on the cooler, which is removed through a drain.

Is the 'abnormal' room smaller? Or does it have a larger airconditioner unit? Or do you have one unit with two compressors?
Could be that the inside unit keeps blowing, yet intermittently cools. You probably won't hear that.

aleifuu
Posts: 18
Joined: Sat Sep 17, 2016 9:50 am

Re: About this (weird) humidity graph

Tue Jan 31, 2017 2:20 pm

Hi all, I'm happy this post got some more response than I thought it would

The logger logs all day long, but the AC usually turns on from 10pm - 6am the next day, so about 8hrs running

The 'abnormal' room is bigger than the other room. It's about 6x6m, while other room maybe around 4x3m

The 'abnormal' room is installed with both a central air-conditioning AND 1.5pk split wall-mount. Yes, it has two and I will explain in a minute why it has this kind of arrangement

Other room is installed with a 1.5 pk split wall-mount, same brand with other room ( Daikin brand )

The 'abnormal' room initially installed with central air-conditioning, and during my episodes with my nose I built this mini-logger because of my suspicion that it's gotta do something with the air/temperature/humidity in the room. and I was very surprised that the logger would generate a graph that is spikey in nature ... that's why we installed a secondary unit, a 1.5pk split wall-mount and curious how the graph would look like. Overall, the graph is still spikey but not as "wild"

aleifuu
Posts: 18
Joined: Sat Sep 17, 2016 9:50 am

Re: About this (weird) humidity graph

Tue Jan 31, 2017 2:28 pm

MarkDH102 wrote:Do I also detect a small oscillation of the temperature that is in synch with the humidity oscillation?
Are you sure the AC unit isn't switching on and off in a similar cycle?
What period of time does a complete up/down humidity cycle have? Can you relate that to anything that may be happening externally?

The oscillation, in my opinion, is pretty extreme because the RH (Relative/Humidity) readings can go from 50 range to 70 range in about 15-20 minutes time before it goes back to 50 range again. So that's how long the time frame for each 'spike' usually is

How do you check the AC unit is switching on/off in this time frame ?
This is not the kind of eco-AC that has that automatic on/off feature, I suppose it's everyday standard central AC that you can only set :

1. You want it to cool/dry/fan
2. The temperature
3. Timer for it to switch off after 8 hours for example

The AC people that I invited the other day said that there may be leaks coming from outside air that came into play, and suggest that sealing the leaks may help stabilize the humidity. Well, we just did that but the graph is pretty much the same. There are still spikes ...

For other facts, I live in Indonesia and boy, we are hot and humid down here ... outside temp is usually at 30C and humidity level is about 75%

stijn.ghesquiere
Posts: 27
Joined: Sat May 19, 2012 9:44 pm

Re: About this (weird) humidity graph

Wed Feb 01, 2017 10:38 am

How far from the AC unit do you take readings?

If you happen to have a system so measure electricity use (example open source project https://shop.openenergymonitor.com/), you could monitor it.

My air conditioning system is as simple as yours. No eco mode etc.
It's electricity use looks like this:
ac.png
ac.png (42.23 KiB) Viewed 1416 times
Its goes on-off with a +-15 minute cycle, while it keeps blowing the whole time.
Perhaps your unit does something similar?

I'm tempted to place a humidity logger there, after having seen you graphs...

aleifuu
Posts: 18
Joined: Sat Sep 17, 2016 9:50 am

Re: About this (weird) humidity graph

Fri Feb 03, 2017 10:42 pm

Hi @stijn.ghesquiere, the logger unit is placed near centre of the room from the AC

Yes I've been looking for ways to measure the electricity consumption as well. see if there are similar on/off pattern as well. However, it seems there are other factors come into play that effects the humidity level when the AC is turned on. I just don't know what yet ...

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