Making best use of hygrometers

ChasingtheWelshdream

I have just bought a couple of smart hygrometers, hooked them up to my phone and can see we have high humidity - 75% in one room (expected - little insulation, condensation, all to sort etc). 

I just wondered how to make best use of these now, without getting obsessed by the data.

I would like to monitor a couple of rooms to see the effect of increasing heat/ventilation and whether some areas are actually ‘damp’ or just need some tweaks.

What do others do? Check them religiously? Plot against wether conditions? Randomly glance at them then forget about them?

tacpot12

I would just check them every day while I was getting a handle on whether some additional heating, e.g. turning up a TRV slightly, was making a difference or not, and then I would just glance at them occasionally to make sure that the problem has not returned. 

We've got our heating turned down a bit at the moment, and the RH in the lounge is 83% today, which is probably too high. 

FreeBear

ChasingtheWelshdream said: What do others do? Check them religiously? Plot against wether conditions? Randomly glance at them then forget about them?

I record temperature and humidity in all the rooms as well as outside. The data is then plotted on graphs on an hourly, daily, weekly, or even yearly basis. At the moment, humidity ranges from 58% up to 74% (currently 82% outside due to rain). Main reason for recording the data is to get some idea of what improvements (e.g. new windows, internal wall insulation) have the biggest impact.

ChasingtheWelshdream

Thank you

FreeBear, do you plot your graphs manually or do you have an app or software?

I would like to see how outside conditions affect the rooms. We have one area with periodic damp patches that could be condensation or water ingress (both are not obvious). I was hoping that if they correlate with either prolonged rain or prolonged cold snaps, it might help us narrow down our options.  It might be we just need to increase the heating (rooms are generally 16-17 degrees), or there may be a leak we haven’t traced.

Also - being in Wales - it is often damp outside. I would like to see if my habit of opening windows helps or hinders.


Am I on the right lines?

ChasingtheWelshdream

Humidity has dropped from 75% to 70% with the window open, whilst the temperature has dropped to 14.8 degrees. (This room has mould on a paper thin wall). Will it get drier when the heating comes on? This could get addictive 😆

stuart45

You could get a surface thermometer as well. This will help tell you which areas are likely to have condensation forming on them.

FreeBear

ChasingtheWelshdream said: FreeBear, do you plot your graphs manually or do you have an app or software?

I use Home Assistant to read all the sensors and run a bit of home automation. The data is stored in a large (and growing) database, influx. From there, the data is plotted via Grafana. At the heart of the system is a dinky little computer, a NanoPi from FriendlyElec feeding the data to a fanless Shuttle PC ('cos it has a decent hard drive). All the graphs are generated by Grafana and displayed on a computer via a normal web browser (Firefox or Chrome).

Sounds complicated, but it is a system that has evolved organically as I've added bits & bobs and wanted more out of it. Got another (industrial fanless) computer to replace the NanoPi & Shuttle once I've offloaded boiler control to an ESP32 with onboard relays - That said, may have to replace the boiler early next year, so can skip the relays and use an OpenTherm interface with the prospect of loads more data to record.

theoretica

Humidity varies a lot more and faster than temperature.  I would suggest having one sensor in a room you aren't making changes to as a control, so you can see how much variation there is which is not down to changes you are making. 

FreeBear

ChasingtheWelshdream said:

Humidity has dropped from 75% to 70% with the window open, whilst the temperature has dropped to 14.8 degrees. (This room has mould on a paper thin wall). Will it get drier when the heating comes on? This could get addictive 😆

Relative humidity is a function of temperature. As the air heats up, it has capacity to hold more water. So for the same amount of water in the air, the humidity (RH%) will drop as the temperature rises.

ChasingtheWelshdream

Are you an IT wizard FreeBear?! I don’t pretend to understand half of that, but I have found my app at least plots a graph agains time of temperature/humidity so I can see ‘ah that is when I flung the windows open’ etc

FreeBear

ChasingtheWelshdream said: Are you an IT wizard FreeBear?! I don’t pretend to understand half of that,

I just dabble from time to time with Linux, Python, and a few other programming languages - Comes in handy on the old CV when I can say "am fluent in several languages"