- Sat Apr 11, 2015 2:33 pm
#14210
Two days ago my wife let me know that there was no hot water.
Upon checking it seems that the gas pilot light in the water heater was out.
I had just made up a batch of tiny boards with an ESP-201, a 3.3v voltage regulator, and a DHT22.
So - I placed on of these sensors so that the DHT22 was inside the flue of the heater and set it to send the temp/humidity once a minute.
In the meantime we cleaned the heaters air filter and that seemed to let the pilot light work again.
Using mqttSpy I set up a subscription to the DHT22 module and let it run, graphing the temperature results.
It was obvious from the graphs that the heater would start, run for 4-5 minutes, then shut off.
It was also obvious that the flue temp always stayed about 10 degrees above room ambient, sensed with another of my $6 temp sensors, so we assumed that the pilot light was running but the main heater wasn't.
I set up a decision in Node Red to email me if the flue temp every equaled room ambient - so a few times during the night we restarted the pilot light.
The repair people and a Google searched told us that the problem was almost certainly the "thermocouple". The repair people can't come out until Monday, and they told me it would cost $245 to replace this part.
A friend of my son works on this stuff and he assured us that that part can be had for $10! And that he'd come over after work this evening to replace it for us.
I can't wait to call the repair folks Monday morning and cancel their $245 visit!
I wish I had screenshots of the pretty graph of the flue temp going up and down, and the humidity going up and down in sync. But my little notebook I was using mqttSpy on (my first time using it) lost the graphs.
Anyway - the ESP/DHT22->Wifi->mqtt->Node Red solution really showed its value!
As mentioned, this was the first time I used mqttSpy - it's is a really terrific program!
I log all of my mqtt traffic to a MySQL DB, and I'm very much a novice at using MySQL. I was wondering how I could get the data out to analyze it, then discovered that mqttSpy can graph various things - problem solved!
This little adventure went a long way in convincing my wife that me playing with trying to automate our house is indeed a good thing.
Upon checking it seems that the gas pilot light in the water heater was out.
I had just made up a batch of tiny boards with an ESP-201, a 3.3v voltage regulator, and a DHT22.
So - I placed on of these sensors so that the DHT22 was inside the flue of the heater and set it to send the temp/humidity once a minute.
In the meantime we cleaned the heaters air filter and that seemed to let the pilot light work again.
Using mqttSpy I set up a subscription to the DHT22 module and let it run, graphing the temperature results.
It was obvious from the graphs that the heater would start, run for 4-5 minutes, then shut off.
It was also obvious that the flue temp always stayed about 10 degrees above room ambient, sensed with another of my $6 temp sensors, so we assumed that the pilot light was running but the main heater wasn't.
I set up a decision in Node Red to email me if the flue temp every equaled room ambient - so a few times during the night we restarted the pilot light.
The repair people and a Google searched told us that the problem was almost certainly the "thermocouple". The repair people can't come out until Monday, and they told me it would cost $245 to replace this part.
A friend of my son works on this stuff and he assured us that that part can be had for $10! And that he'd come over after work this evening to replace it for us.
I can't wait to call the repair folks Monday morning and cancel their $245 visit!
I wish I had screenshots of the pretty graph of the flue temp going up and down, and the humidity going up and down in sync. But my little notebook I was using mqttSpy on (my first time using it) lost the graphs.
Anyway - the ESP/DHT22->Wifi->mqtt->Node Red solution really showed its value!
As mentioned, this was the first time I used mqttSpy - it's is a really terrific program!
I log all of my mqtt traffic to a MySQL DB, and I'm very much a novice at using MySQL. I was wondering how I could get the data out to analyze it, then discovered that mqttSpy can graph various things - problem solved!
This little adventure went a long way in convincing my wife that me playing with trying to automate our house is indeed a good thing.
