About This Project
I´ve made a DIY-Garden-Whirlpool out of an old IBC-Tank with 1000l and i want to control all stuff via web.
I´ve used in an earlier version webiopi for this but now i´ve changed all over here to Cayenne.
The Whirlpool (sadly currently without whirl) is equipped with a small filterpump and a heater. I´ve checked multiple methods of heating the 800l water to temperatures of about 36-40 Grad Celsius. It was to expensive to get this amount of water hot all the time. The electrical heater are only 2kW which could ± heat only 3Grad/h.
After a while of studying the net i was thinking about a Webasto Diesel car heater with 5kW which i can run with Heizöl.
I could get one cheap on ebay.
After a few tests with about 100l water i was ready to get this into my whirlpool.
The water flow is Pool -> filterpump -> heater -> Pool
There are 3 Temperaturesensors:
- Water temperature
- Heater output temperature
- air temperature
Due to electrical safety, i´ve no 220V at the pool, only on the controlerbox which is about 3m away.
The filterpump works with 12V AC from its own power supply and the Webasto stand heater works with 12V DC.
- Raspberry Pi B+
- 12V powersupply with 17A current max
- Car 12V to 5V-USB Stepdown for the Pi
- relaisboard with 2 relais
- Box for installation
- 3 x DS18B20 Temperatursensor in waterproof housing
Triggers & Alerts
I have to ensure that the heater can not be switched on without switching on the pump which pumps the water through the heater. So one trigger says “if Relais Heater on than Relais Pump on” and another one is “if Relais Pump off than Relais Heater off”.
Another point is that the temperature in the pool should not rise above 40Grad Celsius so i have set up a trigger which takes the heater offline when the watertemp is over 38Grad Celsius
I´m switching the filterpump off during nighttimes to minimize the temperature loss.
For security reasons this trigger switches also the heater off if it may be on.
Photos of the Project
The things on the photos are not final builds. Most is "work-in-progress"
So i´ve now a new housing for the controller, power supplys which is realy waterproof