When my Octopus Agile energy price is below x pence per kWh for at least y thirty-minute periods then run my Honeywell hot water. Set your own price threshold and the times between which you want this to run - e.g. to heat the water overnight (say between 1.00am and 6.00am) and use this Applet again for a daytime run (say between 1.00pm and 5.00pm). Check your bill for typical prices such as 9 pence overnight and 15 pence in the afternoon as setting too low values will result in no hot water.
Discover more time saving integrations for Honeywell evohome and Agile Octopus