ITC-308 Wifi used to power pump for heat only

So I use the ITC-308 Wifi to monitor the pool temperature. It’s plugged into a digital timer set to power on for 18 minutes and off for 1. I have the temp set to 86 for heating with the Differential set to 3. The heating outlet runs a recirc pump to flow water through a on demand water heater. The system runs fine but something happens after a while. Even with the CD set to 30, I still come back to find the Inkbird in cooling mode and the Setpoint is at 77. I don’t want any cooling to happen at all. Is this item able to accommodate this task or do I need something different?

Maybe the ITC-308-WIFI triggered the special temperature mode.
Please let it cool down to the target temperature and it will enter normal temperature mode. Please check that will it turn on the cooling output again before it reaches 107 degrees? During this period, please be careful not to enter the setting mode by SET button or app, otherwise it will re-trigger the special temperature mode.
Please refer to this post: