Alternative fan control for a Saxon wood heater

Our home came with a Saxon wood heater but the advertised automatic fan control circuit has never worked and I must get down on the floor to turn the fan on or off manually.

The heater works by heating a cement plate at the top of the firebox and a fan runs air over the top of it which warms the room. If the fan isn't on the heat goes up the flu. If the fan is on when the fire isn't going well it cools the firebox and may extinguish the fire. 

I enquired at the company about getting this fixed or getting a replacement board and they referred me to our local agent who basically said they knew nothing.

The circuit certainly looks quite simple although the markings on the IC have been cleaned off.

My solution was to purchase a temperature controller XH-W3001 that can be used either in heating mode or cooling mode. I've set it to come on when the sensor is over 30C indicating that the fire is hot inside.

The sensor range is only up to 120C so I've put the sensor at the back above the heater. The XH-W3001 was AU$5.98 which seems very reasonable. The mains wires are rather flimsy but should be OK for switching a fan.

The way it works is a little counter-intuitive. It has a "heating mode" and a "cooling mode". I'm using it in cooling mode where the output comes on when the temperature exceeds the left hand value and goes off when the temperature drops below the right hand value.

I've set left to 34C and right to 30C. The sensor is at the back just poked in to the top cavity. It seems to be working well and the cat is very impressed.