as for mine it will run for four minutes and rest for twelve minutes with the blower (hot air) running for two minutes after it shuts down. this will only take place when i use it on the thermostat terminals on the control box and the thermostat is satisfied at the temp. setting that i use. this on and off action is built in in the control box and is for maintaing a fire when there is no call for heat. it is field adjustable to satisfy different operating conditionsconditions . this is the setting it was set at from the factory and that works well for me.
if i understand your question right it sounds to me it is working properly. most likely with no signal from the digital thermostat is like that it is satisfied and will continue to start and stop as designed.
what did it do with the thermostat that was supplied with the unit?
you can also make up a jumper and remove the thermostat wires. it will run continously and the heat will be controlled by the stroke adjustment on the rear of the stove. i run mine in this manner when i first start it up for the first time firing so i never have to try and dial in the thermostat. after i have a good fire established then i remove the jumper and hook up the thermostat wires and let it run in auto.
i have had mine for nine years and the only problems i have had were self induced due to lazyness