CPH is in the thermostat. It digital mimic of a heat anticipator. Set to 3. It will attempt to do 10 minute on, 10 minutes off. On Honeywell thermostats CPH is only accurate(maintained) at the equipments 50% load. Above or below that point it my do more or less cycles.
On the GMH. If you set the stats CPH to 3 or 4, you won't get run times longer then 10 minutes, until its past the homes 60% heat loss mark. So it won't time into second stage, since it can be set to 12 minutes of first stage before it goes to second stage. Weather 3 or 4 CPH works better, is dependent on what the person/customer wants.