i just picked up a chhc-4 and its up and running and have a hyrdo gen hooked up to it my room is sealed. not sure its a problem but the chhc4 does not seem to shut off quick enough if i set my co2 ppm at 1100 when it kicks on and finally shuts off the ppms rise to about 1850 its like the sensor does not react quick enough i have the co2 burner turned all the way down the only way i get it to around the ppms i want is to dial down to about 800 and let it cycle on by the time it shuts down it hits 1450 i have the sensor real close to the co2 burner but that does not help that much i could put it closer. just wondering if anyone had this issue