hugh5
Oct 29, 2011, 06:12 PM
I have high efficiency gas furnace about 10 years old.It is NUGM075EGB1 made by Intercity products corp.
The problem I have is cycling. In the morning the programmable thermostat call for a temp rise from 18 C to 21C. After about 30 minutes the flame turns off and so does the combustion fan. But the temp at the thermostat is only 19C . The duct temp is only 126 F .The main blower then turns off after 3 minutes even though the duct temp is still at 90F. About 2 minutes later the furnace starts its cycle again. If it was the upper temp limit it should not have turned off the combustion fan at the same time as the burner went off according to the installation book. I am stuck .Can anyone help me.Thanks Hugh
The problem I have is cycling. In the morning the programmable thermostat call for a temp rise from 18 C to 21C. After about 30 minutes the flame turns off and so does the combustion fan. But the temp at the thermostat is only 19C . The duct temp is only 126 F .The main blower then turns off after 3 minutes even though the duct temp is still at 90F. About 2 minutes later the furnace starts its cycle again. If it was the upper temp limit it should not have turned off the combustion fan at the same time as the burner went off according to the installation book. I am stuck .Can anyone help me.Thanks Hugh