Have just changed from propane to natural gas and my heat pump unit is not working rite it has four burners and only one is lighting.all else seems to be working OK.blower turns on and draft blower turns on to gas valve opens and then one burner lites.even after a bit of time the other burners don't lite.if I let it run to long you smell gas in the house.I have manualy lit the other burners and they lite good but will not relight on there own just that one.just moved from New Jersey to South Carolina.and gas company don't service the unit.im a license plumber but retired living on fixed income.need some help please thanks callpass

Can you please describe what alterations you made to the heat pump so as to convert it from propane to natural gas?

Many times you have to change gas valves when going from one gas to another and some gas valves have different stages that control different burners. You can wire the gas valve to have all stages fire at once or according to the t-stat, which is better. W1 is the first solenoid on gas valve marked sometimes as "W-1 or W-2." Then the other stages are W-2, W-3, etc. Actually, the first stage is the reversing valve either dropping out or pulling in. If the reversing valve is wired to "O" it drops out for heat and pulls in for cooling. If wired to "B" it is the opposite. Look at these diagrams: https://dl.dropbox.com/u/8010163/AC%20Wiring%20Diagrams.zip