I have a Jandy Laars lx gas pool heater. When there is a call for heat the fan goes on hi and clears all gases. Then it's supposed to switch to very low until the burners light and then go on hi again. Intermittently it switches to low, but the fan does not slow down enough. The burner lights than immediatly shuts down. After 3 times it locks out and I get an AGS problem notification. When it switches to low fan speed and the fan really slows down it works fine. Any ideas as to why the fan does not fully slow down sometimes?