I have a Bryant gas furnace which recently had the termostat and transformer replaced. IT worked flawlessly for the last few weeks. Now my furnace is making a repeated clicking sound and the blower is not turing on. In the rare instance the blower does turn on, it only stays on for a minute then shuts off. When I looked at the furnace, you can see a spark in the flame which is making the repeated clicking sound. What could be causing this and what can I do to fix it?? Also is there anyway to manually turn the blower on??