I recently had a roommate try and replace our old mercury heat pump t-stat with a new programmable wifi digital. When he tested it the fan wouldn't work. A help line said to connect g, c and y to test it. This burned out our board. We replaced the board and still nothing. He went out and got a new motor and run cap. We installed them but still no fan operation. We put the old t-stat back on and manged to get the relay to click but the fan still won't start. We have 24v between c and g. Also there is 120vac going to the fan. The old fan had a high, med and low connection. The new one only has high and low. I wired it in as best I could, minus the med wire. Is there anything else I should try?

When was the last time that you experienced this problem? Did you already consult anyone else like technicians? They might help you especially if the blower motor is involve.