I have a Pentair MinMax NT propane gas heater. It's about 10 years old. I've had to replace sensors before and make some repairs where critters chewed on cables and tubes. It had been working okay. I recently tried to turn it on. Temperature shows 79, which is accurate. Heat set to 98 for the spa. When I push the spa button the pressure switch light comes on and then thermostat light comes on but it doesn't get any further. The blower doesn't start. There are no error codes and no warning lights on the inside, including on the back of the circuit board.
I'm not sure where to start looking without an error code. It could be a blower problem, electrical, fuse.
Any advice on where I should start?