I would say yes. Finding a location (highest point in the system) in which the air can be bled off while the engine is hot (releasing pressurized air in the coolant system), then allowing the system to draw water back out of the reservoir as it cools down. This is where a purge tank is really useful (if I'm correctly using the purpose of that tank). I eventually purchased the AirLift product, which has been a godsend in being able to fill the system, and no longer having to burp, refill, rinse and repeat each time I perform maintenance on the coolant system.