How is a tidal range affected when the moon earth and sun are in line?

Spring tides occur in principle when the three objects are lined up so that the gravitational forces of the Sun and Moon are combined. In practice in many places the spring tides occur 1-2 days later.

Tides are a proximity effect, which means that the Moon's effect on the tides is the major effect because it's closer, while the Sun's overall gravitational force on the Earth is much stronger.

Tides happen because the Moon's gravity is much stronger on one side of the Earth than the other, because it's close, while the difference is not so much with the Sun's gravity because it's a lot further away.