Vancouver remained unbeaten with a 2-1 win over the previously unbeaten Dynamo.
Harvey struck after latching onto a header back across goal as the Houston defense looked on, slotting the ball home to put his team up 15 minutes in.
Miller converted a penalty early in the second half after Kofi Sarkodie was caught handling the ball in the box after a poor slide tackle.
Ricardo Clark pulled one back for the Dynamo in the 75th, setting up a slightly frantic finish by heading home a Brad Davis ball in, but it wouldn't be enough.
The win moves Vancouver to the top of the Western Conference and leaves Houston second after its first loss of the season.