Issue with Janitrol furnace --

Goes through normal sequence on call for heat - inducer on, pressure switch closes, HSI glows, then gas valve doesnt open. Interesting that the valve has 15-16V consistently until board calls for main valve to open, then 26V at the valve for a few seconds. The 15-16v is to chassis ground and ground on the valve terminal.

I thought there would be no voltage on the valve until a call from the board, thoughts?