Some basic things to check that are cheap / free before you do anything else:
- check to make sure that the spark ignitor bracket is securely mounted, to get a good spark the bracket needs to be grounded thru it's mounting self tapping screw.
- check the connection from the control board to the spark ignitor wire
- see if the insualtion on the spark ignitor wire is not damaged
- check to see if the spark gap is the right width, if spark is marginal the gap may be a bit too wide. Try to make it the width in the manual, gap too narrow and you'll get a spark, but spark might not have enouigh energy to light the propane.
- make sure your DC power connector on the water heater is making a solid connection, corrosion on contacts can reduce the power and is another way you could be getting a marginal spark.
- I always replace the spark ignitor before letting anyone claim the control board is bad. It is a cheap part that costs less than $ 15 and is a DIY replacement if you have basic handyman skills.
Randy - Manhattan, Kansas
2015 Vista 27N
2016 Honda HR-V