OMg !
if any of your spouses were to read threads like this,
.. they might not allow any of "their money" to facillitate a Man-cave. Eh?
Aaaanywaaay..
A HV ignitor or transformer is a device which can work, but work "poorly" for a while before it actually dies..
if it doesn't throw a spark across a 1/2 to 5/8" gap easily, toss it.
a prolonged "downtime event" is more expensive than replacement cost.
Consider thhis..
Before you set-out to "safely test one"..
You should hinge the HV open, and remove the HV "electrode assembly" ..aka.. "J-tube assembly" (for the way it's shaped),
And make sure dirty or an out of adjstment electrode wasn't the problem to begin with,
as electrode problems easily over-stress your HV ignitor.
..Just be REAL careful not to break an insulator, but inspect them closely for cracks, and adjust them "my way" for reliability..
Click here, scroll down to the electrode adjustment diagram, and be meticulous.
your Electrode assembly should be cleaned and adjusted every year for reliability.
(now watch.. someone will chime-in here claiming he has gone several years without having a "proper" PM program. Just ignore his example)
AFTER you do that cleaning and adjustment, you prove the HV works or not, like this..
If you are lucky enough to have one of my "BullDogPro Tool Box"..
use the un-insulated alligator clip to bridge a gap across the HV terminals of about 5/8"
(Don't use your roach clip for this test.. it might flame-up and get you high in the middle of troubleshooting..
and forget what you were doing, or worse.. another chapter in 10,ooo ways to die.)
Otherwise, a 2" paperclip works o k too, just make sure that clip doesn't slip ..
Any larger gap will stress the ignitor, and possibly damage it, or finish it off !
Now the easy part..
Get into a position you can see the spark-gap safely, with fingers clear,
..and have your helper start the machine, turn on the heater switch, and open the trigger-gun.. just for a few seconds !
If no helper.. reach into that above described tool box, and grab the magnet..
wave it up and down against the top half of the flow-switch, and observe the HV works, or doesn't.
You should hear the fuel solenoid open and close at the same time, and/or the solenoid that powers the HV clicks on & off.
IF you have a pressure switch instead, it's a little more difficult..
you have to open the pressure switch, gently nudge the micro-switch out, and push the button without shocking yourself.
..or just open the trigger gun youself, and remember..
the control circuit opens the fuel solenoid as well as turning on the HV..
Fuel is dumping into the burner-chamber making a larger pool to burn out, or running onto the floor..
Maybe kids shouldn't try this at home.
..If you are not completely clear on how your system functions.. see or at least call a "qualified tech".
Not an electrician,
not a small-engine guy,
a qualified diesel-fired heater technician.
One last thing..
if there are 2 yellow wires connected in there..
be aware this indicates a time-delay shut-off circuit ..
These are less reliable than the HV..
frequently, the controller quits before the HV.. consult a tech that understands
Upgrading to use a remote relay with this delay-off control.
For more on this, you're going to have to come to my
Pressure Washer Troubleshooting and BulletProofing class.