"James Sweet" wrote in message
news:zquzd.3971$Y57.676@trnddc08...

| Entirely possible, though that still doesn't change the fact that the
| igniter is apparently not the problem in this particular case.
|
| That is a good point though, the two common types of sodium lights are
| pretty distinctive, but people very regularly misidentify metal halide
| lights as mercury. A probe start MH lamp will usually light up fine on a
| mercury ballast but fail within a couple months. The other way around is
| acceptable for 175W and larger sizes though.

No replies from the OP so at this point speculation is moot???

FWIW, I always try the easy things first. The other way around tends to lead
to much vigorous cursing!

N