Hot Surface Igniters - Anyone familiar with them?

[Geof]

I work for a manufacturer of direct & indirect gas-fired HVAC equipment. One of our competitors has started using "premium nitride hot surface igniters" instead of direct spark or pilot ignition systems.

I'm researching them - reading through the literature, and may buy a few to test.

Can anyone give opinions on reliability, ease of use, pitfalls, etc.?

Thanks for your help.

 

[DRWeig]

Geof,

As an end-user I can report no problems with a couple pieces of equipment, about two years experience.

As a subject of a couple group discussions in my engineering circle, the reputation is good. Trade-off with spark style is 1) no high-voltage stuff that tends to deteriorate with time and 2) since it stays hot for longer periods, it should be kinda self-cleaning.

I, too, would be interested in hearing from a wider segment of the trade...

Best to ya,

Old Dave

 

[standardgreg]

As a service eng/field tech I haven't ever seen hot surface ignition used on a direct fired make-up air unit (if that's what is being addressed). Old HSI's were silicon carbide, very brittle after many cycles, and prone to failure. I wouldn't think an HSI would be as reliable in a humid airstream.

 

[Rodale]

Our experience with silicon nitride is good. Failure out of the box is very rare and the parts are tough enough to survive in a service truck.

Stay away from silicon carbide. They are very delicate.

 

[OscarMeier]

I second the comment on silicon carbide. I have had a silicon carbide H.S. ignitor in my furnace for the last 13 years. I have had to replace it three times and they are very deilcate.

 

[lilliput1]

I have a newer RUUD heater with spark type igniter. My mother has a hot surface silicon nitride unit on an older RUUD. Her igniter failed. It cracked. It is so delicate that I broke it when I touched it. I was told you should not touch it because body oil will impair its performance. I think the spark type is better, less troublesome.