pilot light and gas supply?

DomesticEngineer

Last week I noticed while I was near the boiler while it was firing that it sounded like it was pulsing.  A whoosh-quiet-whoosh- quiet where each might last a second or so (not as big a whoosh as when the boiler kicks on).  So Saturday morning we found the house cold  and the pilot light out.  At that point we replaced the thermocouple as I was having problems simply relighting it.  After adjusting the height on the new thermocouple it fired up but is still doing the whoosh-quiet thing.  The pilot had gone out again Saturday night but lit easily and has stayed lit since.



Any ideas why the boiler isn't the normal dull roar while it's firing?  Same thing causing pilot light to go out?



Thanks!

nicholas bonham-carter

pulsing burner

could there be another gas fired device on the same [perhaps undersized] line?--nbc

DomesticEngineer

Two gas appliances

We have only the boiler and a gas water heater for gas appliances.  We've had the water heater since we moved in three years ago.  Seems unlikely there would now be a problem.  Also, it is doing the pulsing thing even if the water heater isn't firing.

Tim McElwain

It sounds like you are not getting a smooth

light off on the call for heat. There are a number of things that can cause this. It is a safety issue for sure so I would suggest you have a professional take a look at it.

Rich_L

How's your weather?

If it's been windy and wet, then a quick temperature drop, I've had gas line regulators outside near the gas meter freeze up and cause this. Moisture gets inside the vent, blocking it or near or on the diaphragm and won't let the pressure regulate like it's supposed to causing a weak flame or everything to go out. A call to the gas company could determine if this is the problem and they don't charge for this in my area.

Dave in QCA

right track

I have seen this exact same sympton, and it was caused by an iced up major regulator station that feeds the low pressure distribution in the neighborhood.