Heater pilot won't light

[Rack55]

Raypak 156 propane heater, just 3 weeks old. I ran out of propane at the main tanks, and the unit went into ignition lockout.

Had the tanks refilled, but the heater won't fire up. It will attempt to light the pilot, then go back into ignition lockout - no pilot sensed.

I purged the main main gas line using the sediment trap, with no change to the pilot error.

Clearly this is related to me running the propane dry, but I cannot figure out what the issue is. I am not sure if it is actually sparking - the display shows "spark" and makes noises as if it is attempting to spark, but it is more of a vibration/buzz than what I would expect a "spark" to sound like.

Any help or or advice would be greatly appreciated! Thanks!

 

[ps0303]

How many times after you purged the gas line did you try it? Sometimes is might take three tries or so to get it to light. When you get the ILO message, power it off, and then back on and try again.

 

[Rack55]

How many times after you purged the gas line did you try it? Sometimes is might take three tries or so to get it to light. When you get the ILO message, power it off, and then back on and try again.

Thanks for the reply! I have tried about 5-6 times since I purged the line. I can definitely smell propane when it is attempting to light, so I'm left to assume it's an issue with the spark.

I can't see any spark, although the actual pilot isn't obstructed from view as far as I can tell. I can hear the "clunk" of the valve opening, and rhythmic buzzing of the "spark", but is this an indication that it is actually sparking?

I dont understand how this would be a mechanical issue as issue as it was clearly caused by running the propane dry.

Thanks again for the help.

 

[Pool Clown]

The hole in the jet for the pilot, especially on propane units is so small, it takes forever to get all the air out of the line. and while propane is flammable, it takes the right air fuel mix for it to ignite. And even though you can smell propane, you may not have all the air out of the line and the mix coming through the jet is still too lean for it to ignite.

Be patient, keep purging and resetting when it locks out (What Paul said, above).

 

[Rack55]

The hole in the jet for the pilot, especially on propane units is so small, it takes forever to get all the air out of the line. and while propane is flammable, it takes the right air fuel mix for it to ignite. And even though you can smell propane, you may not have all the air out of the line and the mix coming through the jet is still too lean for it to ignite.

Be patient, keep purging and resetting when it locks out (What Paul said, above).

Thanks for taking the time to reply. I will purge again and run it through as many cycles as I can tomorrow. Will purging be effective, considering it seems the air lock would be in the unit and i am purging ahead of the air lock? Also is the sediment trap a good spot for the purge? Is there any way to actually purge the line at or after the ignition switch anyway?

Thanks again for your input!

 

[Pool Clown]

You are on the right track...

You want to get as close to the "end of the line" as you can to open and purge the gas line. With natural gas, there is typically a union next to the gas valve, and that seems to work well. But with Propane, as i stated earlier, just takes longer to get all the air out.

 

[Rack55]

Update - Thanks to Pool Clown and Paul for the advice. They were right about a likely air lock causing the issue and the need to purge and re-attempt many times. Eventually the right amount of propane came through the pilot tube and we're back up and running.

Thanks again, you guys saved me an expensive service call for sure!