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Phil, Mechanical Engineer.
Category: Plumbing
Satisfied Customers: 8503
Experience:  Retired mech. contractor, shop owner, 51 yrs experience.
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I am finding it increasingly difficult to ignite the pilot

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I am finding it increasingly difficult to ignite the pilot light for my Aquastar tankless hot water heater. I eventually get it lit, but I seem to have to depress the starter button for an extended length of time and repeatedly have to depress the ignite button.

What is the most effective way to ignite the pilot light?

I use the cabin where the system is installed about a week at a time. The rest of the time the Aquastar is turned off.
Welcome welcome to just answer!.

The first step is inspect the spark as you press the igniter... notice that is sparking easily each time, or just sparking occasionally.

If the spark is ok, the next most common problem is spiders making nests inside the pilot/ main burner orifices... use compressed air to blow the dust and any spider webs from the orifice areas... that takes a bit of mechanical skill to get at these parts.

Let me know what you find, we can go from there until this resolves.

Customer: replied 4 years ago.

The spark is ok.


I will return to the cabin in 1-2 weeks and will give you compressed air suggestion a try.


You mention that it takes some "mechanical skill" to get at the parts. Could you explain in more detail what you mean by that? There seems to be a hole/opening at the bottom of the inside unit where the pilot light and ignition spark can be viewed through a small round viewing window.

Hello again, the round hole at the bottom should be sufficient access.. you were able to find that access... some people are not.... you will benefit from a bendable 1/4" copper tube or other means to reach inside and at all different angles... a rental air compressor set a 20 or 25 psig (pressure) will work best...

Let me know how it goes, we can proceed from there as long as you keep rating my advice positively I will keep the question open for you.

Customer: replied 4 years ago.


Customer: replied 4 years ago.

How do I find the way to rate the service?

Hello again, I will put up the ratings box now, and if you choose to rate my service so far *positively, I will hold the question open for any follow up that you might need later.


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