Gas Heater Slow to Ignite

[Poconos]

The spiders and probably other critters poolman is referring to wind up in the burners and gas manifold. By the time the gas hits the burners it is at a really low pressure so it doesn't take much to mess up or block the gas flow. Never took them out of a pool heater but I suspect the burners themselves should be easy to remove. Once you get them out you'll see how they are vulnerable to obstructions. Once they do light if you can look inside you may be able to see if the flames are steady, even, and blue with orange tips. I think you want the flame tips to be slightly orange or yellow. Too much air and the flame is blue, too little and it turns yellow or orange indicating incomplete combustion. The owners manual should tell you how to adjust the air vents to get the right gas/air mixture.
Al

[jsnyder2914]

Update:
My spa heater that was taking a few minutes to ignite and heating the water perfectly as recently as last week will no longer ignite at all. Even after 30 minutes, nothing happens.

Going back to the earlier replies, now that it suddenly won't ignite at all, what should I look for, and how easy is it to get to?

A few years ago, I had a similar problem, and the repairman said there was a tube going from the manifoild to the pressuyre switch which was clogged. Once he unclogged it, it worked fine. Where is the tube and pressure switch located, and is it something that I can safely test and/or replace?

Thanks again...