Many older homes have furnaces with pilots that burn around the clock to fire up when heat is needed. Newer models have no pilot light; instead, they use spark igniters that come on only when burners need to light. They then turn off until needed again. But if everything is working OK, and the heat won't come on, it might be the igniter; you'll need to test it. Sound risky? It's easy. Look where the pilot used to be. You'll see two wires, disconnect them, and test the igniter terminals with an ohm meter. A reading between 50 and 100 ohms is normal. If it's way off, it's time to replace it with a new auto pilot igniter. And that's the On The House tip for today.