Horizontal Exhaust Vent

[dannykoos]

Hello. I purchased a foreclosed house back in October. I have an inground pool, surrounded by a sunroom. The pool equipment is in the basement. There is also a natural gas pool heater. The heater works just fine. My problem is with the vent/exhaust. The vent/exhaust is a horizontal run to get outside...well, it goes up about three feet, then horizontal through my basement crawl space. Right before the exhaust vents to the outside, it goes through what looks like a fan of some sort. I would call it a "booster fan". After going through this fan, the vent goes another foot or two, then to the outdoors. This fan is not running. There is an on/off switch (just like a light switch) that looks like it controls this fan. The fan does not work when switch is in either direction. There are also two wires (smaller gauge than home electric wire) that go back to the heater...I am guessing this may be a way for the heater to tell the fan to kick on. My question is, how common are these fans? Are they expensive?

[HayZee518]

it is a squirrel cage booster fan costs about $17 from grainger's. when the ignitor turns on the booster is also supposed to kick in.