wiring diagram for blowers

[phillyg]

Just looking for a simple wiring diagram for two blowers on a switch. I could only locate one old blower in the boat and the wires were disconnnected and I could not get any voltage indicated. Rather than trying to salvage the existing wiring, I can run new wires. I installed two new blowers, one on each side. The switch lights up when turned on so I know it is getting voltage. I just don't know if I should run the wiring to the blowers in parallel or series and whether I should put a fuse in line, and if on the positive or negative side.

Thanks

 

[Bondo]

Re: wiring diagram for blowers

Ayuh,... Run the (+) lead from the switch to the blower(s) then the ground to the grounding buss...

Why 2 blowers,..?? 1 is enough to circulate the air...

 

[NYBo]

Re: wiring diagram for blowers

In other words, they are wired in parallel; it is standard practice to fuse the positive lead. The fuse goes goes between the battery and the switch.

I will repeat Bond-o's question: Why two blowers? Are they both installed to pull air out of the engine compartment like they are supposed to?

 

[phillyg]

Re: wiring diagram for blowers

Okay thanks. I only found one blower in the engine compartment so maybe that's all it had originally. It appears, however, there are 4" hose connectors behind the louvers on both the port and starboard, so I though two blowers were needed. Anyway, one working blower is better than what I had, i.e., none.

 

[Silvertip]

Re: wiring diagram for blowers

In order to properly evacuate the engine bay, the blower exhausts air from it, but that air needs to be replaced with fresh air so the other hoses are probably for that purpose. And blowers are never wired in series -- nor are most other accessories. The path is battery positive, to fuse panel to switch to blower then blower ground.

 

[NYBo]

Re: wiring diagram for blowers

In order to properly evacuate the engine bay, the blower exhausts air from it, but that air needs to be replaced with fresh air so the other hoses are probably for that purpose.

Not probably, definitely (as long as no one monkeyed with the factory setup.

Blowers must be set up to exhaust fumes not pull in fresh air. If set up to pull in fresh air, the compartment will be pressurized, sending fumes out of any opening, including into any other connected area. Not good, and a violation of the regulations.