Rusting helm A/C? Webasto FCF unit spitting rust at me.

[Flot]

A few years back I retrofitted a Webasto FCF platinum A/C unit to provide helm air on my 330. I effectively installed this exactly the way Grady does, with the unit and intake under a seat, and used the oem grady panel for air outlet that blows across the cabin doorway at the helm.

It would be essentially impossible for the unit to get salt spray into it, although some (fresh) water could land in the intake or exhaust vent when I'm washing the boat etc.

Well.. a year and a half ago the unit started spitting rusty water on me (out of the vent) when I first turned it on, which was annoying but I managed. Now that has progressed to high speed flakes of rust being shot out of the air vent, which is not so comfortable.

Anyone had anything similar happen? I assume it is either the blower wheel or blower housing that is rusting, but it is going to take me a couple hours of contortion to get it out. I reached out to webasto's tech support email last year and got a "we've never heard of that" which seems.. unlikely.

 

[DennisG01]

The blower is attached to the condenser unit? That's awful close to the condensate tray. I would imagine that if it's not setup to drain well, or the drain is clogged, then the tray stays full of water and the fan is pulling in very moist air all the time. Especially with that spurt of water that you said.

 

[Flot]

I was able to remove the unit entirely and disassemble. Yes, the blower is basically attached to the evaporator (just like it is in your home AC unit), but I can see how the little bit of condensate water wouldn't really matter. As far as I can see the problem is that when I wash the boat, small amounts of spray go INTO the duct outlet, and eventually collect in the blower assembly.

I'm going to call this 50/50 my fault and bad design, but what is puzzling me is that I see all kinds of helm A/C stations and I assume people less careful than me would certainly spray water into them all the time...

 

[DennisG01]

but I can see how the little bit of condensate water wouldn't really matter.

If it drains properly, yes, no issues. But if the tray stays fuller it "could" cause issues - granted they would be cumulative, not immediate.

But, back to what you think is the culprit... can you route the ducting "up" as it leaves the backside of the vent? Even just a little bit would do it. Or, find a low spot in the ducting (before it gets to the fan) and put a small hole in it on the bottom side to drain water. Of course, you'd have to make sure to either make sure the drain water drains to an OK spot, or collect it and re-route. Hard to say exactly what to do without seeing things first hand - but it's sounds like you're pretty handy and maybe that at least gets you going in the right direction?

 

[Flot]

If it drains properly, yes, no issues. But if the tray stays fuller it "could" cause issues - granted they would be cumulative, not immediate.

But, back to what you think is the culprit... can you route the ducting "up" as it leaves the backside of the vent? Even just a little bit would do it. Or, find a low spot in the ducting (before it gets to the fan) and put a small hole in it on the bottom side to drain water. Of course, you'd have to make sure to either make sure the drain water drains to an OK spot, or collect it and re-route. Hard to say exactly what to do without seeing things first hand - but it's sounds like you're pretty handy and maybe that at least gets you going in the right direction?

When I took everything apart, mine clearly had 2" of water sitting in the blower assembly for some time. I suspect the very first time was after a hurricane we had where I took off the eisenglass - outside of that, it oculd have been my detailer one year, could have been some other mishap, who knows.

In any case, what I have learned is, if water goes in the outlet vent, it has no way out. This was easy enough to fix, I ground down and then epoxy painted over all the rusted metal, and drilled drain holes in the blower assembly that thankfully don't whistle or anything like that. Any water that goes in now won't have a chance to pool badly enough to do any more damage.

I have also taken the prudent move of removing the grate and stuffing a shop towel into the vent when I'm not using it (which let's be honest is 355 days a year).

I'm more annoyed with Webasto, if they had simply replied to my email 18 months ago with a "yes, you're right, whatever you do don't let water get into the A/C outlet because inevitably it will cause rust in the blower" I would have resolved this problem a lot earlier. So that's my public service announcement for the forum.

In my case, because this is a 2002 boat and was not set up for helm A/C, I was guessing at the right way to run it - and for efficiency I routed the blower hose as straight and short as possible, which in retrospect funneled water right into the blower. I don't have the clearance to make an upwards loop in the ductwork although that would also solve it. It's just not worth the effort now for me to try to redo all of that, but I'll keep an eye out for a newer 330 to see exactly what the factory did.