anyone know where i can get the plastic covers for the roof vents? all 3 broken 1978 28 footer. thanks Richard

Try here. I bought from them several times - very easy to deal with.

quote:

Originally posted by rp's barth:
anyone know where i can get the plastic covers for the roof vents? all 3 broken 1978 28 footer. thanks Richard

What kind do you have?

Richard,

I recently purchased two new Fantastic 4000 units to R&R on my unit. I also bought two of the vent covers that Rusty referred to above. (although twice the cost from CW

The instructions on the covers mention that they are not recommended for "high performance" fans. I don't know what the definition is, but the instructions mention Fantastic by name. They suggest another model of cover be used....I assume because of the free-air discharge capability.

Bottom line is that if your fans are deemed "high performance", the cover referred to here may compromise fan cfm capacity.....

In my case, since I've already purchased, I'm gonna try new fans without cover, then temporarily install cover and see if there's a noticeable difference.

SIDEBAR: I have a HEAVY layer of EPDM rubber roof, slopped up over the old fan flanges....Other than grunt & groan with a putty knife, is there a better way to remove it & prep surface? (heat/dry ice/solvent, etc?)

Addendum......If your fans are classed as "high performance", MaxxAir says to use this cover:

http://www.campingworld.com/browse/skus/index.cfm?deptI...f=51,16&skunum=13655

Naturally, it costs about 300% more.......

quote:

Originally posted by Lee:
The instructions on the covers mention that they are not recommended for "high performance" fans. I don't know what the definition is, but the instructions mention Fantastic by name. They suggest another model of cover be used....I assume because of the free-air discharge capability.

I was told by Fantastic that the Maxx cover was OK on low and medium, but was restrictive on high. I know one fellow who removed the internal screen and opened up the louver openings on the Maxx hood to improve flow.

quote:

I'm gonna try new fans without cover, then temporarily install cover and see if there's a noticeable difference.

That sounds interesting. How about making a water manometer out of clear tubing and taking some readings of pressure inside the hood? Suppliers of industrial blowers usually have a max static pressure rating for their fans, depending on motor heat dissipation abilities. Current readings and/or motor heat readings would also make it a fun science fair project.

quote:

SIDEBAR: I have a HEAVY layer of EPDM rubber roof, slopped up over the old fan flanges....Other than grunt & groan with a putty knife, is there a better way to remove it & prep surface? (heat/dry ice/solvent, etc?)

Solvent: I would try a rag saturated in gasoline first. I have removed silicone rubber by keeping a rag saturated with gasoline and in the shade. It took several hours. Given the antipathy of EPDM roof manufacturers toward petroleum distillates, I would expect gasoline to be worth trying. I know oil will soften EPDM, but it might be slower-acting than gasoline. But it is easier to keep in contact with the surface, as it doesn't evaporate. Heck, maybe gobbing grease up there and just waiting a week or so might be the easiest.

Mechanical: I have a Skil drill that has a setting for impact drilling and one for just impact. This makes the supplied putty knife power-driven. Pretty nifty. As far as hand putty knives, the more flexible ones work better on sealant. A Hyde takes a nice sharp edge.

The EPDM over the old vent flange can be hogged off with a stiff wire wheel, since you are not concerned with damaging the plastic flange underneath. The standard hardware store wire wheel may not phase it. Welding suppliers have the stiff ones for slag removal.

A wire wheel can be used on the roof surface, but you gotta be careful not to hit the aluminum too hard. It used to be taught to only use a stainless or bronze wheel. Regular steel will leave tiny molecules of steel in the surface of the aluminum and bad things will happen, corrosion-wise. However, given the lousy metallurgy of offshore metal suppliers today, I would not even trust a stainless brush any more. Go for bronze.


Heat/dry ice: Heat helps some. The combination of a heat gun and a sharp putty knife works fairly well. I would doubt that dry ice would help much. EPDM is touted for its low temp flexibility.

An alternative to the Maxx Air might be Ramble. By having side louvers, they claim 50% more air flow. Priced about the same as Maxx Air.

UPDATE: Opened up all the Fantastic 4000R and Maxxair vent cover boxes last night in preparation for the R&R of my two vents this weekend......

Found a tag tied to each fan that said:

"Note: never place a Maxxair style cover over, or filter on ceiling fan. Greatly restricted airflow & increased sound levels will occur."

Phone call to tech rep confirmed their recommendation, although he never-said-never.
But like Billh mentioned, high cfm settings will be compromised & noise greatly increased.

Consequently, I'm gonna cancel my plans for Maxxair cover use........So here's the deal....

They cost me $60.00 for the pair from CW (Item 10939), incl. shipping & Prez Club discount. They're still new in the box - just opened for inspection.

If you want them, the first $30.00 (or MORE!) donation to Dave to help with Barthmobile.com will get them to your front door, shipping prepaid.......Use PayPal on Homepage here & mention vents....We'll get your snail mail address via PM and get them to you right away!

Lee
Wash. DC
'78-24'