Roof top AC

[Vt_Rv]

My rooftop Coleman AC blows cool but not cold air. I'm told its a closed system that can't be recharged.

Headed out west this summer and will need AC.

RV repair is suggesting I replace my current unit with a Dometic Brisk Air 1500 BTU AC.

The unit sells for $857. Is this a good idea or are there other options?

[wa8yxm]

Vt Rv wrote:
It is a ducted unit. I've cleaned the inside filter but haven't gotten up and removed shroud. What would I be cleaning? Is it a matter of blowing out the fins?

You should remove the outer cover (Shroud) then there are two inner covers, one covers the condenser and one the evap..

Before you go "Topside" remove the indoor intake filters and examine the evaporator coils if you can from below using a small flashlight to illuminate the coils.. IF they are clean, then up on the roof you can leave that cover alone.. IF NOT, you will have to figure out how to pull it, instrucitons vary.

Now remove the needed screws etc to remove the CONDENSER cover (The otside coils) and look into the area where the fan lives to get a good view of the real problem.

YOu may need to remove the fan,, THIS may involve removeing the other cover.. Or you may be able to loosen the lock bolt or clamp and move it up or down, or remove it, Or you may not need to remove it, all depends on many things.

Using a brush, clean as much as you can off those coils.

NOW hose them out.

Restore fan if needed

Clean everything else that can stand it that is up there.

I have never seen lubrication ports.. but if you got 'em, use 'em.

IF NEEDED.... Comb out the fins on the coils (Hopefully not needed)

And finally restore all covers.

Should work better now.

[dougrainer]

How are they going to interface the RVP controls to the Dometic???? Kind of hard to do. Stick with the RVP replacement. Doug

[Altern]

crasster wrote:
You can add a port if you are comfortable using solder and a torch, but I prefer mapp gas and brazing it with a copper rod. Once you have a port, you can get a vacuum tool to create vac pressure in the line and recharge it yourself. (works for autos too).

IMHO there are so many things about this post that contains poor or mis-information one hardly knows where to start.

[jswalls110]

Here is how I fixed mine.

http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/26175172.cfm

[deandec]

Up top you would cleanthe coil.

Just did my home units last week with foam ac cleaner from home depot.

[crasster]

You can add a port if you are comfortable using solder and a torch, but I prefer mapp gas and brazing it with a copper rod. Once you have a port, you can get a vacuum tool to create vac pressure in the line and recharge it yourself. (works for autos too).

[rgatijnet1]

In a ducted unit it is important to make sure that the unit is sealed to your duct, with no leaks. This can be seen by taking off the inside cover and looking for loose tape, or other means used to insure that the cold air from the AC unit is going directly in to the duct and not leaking outside or into the roof frame.

[bgum]

At PPL in Houston the same AC costs $425 plus installation or shipping.

[Vt_Rv]

It is a ducted unit. I've cleaned the inside filter but haven't gotten up and removed shroud. What would I be cleaning? Is it a matter of blowing out the fins?

[Lt46]

They are correct when they say it's a closed system, however some have had fittings brazed into the lines so that recharging is possible. This doesn't fix the leak but does allow for recharging.
I've read where some posters have been disappointed with the cooling power of newer AC units. I have no 1st hand knowledge but it might be worth some research by you to see if it's one AC manufacturer in question or all of them.
I bought a used Coleman off EBay a few years ago and it was running strong when I sold my TT. Just another option.

[MountainAir05]

have you clean the unit. Requires to get on top to do. Is it a ducted or open system. Checked filters. Yes you can recharge but the cost will be high. Even to check the charge you have to install a port. The rest is easy. Finding someone who will work on it could be an issue. True it is easy to replace.