Dometic Brisk II dripping water inside.

[BobJones]

Sometimes I really have to wonder if it's ever worth helping people....

My neighbor has a 5th wheel with a single Dometic Brisk II on the roof. The weather has been hot so she's now running her AC. The complaint is that water spits on the floor when it's running.

I took the cover off and checked the evap drain troughs to ensure they were clear. They are. Water flows properly outside. The freeze sensor was stuck off to the side so I moved it to dead-center of the bottom by one of the tubes (on the assumption that it may be freezing up at some point and then melting resulting in water /evap freeze). Buttoned it back up and went inside.

Found out the the thermostat was goofy. It was not operating properly. Reset it and it started working better. But noticed that after powering on and off it would then begin doing strange things and behave inconsistently.

I told her that was a common issue and the cure was to upgrade the board and the thermostat as Dometic tends to repair their designs that way....btw, that speaks volumes about Dometic's design process....

I also told her that she was combatting several issues. The RV manufacturer only installed one AC unit and her unit should really have two (+30 feet). As such, in order for the AC to pull the inside temp down it has to be left on continuously in order to keep up. To make matters worse, the bedroom is upstairs about 5 or 6 feet higher than the rest of the unit, so you can imagine where all the heat goes (it rises).

In addition, the design of her roof is curved so the AC unit may be prone to spitting out water anyway as the AC unit does not sit flat. On top of that, on the Brisk II, the fan, when it's on high, blows a TON of air. I mean, it's a monster! So there is always going to be the possibility that, with that kind of air flow, it will blow some condensate through and you will get some water drops on the floor.

Anyway, I mentioned to her she needed a new thermostat and board regardless but that it may not fix her issue with respect to the water. It really depends on whether they (Dometic) changed the way the system operated (updated it).

Long and short. AC now works perfectly but it still spits some water. I checked the existing frost sensor and it specced out exactly as the new one so I left the old one in place.

What did I charge her? Nothing. Just the cost of the parts. What do I hear all day long? The AC is dripping water on the floor. I told her from the get go, before buying anything, that I did not design the AC system and she really should have had two roof mount units. Also, that the slope of the roof may be playing an issue as well as the massively powerful fan. That all of these things will play a role in the issue.

Sometimes I really wonder whether a person should bother to help others. The only solution I can see to her issues are that the unit should have had two AC units so that they can keep up and then they would keep the fan on low. But then...the design of the system is that if it detects evap freeze it will shut the compressor off and put the fan on high to clear the freeze which puts her back to the odd water spots coming in

Did I mention that I didn't design the system? Several times, before we ordered up the parts that were goofed anyway

Thanks for letting me vent from my unit with properly running AC that works well

[Dutchstar411]

Originally Posted by BobJones

Sometimes I really have to wonder if it's ever worth helping people....

My neighbor has a travel trailer with a single Dometic Brisk II on the roof. The weather has been hot so she's now running her AC. The complaint is that water spits on the floor when it's running.

I took the cover off and checked the evap drain troughs to ensure they were clear. They are. Water flows properly outside. The freeze sensor was stuck off to the side so I moved it to dead-center of the bottom by one of the tubes (on the assumption that it may be freezing up at some point and then melting resulting in water /evap freeze). Buttoned it back up and went inside.

Found out the the thermostat was goofy. It was not operating properly. Reset it and it started working better. But noticed that after powering on and off it would then begin doing strange things and behave inconsistently.

I told her that was a common issue and the cure was to upgrade the board and the thermostat as Dometic tends to repair their designs that way....btw, that speaks volumes about Dometic's design process....

I also told her that she was combatting several issues. The RV manufacturer only installed one AC unit and her unit should really have two (+30 feet). As such, in order for the AC to pull the inside temp down it has to be left on continuously in order to keep up.

In addition, the design of her roof is curved so the AC unit may be prone to spitting out water anyway as the AC unit does not sit flat. On top of that, on the Brisk II, the fan, when it's on high, blows a TON of air. I mean, it's a monster! So there is always going to be the possibility that, with that kind of air flow, it will blow some condensate through and you will get some water drops on the floor.

Anyway, I mentioned to her she needed a new thermostat and board regardless but that it may not fix her issue with respect to the water. It really depends on whether they (Dometic) changed the way the system operated (updated it).

Long and short. AC now works perfectly but it still spits some water. I checked the existing frost sensor and it specced out exactly as the new one so I left the old one in place.

What did I charge her? Nothing. Just the cost of the parts. What do I hear all day long? The AC is dripping water on the floor. I told her from the get go, before buying anything, that I did not design the AC system and she really should have had two roof mount units. Also, that the slope of the roof may be playing an issue as well as the massively powerful fan. That all of these things will play a role in the issue.

Sometimes I really wonder whether a person should bother to help others. The only solution I can see to her issues are that the unit should have had two AC units so that they can keep up and then they would keep the fan on low. But then...the design of the system is that if it detects evap freeze it will shut the compressor off and put the fan on high to clear the freeze which puts her back to the odd water spots coming in

Did I mention that I didn't design the system? Several times, before we ordered up the parts that were goofed anyway

Thanks for letting me vent from my unit with properly running AC that works well

I'd, in the mean time, put the fan on med or high and not on Automatic, to help keep the evap from freezing and to keep the moisture down. Did you check the crush on the gasket, maybe tighten down the unit a bit incase some water is getting by the main gasket, that was the case on one of my Dometics, Penquin II?

I hear you about doing favors... been there and done that as well. Most understand, and then again... "The AC is dripping water on the floor."

[Old-Biscuit]

Which way does the A/C Unit---roof slope?
Should be so that the Evap Drip Pan drains are on the downward slope so water in pan drains away from the evap coil/return air opening.

If it doesn't then NO WAY to stop water from drip pan to leak out ceiling grille

How was the Return Filter.....
Dirty causes icing up on EVAP
Drip drip drip

Is A/C Unit a 15K or 13.5K?
15K should be able to keep up/maintain inside temps to 78*F with HOT temps beating down on trailer
13.5K....nope

Granted ONE is not idea but workable if 15K and one turns it on in AM before temps start rising....afterwards is like chasing it/never catch up

(Take pain pill before one has pain)

[BobJones]

Originally Posted by Dutchstar411

I'd, in the mean time, put the fan on med or high and not on Automatic, to help keep the evap from freezing and to keep the moisture down. Did you check the crush on the gasket, maybe tighten down the unit a bit incase some water is getting by the main gasket, that was the case on one of my Dometics, Penquin II?

I hear you about doing favors... been there and done that as well. Most understand, and then again... "The AC is dripping water on the floor."

This is what I suggested to her. Manually set the fan to medium (if that setting exists) or to low. I also told her to close the bedroom door and isolate the 'upstairs' so that the AC has less work to do. I can tighten the gasket but I don't see it being the issue. The spitting is coming from inside the system, so to speak.

This is not a ton of water. This is the odd drop or so. Her floor is that fake wood (some kind of plastic) so it's not like it's going to damage anything so I told her to ignore it. The AC would actually dehumidify the unit anyway, it will pick up that small amount of water and send it back outside!

Up here AC use is seasonal and, even that, only used for perhaps two months of the year. A rational person would just put a towel down and forget about it and enjoy the cool air. But your point about the bolts is worth pursuing, after all, there's nothing to it and everything else has been done so 5 more minutes to exclude it is not a big deal.

[BobJones]

Originally Posted by Old-Biscuit

Which way does the A/C Unit---roof slope?
Should be so that the Evap Drip Pan drains are on the downward slope so water in pan drains away from the evap coil/return air opening.

If it doesn't then NO WAY to stop water from drip pan to leak out ceiling grille

How was the Return Filter.....
Dirty causes icing up on EVAP
Drip drip drip

Is A/C Unit a 15K or 13.5K?
15K should be able to keep up/maintain inside temps to 78*F with HOT temps beating down on trailer
13.5K....nope

Granted ONE is not idea but workable if 15K and one turns it on in AM before temps start rising....afterwards is like chasing it/never catch up

(Take pain pill before one has pain)

Roof slope, if viewed in profile, looks like a hump-back whale
What this means at the AC unit is that the front of the AC unit is sitting higher than the rear. You can see this when you look at the water in the trough, it is higher at the rear of the unit where the water spits out....so when the water level reaches equilibrium and starts to drain out the proper hole, the level at the back of the tray is always nearly overflowing.....THIS, I believe, is where the issue really lies. When you combine that with that incredibly powerful fan, it's no wonder some spotting occurs. The rear of the trough,where the water level is highest, is right next to the cold air outlet.

The return filter is cleaned, I made her wash it while I worked I don't believe there is an icing issue, per se, as airflow is always very high. I specced the new frost sensor against the old one and it was only off by 3/10ths of an Ohm. Bear in mind, the temperature on the roof is different then the temperature inside where I read the new one. As such, I told her to keep it as a spare as the existing one is working perfectly.

The unit is a 15K. But here's the rub. I told her to leave it on, 24x7, and to keep the doors and windows CLOSED. But she keeps monkeying with it, and using a thermostat is challenging for her.... So I set it to 23 (73.4f) and told her to leave it there. At night, the AC does not run as it's cool enough. Idea being, it will fire up in the AM and get caught up, but as you said, the trick is to keep it caught up because she only has one AC unit and it really should have had two.

Interesting to note, the fuse panel has a second breaker installed for the other, non-existing AC unit.

I repeated myself at least 5x about the fact that I did not design the system, that the slope of the roof is causing an issue and that it may well keep doing it, but...that her thermostat was goofed and that Dometic updates the operation/design through thermostat/board upgrades. PRIOR to ordering in parts. At one point she told me to stop repeating myself! She understood.

And yet....here we are! Which brings me back to my first point, should a person even bother to help someone?

The good news is that her entire control system is new, it's perfectly installed, I checked everything with a multi-meter- its like a new system and the operation is no longer buggy, ie, the thermostat now works consistently. But as I mentioned to her many times, the issue really is that the unit should have had two AC units, even then, the slope of the roof would be problematic, but it would probably work.

Nice to hear confirmations because at the end of the day you start to really wonder....

[BobJones]

It's funny, I was just thinking about it.....

When I saw the angle that the AC unit was on the first thing I checked was if the 5th wheel was level. I was, both front to rear and side to side.

I suppose a work-around could be to put a carpenters level on the AC unit and then lower the front of the 5th wheel until it reads that the AC unit is level. That should work around the slope of the roof, assuming the unit is not so off-kilter that it's annoying.

On the other hand, I think I've done my charity work for the week......

[Old-Biscuit]

The 'crush gasket' is a concern Only IF:
*It is Raining and water is dripping when raining
*The Hold Down Bolts are loose...should be finger tight then JUST SNUG
*40 INCH Pounds of torque ....INCH not Foot

A/C Unit front higher then rear...so drip pan is sloped towards the drain holes
Trough (pan) might be clean but drain holes clogged ---they are very small holes (1/4" -- 3/16")
I enlarged mine (1/2") so water flowed faster then collecting in pan

If crush gasket is tighten too much then drains could be too close to roof and be obstructed even when clean
S/B roughly 1/2" between roof and bottom mounting plate of A/C Unit


The above is JUST Information...cause I think you are DONE.....LOL

You can only 'help' folks that are willing/able to be helped
Some folks you can just not help

Don't give up helping folks...we're all in this together
And recognize those that you just can not help ..... help so much then move on

50A RV...2nd breaker for another A/C Unit.....probably re-wired to bedroom Fan for optional 2nd A/C Unit

[BobJones]

Just heard from the 'customer' and I use that term loosely, since I did not profit from the event Apparently the AC unit made a loud 'bang' and then water came 'pouring' out of the vent

'Customer' is prone to exaggeration has significant fear issues. Anyway, I went over, turned it on, set the fan to low and told her to re-read the email I sent to her a few minutes earlier;

"You have to leave it on all day and you can turn the fan to low or medium if it has a medium setting.

The water issue is caused by several things;

1) The slope of the roof makes the water build up at the back of the evaporator making it prone to spitting some water
2) The fan is very powerful, which is by design so that it blows a lot of cold air, problem is, it exacerbates the issue that the factory created with the slope of the roof
3) The unit should have had TWO AC units so that it can keep up.
4) You *have* to leave it on, 24x7, with the doors, windows and vents closed so that it can keep up. This is exacerbated by the fact that you only have one AC unit. Keep the bedroom and bathroom closed off so that you reduce the amount of work the AC has to do.

I wouldn’t worry about a rattle. I’m sure it’s nothing. As I said from the outset, I did not design the system, all I can do is fix what’s wrong within the scope of their design. When they designed the slope it put the AC unit on an angle. It really needs to sit flat. The issue is exacerbated by the powerful fan and the fact that you only have one AC unit so it has to run a lot more.

Those are your answers. I really don’t want to talk about it anymore. Maybe print them off so you can refer to them later."

You are right, I'm done!

Btw, AC unit does drain through the drain trough holes and it does run off the side of the roof. I did check that the holes were not obstructed etc. At the end of the day I have to come back to the original conclusion, when the factory mounted the AC on the side of a hill it would cause drainage issues that are exacerbated by the powerful fan they put in there. As for all the water that is apparently running out onto the floor, I've never seen it. All I've ever seen are intermittent spots on the floor, the kind that most folks, under the circumstances, would just ignore.

I did just go over and set the fan to low (it has no medium). I doubt it will change anything though for this reason, with the fan on low the evap will be more prone to freeze and cause the circuit to cut the compressor and put the fan on high to melt/dry it out. Which means we are back to the same design issue. Rinse and repeat

[Dutchstar411]

Originally Posted by Old-Biscuit

The 'crush gasket' is a concern Only IF:
*It is Raining and water is dripping when raining
*The Hold Down Bolts are loose...should be finger tight then JUST SNUG
*40 INCH Pounds of torque ....INCH not Foot

Crush gasket should be at 1/2 to 9/16th inch in height once torque is completed, 40-50 inch pounds. Excess water on the roof, at least on my Newmar can accumulate on the side of the AC's quite often since the roof is not at a steep slope and also water is never completely running off down the gutters, it pools when parked. Newmar uses lag bolts to hold the AC unit to the roof, not the typical setup using a sandwich setup. In the OP's case the fifth wheel was just mentioned and if the AC is already at a slope under 15 degrees, (over is not recommended,) water runoff should not be an issue. Her problem is the unit is freezing up, either by running it way too long or there isn't enough separation between the intake and the exhaust of cold air within the unit. I would also lower/place the freeze sensor down more.

Bob, I would highly recommend another RV service TECH that would charge her for every service call. Maybe she would be more appreciative of what you've done for her already.

[Dutchstar411]

Just saw this article here on IRV2.com:

https://www.doityourselfrv.com/rv-ac-repair/


Evaporator fins should be clean and free of dust and debris to function efficiently. A harder working AC unit can freeze up if the evaporator fins are blocked and not allowing moisture to be removed.

The warm air intake side of the ceiling-mounted AC unit has to be sealed from the cold air exhaust side or it can cause condensation and consequently freezing up of the evaporator.

If you are in a very humid area it can be difficult for your AC to keep up with the removal of humidity causing extra condensation and freeze up.

Running your fan on high and adding a dehumidifier or air dryer to your RV will both help prevent freeze-up in these conditions.

[BobJones]

Originally Posted by Dutchstar411

...In the OP's case the fifth wheel was just mentioned and if the AC is already at a slope under 15 degrees, (over is not recommended,) water runoff should not be an issue. Her problem is the unit is freezing up, either by running it way too long or there isn't enough separation between the intake and the exhaust of cold air within the unit. I would also lower/place the freeze sensor down more.

Bob, I would highly recommend another RV service TECH that would charge her for every service call. Maybe she would be more appreciative of what you've done for her already.

I'm going from memory but I am pretty sure the slope is away from the drain holes. I had already moved the frost sensor to dead center bottom touching the copper tubing and I also checked the OHMS on it against the new one. It's not freezing.

The issue really seems to be threefold;

1. The AC unit is on a slope - pretty sure it's away from the drain holes
2. The fan is very powerful and blowing some of the condensate into the exhaust at times.
3. The unit should have had dual AC units so that the single unit does not have to run continuously. It does not seem to ever catch up due to the size of the 5th wheel

But I do agree, she should call someone in, and, if they are astute...they will come to the same conclusions.

Don't get me wrong, it can be fixed, a few extra drain holes and tubing of just the right size would likely address it. But at this point, I'm not interested in doing anything more

What is interesting is that I did a search a couple of hours ago with the keywords Sundance and AC dripping and found a lot of posts from people doing all sorts of weird things to address it but none of them seem to have realized that the three points above are converging on them Btw, it's not even that humid out but from the emails I am getting, there are literally GALLONS of water coming out! Despite the fact that it is actually draining out the side as it's supposed to....

[Dutchstar411]

I don't blame you Bob.

[BobJones]

Well, here's an update to the story. She called in an AC guy and he spent 3 hours on it from the time his vehicle was there....

In the end he said it was the roof gasket So he tightened that up. She then sent me an email exclaiming that he fixed it.

15 minutes later she sent one back saying it was still leaking. So she called him back. She then got him to install the new frost sensor, you know, the one that I tested against the old one that was only off by 3/10ths of an Ohm......

And of course, there's water again since the original frost sensor was just fine (which is why I didn't bother to replace it).

He's now telling her she needs a new AC unit because the coils are shot........

What did I tell her?

"You have to leave it on all day and you can turn the fan to low or medium if it has a medium setting.

The water issue is caused by several things;

1) The slope of the roof makes the water build up at the back of the evaporator making it prone to spitting some water
2) The fan is very powerful, which is by design so that it blows a lot of cold air, problem is, it exacerbates the issue that the factory created with the slope of the roof
3) The unit should have had TWO AC units so that it can keep up.
4) You *have* to leave it on, 24x7, with the doors, windows and vents closed so that it can keep up. This is exacerbated by the fact that you only have one AC unit. Keep the bedroom and bathroom closed off so that you reduce the amount of work the AC has to do.

I wouldn’t worry about a rattle. I’m sure it’s nothing. As I said from the outset, I did not design the system, all I can do is fix what’s wrong within the scope of their design. When they designed the slope it put the AC unit on an angle. It really needs to sit flat. The issue is exacerbated by the powerful fan and the fact that you only have one AC unit so it has to run a lot more.

Those are your answers. I really don’t want to talk about it anymore. Maybe print them off so you can refer to them later."

But, apparently the AC guy told her I did good work....so there's that I'm pretty sure I'm going to find she's ordered up a new AC unit to fix the problem.....shame she didn't show him the email I sent her explaining it....

[Dutchstar411]

The sad thing is the guy she called got paid for at least 3 hours while your good effort was for not.

The good news is she hopefully is out of your hair and now knows for sure, you were RIGHT ALL ALONG

Just a question, because of that combined design flaw, could a thin membrane filter be put within the cold discharge air box to absorb some of those droplets? With the air flow drying them before they hit the floor?