Problem Oasis water heater

[Steve4059]

Hi all! We’re full timers in a 2022 superstar 4059
We’ve got an Oasis water heater that’s been working like a charm until now. The fault lite started coming on. When I went outside to take a look at the unit I found the low water light on.
I don’t know how to check the coolant level?
I kinda thought that this was a closed loop system . Don’t know enough to be able to diagnose this properly. Anyone with some knowledge of this system would be greatly appreciated.

 

[Neal]

Should be a clear plastic bottle. Okay, white opaque. Probably in aft of your coach or in chassis battery compartment. It will say oasis on the side.

Amazon product ASIN B09NS16W67

 

[Steve4059]

Should be a clear plastic bottle. Okay, white opaque. Probably in aft of your coach or in chassis battery compartment. It will say oasis on the side.

Amazon product ASIN B09NS16W67

Thanks for the info! I did find one next to the boiler’s fuel filter. Can’t see ‘Oasis’ but it is dry. I’m going to fill it and see if that solves the problem.

 

[Neal]

I suggest posting a picture or check Newgle. If you put fluid in the wrong tank it could be a very costly mistake. Until sure don’t put fluid in a tank. Maybe call Newmar or ITR first.

 

[Steve4059]

OK so I put more coolant into the dry tank. I turned everything back on. Now it seems that I have hot water but as soon as I try to turn on the hydronic heat (the floor heaters) the heater module fault light comes on. The unit has 700 hours on it and it’s a year old. Do I need to replace a circulation pump? Flush the coolant? Also, now that I have just the water heater going, the heater module and zone fault lights seeem to be glowing a bit???

 

[Neal]

Next to your OASIS unit is a silver panel with lights. Any red lights showing? Take a pic if needed.

I believe floor heat is an electrical system that is not related to OASIS.

 

[Steve4059]

I suggest posting a picture or check Newgle. If you put fluid in the wrong tank it could be a very costly mistake. Until sure don’t put fluid in a tank. Maybe call Newmar or ITR first.

Hi all! I took a chance and filled the empty tank about 3/4 full. After listening to the pump cycle on and off about 10 times I saw the level in the tank I just filled go down to about >1/3. Now the unit is working!!even when I turn on both zones of floor heat and the water heater!(AC) don’t know if there’s a way to prime the system or an easy way to flush it out but this Newman newbie will definitely study the ins and outs of diesel/AC water heaters a whole lot more!

 

[Steve4059]

Next to your OASIS unit is a silver panel with lights. Any red lights showing? Take a pic if needed.

I believe floor heat is an electrical system that is not related to OASIS.

I did see that panel above my Chinook heater.
There was a switch on top of it that seemed to toggle the coolant pump on and off. No red lights on the panel, just the ‘low water’ led glowing on the array on the tank. After filling the tank up quite a bit I finally got the pump to start sucking fluid from the plastic tank! Now everything seems fine!
(For now!)

 

[Neal]

The switch on top is an override and should be OFF. Otherwise all pumps run continuously which is a failure/emergency mode use only.

 

[Steve4059]

Yes, I was aware of that from reading the small owners manual. I actually used that switch to get the coolant flowing through the heater lines.

 

[Rich W.]

my question would be where did the fluid go?

 

[Steve4059]

Well… my first answer would be evaporation. When I first found the tank I also noticed that this is an open system. The coolant tank has a line at the bottom for the system to draw upon and it also has another tube at the top in case the coolant gets overheated and needs to drain away to prevent over pressurizing the heat system . I assumed the heated coolant would slowly evaporate over time. Probably dependent on how you use the heat system.

 

[JRS]

Hate to say this but I'm guessing you have a hydronic fluid leak. You should very rarely have to add fluid to your system. We had a slow leak that Newmar techs couldn't find at first. When they changed our black tank sensor system to a pressure type, they went behind the pegboard bay to the tank and noticed damp insulation in the area. They found the leak....
Unfortunately I don't know where your fluid reserve tank is... Ours is in the engine bay.
Here's the fluid that's used in my rig.

Century Chemical Aqua Hot heating systems Transfer Fluid RV

Aqua Hot boiler anti freeze RV heating systems

www.flemingsalesoem.com

A DS friend said not to mix colored fluid. He reported he added red fluid to his and it jelled his fluid. But I've also read that mixing isn't an issue..... All I know is I carry the exact fluid in the link above.

 

[Steve4059]

Funny you should mention the black tank sensors.
We’re having the same problem with ours!! We’re full timing in our superstar and have yet to get our sensors replaced. My wife has been turning on the hydronic heat for about a year before we had the ‘low water’ light come on. Our feeder tank is located next to our passenger side fuel tank. I filled the tank, then turned on the furnace for a day and watched the tank slowly burp down.
Filled it again and watched it burp a little more.
Filled once more and…… so far so good!
We will eventually get our black tank sensors replaced and I WILL have them check those hoses at that time! Thanks so much for the heads up! Unfortunately after looking at the hydronic hoses coming out of the unit I personally think that they’re not right for the application. It seems to me that the reason the fluid becomes dark is because the hoses are degrading on the inside making the fluid turn black. I know that it would be difficult but I think that the red type heater hose( the kind that’s used when you get the heater core replaced in your car) would be more resistant to degradation from cycling on and off.

 

[Roadglide117]

Hi all! I took a chance and filled the empty tank about 3/4 full. After listening to the pump cycle on and off about 10 times I saw the level in the tank I just filled go down to about >1/3. Now the unit is working!!even when I turn on both zones of floor heat and the water heater!(AC) don’t know if there’s a way to prime the system or an easy way to flush it out but this Newman newbie will definitely study the ins and outs of diesel/AC water heaters a whole lot more!

That switch on top is a way to run your system for 3-5 minutes and get any air pockets out

 

[Roadglide117]

Hate to say this but I'm guessing you have a hydronic fluid leak. You should very rarely have to add fluid to your system. We had a slow leak that Newmar techs couldn't find at first. When they changed our black tank sensor system to a pressure type, they went behind the pegboard bay to the tank and noticed damp insulation in the area. They found the leak....
Unfortunately I don't know where your fluid reserve tank is... Ours is in the engine bay.
Here's the fluid that's used in my rig.

Century Chemical Aqua Hot heating systems Transfer Fluid RV

Aqua Hot boiler anti freeze RV heating systems

www.flemingsalesoem.com

A DS friend said not to mix colored fluid. He reported he added red fluid to his and it jelled his fluid. But I've also read that mixing isn't an issue..... All I know is I carry the exact fluid in the link above.

ITR told me it didn't matter, but it will change color more like brown that alarms people

 

[SteveMA]

Check the fittings on the top of the Oasis boiler for boiler fluid (wet or crusted). There is a known problem with these being loose and they leak. We had fluid around the fittings that I would wipe up - after a few times did some research and found that these may not have been installed correctly at factory. Pinching off the hoses and cleaning/redoing the connections seems to have stopped our 'slow' leak. (Prior to this I was adding fluid every few months, but could not find a leak anywhere else)

 

[Roadglide117]

Check the fittings on the top of the Oasis boiler for boiler fluid (wet or crusted). There is a known problem with these being loose and they leak. We had fluid around the fittings that I would wipe up - after a few times did some research and found that these may not have been installed correctly at factory. Pinching off the hoses and cleaning/redoing the connections seems to have stopped our 'slow' leak. (Prior to this I was adding fluid every few months, but could not find a leak anywhere else)

Thanks Steve.....my leak was right at the circulating pump after I changed out pump. Think I was to paranoid how tight to tighten since pump is plastic and it has a brass adapter that screws on. Not leaking at moment.

 

[Steve4059]

Check the fittings on the top of the Oasis boiler for boiler fluid (wet or crusted). There is a known problem with these being loose and they leak. We had fluid around the fittings that I would wipe up - after a few times did some research and found that these may not have been installed correctly at factory. Pinching off the hoses and cleaning/redoing the connections seems to have stopped our 'slow' leak. (Prior to this I was adding fluid every few months, but could not find a leak anywhere else)

Thanks so much for your suggestions!
Since I re filled the system I have been monitoring it as much as I can. Keeping an eye on the bottle fluid level (it burped twice) as well as looking for evidence of leaking along the system.
So far, so good! Kinda wish that the fluid would flow through some sort of changeable filter