Question Using Coolant?

[Texas Clodhopper]

Most likely a defective HX in your Oasis. I assume you could replace only the HX. Brazed plate HXs sometimes fail this way.

I talked to Brian at ITR, and he said it's cheaper to replace the unit because the labor to repair the HX is a killer.

 

[osuallen]

I talked to Brian at ITR, and he said it's cheaper to replace the unit because the labor to repair the HX is a killer.

I wondered if that would be the case. Do you have the Chinook or the CH50 and DM 12

 

[turbopilot]

The oasis uses a 3 layer flat plate heat exchanger (HX). There are several sets of the 3 layers stacked (6 if I recall correctly) . The HX contains independent passsages for engine coolant, Oasis fluid, and domestic water. If driving in the winter and you turn on the oasis burner, the engine will furnish most/all the heat via the engine coolant running through the HX and heat transferring to the oasis fluid across the plates. If you install an optional pump, you can have engine preheat from the oasis via the same but reversed process.

Interesting. I my three years owning a Class A Newmar I was not aware engine coolant made a pass through the HX too. What a complex system. What could go wrong?

 

[Texas Clodhopper]

I wondered if that would be the case. Do you have the Chinook or the CH50 and DM 12

CH50 and DM12

 

[osuallen]

Interesting. I my three years owning a Class A Newmar I was not aware engine coolant made a pass through the HX too. What a complex system. What could go wrong?

Brazed plate HXs like this are very common. They are typically very reliable, but can fail on occasion.

 

[osuallen]

CH50 and DM12

That would probably be easier than a Chinook and no big deal 30 years ago, but I dont fit in small tight spaces like I used too.

 

[DennisT]

How is engine coolant loss related to your OASIS if that's what I'm looking at? Also, that is one messed up fitting when compared to the others.

Doesn't OASIS use the hydronic heating fluid vs engine coolant?

There is a loop that uses engine coolant to heat the oasis fluid. Should be valves to shut this loop off if you don’t want it flowing.

That exchanger and loop are separate from the oasis fluid and water portion.

 

[DennisT]

Interesting. I my three years owning a Class A Newmar I was not aware engine coolant made a pass through the HX too. What a complex system. What could go wrong?

That was one of the items discussed at the “Newmar Academy”. It led to some discussions about having engine coolant flowing through there

 

[Neal]

I would much rather have a design that routed the oasis fluid through the engine area instead of touching my critical engine coolant and adding risk for leaks or contamination with the OASIS system. Not thrilled with whoever thought of this idea.

 

[MemoriesByTheMile]

I would much rather have a design that routed the oasis fluid through the engine area instead of touching my critical engine coolant and adding risk for leaks or contamination with the OASIS system. Not thrilled with whoever thought of this idea.

If the risk is too much the you can install a couple valves close to the engine on the coolant loop.

As part of my check list I have checking oasis hoses at the distribution box. Had some leaks a few years ago. Since addressing those leaks haven’t had any issues.
Don’t want to leak boiler fluid or coolant fluid. We also carry extra of each fluid.

 

[DennisT]

If the risk is too much the you can install a couple valves close to the engine on the coolant loop.

As part of my check list I have checking oasis hoses at the distribution box. Had some leaks a few years ago. Since addressing those leaks haven’t had any issues.
Don’t want to leak boiler fluid or coolant fluid. We also carry extra of each fluid.

Should be valves installed already to shutoff that loop, if desired. According to what they put out during the Academy class.

 

[MemoriesByTheMile]

That would be great if Newmar did that.
When we had our leaks fixed on our Renegade we had valves installed on the lines they had to fix to make any future fix easier. But this of course means we haven’t had any issues since.

 

[Neemer]

Should be valves installed already to shutoff that loop, if desired. According to what they put out during the Academy class.

Did they say where they are located?

 

[DennisT]

Did they say where they are located?

Depends on the coach. Still have to track mine down on our superstar.

Once I locate ours I’ll update - whether closer to engine or Oasis.

 

[Texas Clodhopper]

When I replace my Oasis, I will confirm that there are valves or if I can simply not connect that hose - if that's an option. I don't need hot water while on the road and generally don't travel in cold enough weather to need the furnace running.