I have a 98 patriot last summer Kevin Lampbert did a swap for a rebuilt hurricane box in my coach and I am curious why they switched yours to an Oasis? Maybe because you said it was noisy? Mine is a bit noisy but I do have one screw missing on the bottom of the box and I get a vibration from that. I love the hurricane I hope Ittr does not quit manufacturing that model they put an awful lot of them in fishing boats. I thought the oasis was a smaller less powerful unit. Their web site last summer mentioned switching units for a rebuilt one. Nothing about switching to Oasis.
I'll try to recall Gary. I visited them in October, 2013, after having purchased the coach in September. I'd already had a muffler shop weld the exhaust connection to the Hurricane, and my next step was to have them "fix" its problems.
They got to work on it, and while they were taking it apart discovering the deferred maintenance, Kevin mentioned the Oasis (larger unit) which couldn't fit into the space, he also told me the Seaward Water Heater was almost new, which I already knew from the previous owner - so I knew I could resell that part rather than junk it.
He then mentioned the cost of the maintenance and that there was some part, not sure what it was, that they were running out of, and that once they ran out, I'd need a new controller board (which was about $600 or $700). So, with that and the deferred maintenance, the total cost so far without going further was going to be about $1500 for my trip to see them (if I wanted the board upgrade - which I figured I'd need sooner or later).
This hurricane couldn't heat the coach with electric power, and that was a feature I was interested in to the extent that I'd called Jim Rixon's company about adding their Comfort Hot 1500W electrical apparatus to the Hurricane. The quote from Rixon was at least $2000, and I think he might have said $2500.
If I'd done the maintenance for $1500, then added the electric element of Rixon's that would be $3500, so it wasn't a huge leap moneywise to just go ahead and make things new by upgrading to the Oasis Combi. As for quieter, the literature on the Oasis Combi said it was very quiet, so knowing how loud I'd already heard the Hurricane to be, that was enough for me to say, let's just start fresh.
So, to answer your question, it was a combination of things - I had no idea how much longer the Hurricane would last so the last $1000 or so spent ($1500 + $2000 + $1000 = $4500) was sort of insurance going forward (having a brand new boiler) - not to mention its BTU rating was higher than the original Hurricane and could be supplemented by the 1500W (6500 BTU) element imbedded in it. It also fit the existing cabinet with space overhead to spare versus the Hurricane with Seaward Heater. Just seemed like a good idea to me, but I continue to be disappointed with the noise it makes. And that's why I was asking if others had upgraded to the Combi and what kind of noise their Combi makes.
I just returned to the ITR website, and it appears that some pages are outdated, as an example -
http://itrheat.com/products/hurricane-heating-systems/ which talks about a Hurricane II Combi. I don't think they name it Hurricane, it is now Oasis. The smallest unit outputwise and physically is this -
http://itrheat.com/wp-content/uploads/2011/07/Oasis-Zephyr-Bro-LR2013-.pdf - then the Oasis Combi here -
http://itrheat.com/wp-content/uploads/2011/08/Oasis-Combi-Bro-Beach-LR-.pdf and the largest (which wouldn't fit in my coach due to depth) here -
http://itrheat.com/wp-content/uploads/2011/08/OASIS-CH50M-Brochure-LR.pdf Kevin said that the BTU ratings on the original Hurricane was overstated but that the Combi's output was absolutely as stated so it was better.
The system performs as advertised but was simply louder than I'd imagined. I had it back to ITR a couple times to try to address the noise and I believe Kevin put some insulation into the cabinet - maybe he thought the problem was inner vibration of parts - and he gave me some sound deadening material that I have since placed on the sides of the cabinet, but I am now thinking of placing some "Anti-Vibration Pad" (neoprene) -
http://www.amazon.com/gp/product/B000OQTV2I/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1 - beneath the unit and behind it so that the vibration/noise is cut down. I think its the resonance from the sheet metal cabinet which intensifies the noise.
Before I did so, though, I'd thought I'd check with others, but evidently, no one else has an issue according to Tom's and Dave's postings (but Dave has an Aquahot - no fair!). Not sure right now how I am going to lift the unit up to place the neoprene beneath it, but I do think I can pull it slightly forward so that at least a can fit a piece behind it.
I hope I answered your question in all of that. My wife says I write so much that I get lost in it.
Mike