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Propane to Diesel Hydronic Conversion Primus to Aquahot, Webasto or Other

Posted: Sat Mar 02, 2024 6:45 am
by Panton
I am looking at solutions for the hydronic heating boiler and controls. Currently this bus is set up with a Primus 2490 propane unit. I have not even looked at it yet. I may actually be able to get it to work however,,,  unless I can find a parts source for the future I do not intend to spend any time on it. This seems to be the issue. Any thoughts appreciated if anyone has done such a conversion from Primus to another boiler. Thanks

Re: Propane to Diesel Hydronic Conversion Primus to Aquahot, Webasto or Other

Posted: Sat Mar 02, 2024 9:35 am
by rusty
I have an Oasis unit made in Canada. It is a diesel fired unit. I like it way better than the Aqua Hot that I have in my first bus. It is quieter and does not smell as bad. It does all the things an Aqua hot does.
Wayne 

Re: Propane to Diesel Hydronic Conversion Primus to Aquahot, Webasto or Other

Posted: Sat Mar 02, 2024 5:14 pm
by Panton
Thanks Rusty! I do have this link saved from my initial research. Any advice you can add? 

Currently the Primus is located on the passenger side on a nice platform under the rear tail light with easy access from the main motor hatch and the hinged tail light panel.  It would be easy to build a little manifold to pull and return diesel from the main engine feed lines.  All of the old AC has been removed on that side and compartments put in place right up to the frame rails so I have plenty of room and access to install and vent easily.  All the plumbing is there from the Primus so, I would be pretty far ahead of the game in relation to location prep and plumbing right off the bat.

https://itrheat.com/products/rv-trailer ... ng-system/

Re: Propane to Diesel Hydronic Conversion Primus to Aquahot, Webasto or Other

Posted: Mon Mar 04, 2024 9:06 am
by rusty
Here are the 2 Oasis units I have like them both the NE unit will probably be the one I would use. A little more compact.  I would make sure to keep as much engine heat off the unit. Not sure if a lot of heat is good for the unit.
20240303_101446.jpg
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20240303_101413.jpg

Re: Propane to Diesel Hydronic Conversion Primus to Aquahot, Webasto or Other

Posted: Mon Mar 04, 2024 10:00 am
by Panton
Rusty, I am sorry. I am unclear. Do you have 2 systems here or do these work together in some way. Is it in 1 coach or 2 separate coaches or did you swap one for the other. I don't quite understand. Thanks for you help!
 

Re: Propane to Diesel Hydronic Conversion Primus to Aquahot, Webasto or Other

Posted: Mon Mar 04, 2024 5:34 pm
by rusty
These are 2 different systems in two different coaches.
Wayne

Re: Propane to Diesel Hydronic Conversion Primus to Aquahot, Webasto or Other

Posted: Sat Mar 09, 2024 5:58 pm
by luvrbus
The Blue Bird people use a lot of Primus systems check those boards for parts Randy Dupree will have the parts, I had  the Primus  2 boiler system in my Eagle for 20 years and never had any problem except for 1 pump, I think I still have a control panel ,valves and ignitors for those I bought and never used. Primus was a good system they used a lot of propane but were quite .My MCI used the Oasis it was pretty much trouble free and parts were cheap because it used a low pressure Pro/Heat boiler system, the Aqua /Hot in my Country Coach used the Webasto high pressure system and the price of parts would make you faint and it was one of the latest model that used $35.00 a gal antifreeze 

Re: Propane to Diesel Hydronic Conversion Primus to Aquahot, Webasto or Other

Posted: Mon May 27, 2024 6:57 pm
by Seann
For what it's worth, the Primus system works very well. Have used it for 3 years, keeps the interior nice and toasty (lots of variables, YMMV).

Unless there is an issue there may be no need to replace it. The pump did have to be replaced, bought from Dupree last year, and verified that they do have both the control panels and interface boards (located at the heater) in stock.

Image

 

Re: Propane to Diesel Hydronic Conversion Primus to Aquahot, Webasto or Other

Posted: Tue May 28, 2024 7:46 am
by rusty
Good news for the wallet and time to change one out. Safe travels
Wayne

Re: Propane to Diesel Hydronic Conversion Primus to Aquahot, Webasto or Other

Posted: Mon Jun 03, 2024 2:19 pm
by Panton
Thanks fellas! Fantastic information. I am running down several scenarios to update the bus. Deciding how deep to go into each system and what needs to be done first as a basis for the rest of the upgrades, and what can be done later over time.  I am considering eliminating propane as a fuel source all together in favor of diesel and electric for everything. As always every thing you add and subtract moves something else around. I am still drawing it out.  All your input is very valuable. Thanks for sharing it.  

Based on what you guys are saying I think I might spend a little time on the Primus just to see if I can get it working before I I just yank it in favor of the diesel option. Thanks again!