Oasis Hydronic Heating System Zone problems

[ubfj]

I have a 2009 Newmar Dutch Star purchased in 2010, new. The Heating systems have been working great until this last trip. First when it got cold, in the low 30s, the heat pumps started going into some kind of a shutdown cycle where the heat pump would run but no heat would come out of the vents for up to 10 minutes. They made loud noises during this cycle, then heat would come out until the next cycle, then it would do it again. This was mainly the bedroom AC, but the front AC would do the same once in a while. Then when the temp got down into the 20s I decided to use the Oasis Hydronic Heating System furnace. So here is the problem: The bedroom and baths heat vents put out heat just fine. The front living areas only put out cold air. The fan came on at the correct temp setting, but the coolant feed pipes for the front system was cold. I checked the system lights for the heater and the distribution panel and they were on correct. I checked the fuses one by one on both the heater and the distribution panel and they were all good.
Anyone got a quick fix to get the distribution panel to send heated coolant to the front of this coach?

[ubfj]

Ok just got an email from the factory, can you believe that, on a Sunday. After reading it I decided to try and fix it and I did
Here is the email I received from the factory rep: It was a stuck valve and after I did what he suggested it worked...

Is this a single loop or double loop system? If you have a single loop and some of your fans are blowing out hot air and some are blowing out cold air, then the problem is a lack of flow in the system. This is most likely due to an air lock in the system. If this is the case, then the coolant system needs to be purged. There are purging instructions in the service manual for the Oasis heater which can be found on our website (www.itrheat.com).
If you have a dual loop system and the rear loop is the one that is blowing cold air, then either there is an air lock in that loop, or the pump for that loop is not running. It is also possible that there is a check valve in the distribution module that is stuck. To test if the check valve is stuck, open the front of the distribution module (the module with all of the hoses connected to the top and side - not the Oasis heating module) and use the back of a screw driver to tap on the check valve that is just above the pumps mounted on the right hand side of the distribution module. After you tap on the check valves, see if you get heat distributed to the front fans.
Also, make sure that the fuse for one of the pumps has not tripped. You will see a RED light on the zone board next to the pump if the fuse has tripped. Note that there must be a call for heat for that pump to run before any lights are displayed. If the fuse for the pump has tripped, that that would also explain why you're not getting any heat coming out of the fans. Note that this fuse should be 10 amps.

[Iron Man]

If you do not exercise the heat periodically the check valves will stick. I think I would check that before trying to purge out the air in the system.

[ottffss]

Below 40 just always use "furnace" not "heat pump" as I have found Newmar's crossover system always a little clunky...

Check valve is the #1, #2, #3 prospect. Shake-rattle-and-roll it and see if that makes it go. You can do this with the zone hot and running (the valve will be hot) and then you should feel the hot flowing to the formerly cold side of it if you are able to break it open.

If the fans are on so "should" the pump (same circuit controller) so that points to coolant supply (or lack thereof).
These are self priming pumps... You of course checked the coolant level in the tank in the engine compartment?
If that is fine open the radiator cap on the Oasis (COLD!!!! it takes hours to cool off) and make sure it is at the top. Cover the area with rags.


The "coolant" in the Oasis is a boiler antifreeze (and use only that). Camco has it and I've seen it (another brand) at some Home Depots too in the plumbing area.