Resolved Oasis heater module fault red LED lit, No burner heat??

[Rustymayes]

This weekend I was using the furnace to heat the coach while out Glamping on the Russian river. Over night temps already getting into low 30s!
I had the burner on and both AC elements and realized that the coach stopped heating up. I had the floor heat on as well which kept the core temp up a bit and I realized also that when I ran the aqua miser for the shower that the red light was not lighting. I shut off the furnace heat and the water did heat on the electric but not enough to warm the coach and have shower hot water.
I noticed the heater module led lit so checked the Oasis front panel and the module panel on the bay wall and saw no red LEDs. There were several green ones not lit. I hit the reset button on the unit and that cleared the fault light but it came back as soon as I selected the burner again. Any ideas on what to look for. I am suspecting the igniter? that green light was blinking green after reset with burner selected. I will cycle the salesman switch just for grins not that I am back home and before I power up the coach on my 50 AMP supply.
Thanks for any insight.

 

[Neal]

Do you have a service kit? When is the last time you had your unit serviced such as routine parts replaced?

I keep this kit on board, it's the most complete of them:

Amazon product ASIN B01N75RKTE
Download and refer to this guide but if all else fails call ITR tomorrow.

ITR Oasis Service & Troubleshooting Manual

ITR Oasis Service & Troubleshooting Manual

rvforums.com

 

[SteveMA]

Check your boiler fluid tank to be sure you are within the ‘range’ for cold level. If low or empty you may have induced air in the recirculating pipes and you will not get proper heat from electric or burner. What year and have you performed annual service on the oasis boiler - burner side (full disclosure - I carry parts but change everything -2 year cycle)

I had a somewhat similar problem and unplugged the connectors from the oasis controller while the salesman switch was off (for a few minutes).

Having had our coach in 16-31degree temps the electric has been ok for almost everything except long showers. So my first guess is fluid level as electric and fuel boiler are both impacted by the water circulation

Also call ITR like Neal said.

Final note I was intrigued where my boiler fluid was going. Seems many of the units were installed with the hose fittings on the boiler unit not correctly tightened and you get a tiny bit of leakage of boiler fluid around the top of the boiler unit. Several threads about this. Once I confirmed and tightened them up (double wrenches!!) my fluid loss went away.

 

[Rustymayes]

2022 4081. I bought it just one year ago and have 125 hours on the heater. I just checked the fluid level and it is right in the middle of the range. It is hot since I just drove 85 miles and the electric is working. I have checked it stone cold and it has always been at the cold line.
@Neal, I will look into the TS guide you linked. Your help is always appreciated. DO you all ever sleep? You guys should put on customer service training seminars for all the vendors!!!!!

 

[MemoriesByTheMile]

Do you hear the hear the burner trying to light but not staying lit? If so, the nozzle may need to be cleaned or the o-ring on the nozzle may need to be replaced. Or the flame sensor could have gone bad.
If the burner is not trying to light, my experience has been that the igniter may not be functioning.
Like Neal suggested, call ITR tomorrow and carry a full set of maintenance parts. Replacing/cleaning a nozzle or replacing an igniter or sensor is pretty fast, once you have the parts and have done the annual maintenance yourself one time.

 

[Neal]

Sleep is a waste of time, but I think after this past week I'm going to take the night off to recharge. I wish I remembered the OASIS seminar I just attended at Newmar Hoots this past week but I'm a terrible academic now and can't remember all these trouble paths. My guess is you may need a new igniter if you have the burner on and it's not coming on. I assume too you have at least 1/4 tank of diesel?

 

[LeslieGary]

I also recommend calling ITR. They are very helpful and will walk you through troubleshooting.

You may have a bad summer loop pump. I’ve changed mine twice. Try the bypass switch on the top of the silver box next to the Oasis unit in your basement. It is a small toggle switch. Once you switch it on, you’ll hear the pumps come on (they are in the bay in the opposite side) and you’ll likely have heat and hot water after a few minutes.

Keep in mind the bypass switch keeps the “non-summer loop” pumps running, so make sure you turn it off when hot water or heat are not needed.

 

[Rich W.]

Flame sensor….It gets too hot and the “lens” deforms and it doesn’t properly sense the flame. Poor design or materials I guess, but if you pull it and find the sensing surface deformed you’ll probably have your answer.

New vs ”used” flame sensor:

 

[Rustymayes]

Thanks Rich, I will remove it to inspect.@LeslieGary, I switched on the bypass and I did hear pumps but the burner did not light off. I do have the AC side providing hot water so I am not dead in the water.

 

[Rich W.]

Thanks Rich, I will remove it to inspect.@LeslieGary, I switched on the bypass and I did hear pumps but the burner did not light off. I do have the AC side providing hot water so I am not dead in the water.

I think the symptom with the bad flame sensor was the burner lighting and then shutting off repeatedly - sort of a short cycle type of thing.