Community Forums

Vtxbiker · 12-21-2015, 07:25 PM

My system fluid level is fluctuating and was wondering if this is normal. There is a cold level and hot level line and I have added fluid to the cold level line a few times during the past 2 years. I would estimate maybe 3 quarts total in the last 2 years.I checked it today as I was winterizing the coach and found it low. I have the coach parked on a concrete pad and see no evidence of a leak and none inside of the coach.
I would be interested in some others share how often they add fluid and how much.

Thanks

kraig · 12-22-2015, 12:12 AM

It should not be normal to lose fluid. The system isn't that much different then the radiator in your car. I had a small leak on mine several years ago. It turned out to be a hairline cracked brass fitting on a inlet line on the back of the hydro hot. The line was probably over tighten when the coach was made. As far as finding it was not easy, since the back of the hydro hot is not accessible. A small leak on the back of the hydro hot leak could leak be on the OSB underlayment. There should be a small weep through the OSB. I had to be measure and be very careful, when I cut an rectangular access hole through the OSB. Then I could tell the fitting was wet, but not see the crack. I ended up pulling out the entire hydro hot, which was no easy task. Once I got it out and put on a bench to pressure test. I applied very low air pressure to find my cracked fitting.

As far as your problem, you could cut an access hole in the OSB and see if you could see any leaks. I just screwed a little piece of aluminum to cover the hole back up. The other thing you could do is not worry about it, if it does not get any worse than that.

The other thing you could do is replace the radiator pressure cap. It is just a automotive pressure cap. Also make sure the vinyl hose and plastic tank are ok.

Melorene · 12-24-2015, 07:59 AM

If you are going to be at Desert Rat, have Orman look at it for you. he is a certified AQH tech and will be there

Birddog Pilot · 12-24-2015, 03:48 PM

I had the same problem for years and had checked all the lines and heat exchangers many times finding no leaks. The "experts" at the big shops had always done the yearly service and they too could not find any leaks. The first time I did my own annual maintenance it was easy to see that the plastic drain had been leaking for some time. Apparently the leak was so slow that it basically dried itself during normal operation and never did reach the concrete floor in my airplane hangar. I replaced the drain with brass and steel fittings that included a shutoff valve and I no longer have a loss of fluid.

tom chelbana · 12-26-2015, 01:25 PM

We have had to add about a pint every 1 1/2 to 2 years. Can pressure check if like our unit that uses a radiator cap on top of the unit. Should hold 10 psi for 15 min. At this point I would say after checking as you have I don't think I would say you have a problem till the usage goes up.

Vtxbiker · 12-26-2015, 08:15 PM

Thanks for the replies, I have replaced the cap on the tank and checked all lines and drains for leaks. The unit is functionally great so I guess I will keep a close eye on the level and keep on trucking. I may check the system pressure as suggested to see if it holds 10 to 15 psi. If I find anything I will post it.

Thanks again