Low Point Drain Valve Leak

[RonMcMusic]

Last night I noticed water under the street-side wheels of our 2013 Serenity 27'. This morning I saw that there was a steady drip from the rear low-point drain valve, the hot water line. I opened and closed the valve several times but the drip continued. We are in a campground near Spearfish SD, close to the Wyoming border, and are heading west on our way to Oregon. We are still somewhat newbies so I need to know:
Is this a common problem and is there an easy fix?
Do I need to get this repaired immediately?
Do I need an Airstream dealer or would any RV dealer be able to fix it?

Thanks in advance for your suggestions!
Ron

[rmkrum]

Its possible that the valve has gone bad, but another possibility is that the Water Heater has lost its air bubble that acts as an expansion space when the water heats up.

You could shut off the water pressure at the campground spigot (I assume you are hooked up) and shut off the water heater. Let the water heater cool down for safety, then unscrew the drain plug on the cooled off water heater and let all the water flow out. Replace the plug, then turn the water back on. let the excess air out of the system by opening your water faucets, especially the hot water ones.

Before you turn on the water heater, see if you still have a leak from that valve. If not, the valve may be OK. If it still leaks with the water heater turned off, and the system pressurized, the valve is most likely bad and needs to be replaced. There are mobile RV repair folks that can handle this kind of repair if you do not have the tools and experience to do it yourself..

If there is no leak with just water pressure on the trailer, Make sure the water heater is full of water again, then turn it back on. If the leak stays gone once the water is hot again, it was the missing air bubble in the heater.

Another weird possibility is the regulator right behind the water inlet to the trailer--sometimes they fail. A quick fix would be to install a pressure regulator at the campground spigot to limit your pressure to about 40-60 pounds max. That also protects your hose to the trailer. If possible, use an adjustable regulator with a pressure gauge so you know what is going on...

[RonMcMusic]

Thanks so much for your quick and thorough response! I will try this immediately.
Ron

[rmkrum]

Do let us know the outcome

[GMFL]

You can also use a food safe silicon grease on these valves and it will help them seal better. I have a small tube that came with my Yeti bag cooler to lube the zipper. Works great to keep flesh water tank and low point drains in good shape

[HiJoeSilver]

The bubble could help stop the leak.

Plus it depends on the exact valve they used. I had to cycle mine about 20x with a good flush each time to get it to reseat without dripping anymore.
Any rv dealer or even plumber should be able to repair this type of thing. If I was in spearfish I'd come help ya but I'm not. Access to the valve is usually the hardest part. If it's just a small drip I wouldn't sweat it.

[OTRA15]

Ditto to the good advice so far, adding the footnote that you only have to drain about a gallon of water out of the water heater, to re-establish the head of expansion air at the top of the tank.

When you get everything working again, you might want to check at the top of the water heater, to make sure that your pressure relief valve has not been leaking air. If it has, you will see mineral deposits at the shaft with the flip-up handle [to manually let air out]. Do not operate this valve with the water pressure on, as you will lose your head of expansion air.

If there are mineral deposits, you may need a new valve, but that is a separate discussion. Let us know if this is the case.

Good luck,

Peter

PS -- Your owner's manual, and the mfg. booklet about the water heater, will give details about the pressure-relief valve. You should read all this material before you do anything IMO. The AS manuals are not perfect, but are always a good place to start when you have any problem.

PS2 -- If you do have mineral deposits on a 2013 unit, it might suggest that you have been using hard water, which could also be the reason that your low point drain valve is not closing right. Do you see mineral deposits in other places like the kitchen faucet spout's aerator/filter? Or on the shower spray head? Etc. If you know that your water is hard, there are probably some remedial and proactive steps you should take, but that is also a separate discussion for later.

[RonMcMusic]

I believe OTRA15's comment about hard water is right on target. We just spent a month at the Minnesota Airstream Park in Clear Lake MN. The water there is hard. We noticed mineral deposits on all surfaces which came in contact with the water.
HiJoeSilver mentioned that he needed to cycle the valve 20X to get it to seat. I will try that. Is there something I could put in the water which would remediate the hard water deposits on the valve and not be a problem in the water heater or other parts of the system. The water in my fresh water tank came from the Airstream park. I will drain it and fill with some water from here in Spearfish SD.

Yesterday I did drain the water heater then refilled the system without switching the heater on. The drip at the hot water low point valve continued.

Thanks for your replies!
Ron

[rmkrum]

Bypass your water heater like you do to winterize. Then try draining your fresh water tank, put a couple gallons of water 50-50 mixed with a couple gallons cheap distilled vinegar in gallon bottles into the fresh water tank so your pump has something to work with. Use the pump to pressurize the system, then cycle the low point drain a few times to get the solution into it. Let us sit for a while, then cycle it again to flush out dissolved minerals. Continue flushing and letting it sit. Once you run out of the vinegar solution, flush and drain your fresh tank and piping to get rid of any remaining vinegar flavor. Refill to desired level.

Theoretically the vinegar will dissolve any hard water deposits in the lines and valves.

Might have to remove and flush all faucet aerators to get particles out as well. This concentration of vinegar should be mild enough to clean hard water deposits out of the system without causing more issues.

[RonMcMusic]

Thanks so much! Sounds like a good plan.
Ron

[OTRA15]

Thanks for the reply Ron. Be sure to follow rmkrum's advice carefully, as he has put specific points in without emphasizing their importance IMO. I will add some emphasis [IMO]:

Originally Posted by rmkrum

Bypass your water heater like you do to winterize. Then try draining your fresh water tank, put a couple gallons of water 50-50 mixed with a couple gallons cheap distilled vinegar in gallon bottles into the fresh water tank so your pump has something to work with. Use the pump to pressurize the system, then cycle the low point drain a few times to get the solution into it. Let us sit for a while, then cycle it again to flush out dissolved minerals. Continue flushing and letting it sit. Once you run out of the vinegar solution, flush and drain your fresh tank and piping to get rid of any remaining vinegar flavor. Refill to desired level.

Theoretically the vinegar will dissolve any hard water deposits in the lines and valves.

Might have to remove and flush all faucet aerators to get particles out as well. This concentration of vinegar should be mild enough to clean hard water deposits out of the system without causing more issues.

Personally I would let the vinegar solution sit for a couple of hours, but this is just my own seat-of-the-pants guesstimate. Be sure to run this solution out of all outlets, both hot and cold, including the outdoor shower, and all low point drains. If you start with 4 gallons total of vinegar solution, you have to be careful to apportion it so you have enough for the entire system. If you start with 4 gallons of water, and 4 vinegar, that would be easier IMO.

Flushing the system with water will be much easier if you can use city water, and open the gray tank dump valve to run all effluent into the sewer system. You should also open the low point drains to flush, but you can throttle back the water flow by turning down the hose bib real low -- just enough flow to get the vinegar out of the low point drains, which are "dead ends" in most systems.

Here are the search results for "hard water vinegar" which might round out this discussion FYI:

https://www.google.com/search?q=hard...com&gws_rd=ssl

Good luck!

Peter

[RonMcMusic]

Zzzz

[HiJoeSilver]

This thread below got into the WH flush. Instead of filling the FW tank I'd add vinegar to the WH by funnel into the TPR valve. You can then then flush some to the lp drain. Let sit overnight or 12 hours. You'll get the WH maintenance done.

http://www.airforums.com/forums/f445...sh-165089.html

[RonMcMusic]

During the process of flushing the system with the vinegar solution I noticed that there was a fine mist of water spraying from the low point valve assembly. I had not seen it previously. I can't tell for sure but it appears to be coming from where the assembly connects to the pan area. The drips are now more frequent, more than one drop per second. I therefore assume it needs to be replaced. We were planning to leave tomorrow(Sunday) heading for Portland OR. We will postpone and on Monday I will call local RV dealers to see if they can work on it. I would like to head west asap to avoid inclement weather in the higher elevations. Another possibility is to try to find an RV dealer along I-90 in Wyoming with sufficient lead time to make an appointment. As a newbie this is my first time taking a trailer in for service.
Thoughts?
Thanks
Ron