Hot water tank dripping

Maple_Geek

Hello, I'm using my hot water tank for the first time. I am connected at a relative's house on city water. When the system pressurizes, water always leaks from the hot water drain tube.
My TAB comes equipped with an inline water regulator but to be extra cautious I'm also using a variable regulator so it's hard to say what pressure comes into the trailer but it's not much based on what comes out of the cold water tap...20 PSI maybe?
When I'm not using any water and the system is pressurized, I see close to 60 PSI on the variable regulator dial.
I've wiggled the yellow drain valve and I find it quite loose. When it's standing up, it's draining but when set on either side it looks like it's closed....but it drips when the tank is pressurized.
If I open the hot water tap it stops dripping. Same if I bypass the hot water tank.

Short of having a faulty valve, I'm not sure what else it could be. Can using 2 pressure regulators cause weird behaviours like this?

Thanks in advance for your insights.

pthomas745

So: the water is coming from the Yellow valve?  The valves have been known to fail, or to get some sort of debris in the valve that prevents it from sealing.  Can you press it down until you feel it "click" into place?

60 psi is higher than the trailer really can handle.  The trailer "normally" should be down to 40-45psi (described in this thread).

https://tab-rv.vanillacommunity.com/discussion/12294/camper-water-pressure-plumbing-heating

Not sure where your variable regulator is mounted, but you might want to get it down to the levels described above and see how the yellow valve reacts.

There has been great interest in the groups about the "installed" pressure regulators, as in...do they work, etc.  NuCamp doesn't seem to be installing them any more, but it is hard to tell why.  So, your experiences with it will be interesting to hear.

Maple_Geek

Thanks @pthomas745. The water is dripping from under the camper...from the hot water tank drain that is controlled by that yellow valve.

My variable regulator is right at the house tap. Then I have 35 feet of hose that enters the TAB in the Nautilus city water inlet. They way it's currently setup I don't think I have 60 PSI of pressure based on what comes out of the trailer tap when I open them. It's very weak. I'm guessing about 20 PSI but when I shut everything off, the variable regulator is showing me 60 or 65 PSI....I don't understand that part.

I will try to push on the yellow valve

pthomas745

So, the variable regulator is showing water coming into the regulator is 60 psi?  That would be normal.  Can you tell what is going out to the camper? 

Maple_Geek

The regulator can be adjusted so I don't believe I'm adjusting the water pressure coming out of the house. I believe I'm adjusting the water pressure going out to the hose and into the camper.

The variable regulator is showing 60-65 when everything is pressurized at my current setting. Then it enters the Nautilus and sees the inline fixed regulator. What comes out of my tap is barely adequate in my opinion. 20 PSI maybe.

But the water flow varies. When it's pressurized and I open the tap it comes out stronger (i.e. normal house tap pressure) but it slowly dwindles down to what I think is about 20 PSI.

If I adjust the regulator to a point where the hot water tank drain stops dripping, I get barely anything coming out of the tap. So I don't think I'm over-pressurizing the system.

Denny16

One way to know,what the pressure coming from the hose pipe to the TaB, is to buy a water pressure gauge with a hose pipe connector that attaches to to the hose, and measure the actual pressure.  Set this to 45psi with your regulator, and Bob’s your uncle...  

As for the pressure coming from the galley or washroom tap, they have an additional pressure/flow restriction screen to reduce water consumption.
 Cheers 

kottum

A source of pressure buildup and subsequent small leaks is the expansion of the cold water as it enters the plumbing system, and then warms up and expands in the closed system.  I have installed a water pressure accumulator in previous camper trailers to successfully stop these increased water pressure leaks.

https://www.amazon.com/dp/B000N9VF6Q?psc=1&ref=ppx_yo2ov_dt_b_product_details

Doug

Maple_Geek

Thanks @kottum but this happens with the water heater turned off so I don't think this is the issue I'm seeing.

Sharon_is_SAM

Just for kicks, can you place the pressure regulator after the hose and see if that makes a difference?

ScottG

That yellow flapper valve is designed to automatically relieve excess pressure in the plumbing system to avoid potential damage to the Alde and other components. From what you describe, it sounds like a) your water pressure is too high; and b) the valve is doing exactly what it is supposed to do.

Focusing on the HW tank is a red herring. While the yellow valve does also serve as a drain for the HW tank, it is not otherwise related.  

Maple_Geek

@ScottG thank you for this. So is getting 20 PSI or less of water pressure at the sink tap in the camper is all I should expect? 

To make sure it no longer drips, I have to turn it down to a trickle. Seems excessive to me.

Mickerly

If I saw the photos correctly of the back side of the 2022 T@B Nautilus system, there really isn't a "regulator". It's really a restriction. Plumbing pressure can be as high as 120 to 160psi. The restriction reduces that to 45ish psi. You are placing a regulator before the restriction to bring the pressure to 60?psi. From there the restriction device in the trailer will reduce the pressure more. So, your guess of 20psi sounds about right. If you add the pressure drop across the filter, 20psi may be a high guess. Again, this is a guess based on two photographs and your description.

If you're curious, find a friend that has one of the barrel shaped 'regulators' (typically blue plastic). Pull the hose washer out of the one end. The restriction piece will fall out for cleaning. It's not a regulator, it's just a plastic tube with a restriction in the middle. The brass ones are typically glued in and are difficult to clean. Yes, the package says "regulator" but it isn't; no moving parts.

An adjustable regulator with a bell shape part and a screw on top for adjustments is a regulator. If this is what you have, set the pressure to 40 to 45 psi as Denny16  recommended above. If you have a barrel with a gage, you have a restriction with a gage. Using either in addition to the restrictor in the trailer will significantly reduce the pressure available.

The yellow valve should be the hot water overflow. Opening the valve for a moment as water flows through then closing the valve will clear any bit of stuff stuck in the valve. Not unusual for bits to get stuck in valves during manufacturing. If that doesn't fix it, the valve may not be sealing, as in bad valve.

As mentioned above, the water heating will expand and cause some leakage periodically. Also, having water system pressurized for long periods and loosing the airspace in the top of the hot water heater could cause this too. Follow the owners manual directions for establishing the airspace.

Entirely a technique, We depressurize and drain after each trip. This prevents stagnant water and associated poor water taste. Also, it re-establishes the airspace in the hot water tank on every trip. 

ScottG

Maple_Geek said:

@ScottG thank you for this. So is getting 20 PSI or less of water pressure at the sink tap in the camper is all I should expect? 

To make sure it no longer drips, I have to turn it down to a trickle. Seems excessive to me.

As @pthomas745 mentioned, it is possible for the yellow valve to be faulty and drip when it shouldn't--it's hard to say whether that is the case or if your system really is over pressurized.

FWIW, I also notice that my HW pressure drops off noticeably shortly after opening the tap. I've never actually measured the pressure, though, so I can't say if it is as low as 20psi. It's certainly not very forceful, but it's good enough for camping IMHO.  :-)