Hot Water Tank Drain

[stearn]

I know there are several post on this, but I did not see an answer to my question. I wonder if I could replace the nylon drain plug, with a galvinized nipple, attaching a reducer that I could then screw in a brass valve. The valve I'm talking about is one that when open would be about a 1/4" opening. I measured and it would be an easy fit. I had this type of valve on the sides of the motors on my boat.They were for draining the water out of the block, for winterizing. They were also found on radiator drains on older cars. Easy to use just unscrew to open then tighten to close.[trying to describe valve]

[Bob (WA0MQE)]

I did this on my previous motorhome. I just went to Home Depot and found a valve that was small enough to fit and used a nipple with have the proper threads the valve would adapt to. It was a snug fit but it worked.

[DandS]

One of the first things I did with all my RVs is to fit a shut-off valve on my hot water heater drain in place of the cheap nylon drain plugs. This is another one of those nickle/dime deals that show up on expensive vehicles. Go ahead, you will be glad for the ease of use of a valve versus the plug.

[HarveyP]

Spend a few bucks more and buy a brass nipple. A previous owner put a galvanized plug into my aluminum heater tank, and it is there permanently now. Maybe someone else can tell you if brass will do the same, but you do not want steel or galvanized. HarveyP

[Cousin Ed]

A few years ago I replaced mine with a brass peacock with a zinc sacrificer built in. I think it was about $13 at camping world.

[AFChap]

Atwood water heaters have those "cheap nylon" plugs for a reason ...I just can't recall exactly what it is at the moment ...seems it is a safety feature as I recall ...maybe for excess heat/pressure? Whatever, if you choose to defeat that safety feature by putting in a metal plug, you still need to remove the metal plug at least annually or maybe more often when you flush the water heater, both to flush it well and to keep the metal plug from welding itself in place as mentioned above. I flush mine 3 to 4 times a year, and always get lots of calcium clumps out. I just keep a couple of extra nylon plugs on hand, and replace the plug every other time I flush the WH. They work just fine for me.

[DandS]

Quote:

Originally Posted by AFChap Atwood water heaters have those "cheap nylon" plugs for a reason ...I just can't recall exactly what it is at the moment ...seems it is a safety feature as I recall ...maybe for excess heat/pressure?

Don't really think they are a safety feature, water heaters have a relief valve for excess pressure, but they may be used to prevent electrolysis and freezing up of a metal plug. I get around that problem by using a nylon adapter with a metal nipple and valve attached. That way, I still have the nylon in the metal threaded opening but have a metal valve to empty the tank.

[Jackm]

Some time ago, I spoke to an RV HVAC technician about the issue. He said the use of the nylon plug was to minimize the occurrence of small radial cracks that occurred around the hole in earlier water heaters that used metal or hard plastic plugs. The cracks, it turned out, were due to the on-going expansion of the plug when the water heater was used for any significant period of time.

Jack

[HD4Mark]

In our previous RV we had the cheap nylon plug break. A little to much cranking on it to make sure it sealed I guess. Didn't discover it until firing it up on the way to our first stop. The pressure from heating pushed the crack enough to make it fail. Swell, out on the road day one and the hot water tank is spewing out the side. A quick stop at a hardware store, a brass plug with the same thread and some pipe dope solved the problem and lasted two years. Wish I had though of putting a valve on at that point. Wouldn't have taken another 2 minutes. The new coach has petcock valve.

[rek]

In my fifth wheel. I didn't realize there was a drain plug so I always pulled out the anode to let the water drain. Sometimes the anode needed replaced. Where is the hot water tank drain located in a Motorhome.

[DandS]

The drain plug is usually located toward the bottom of the unit under and/or behind the burner assembley. Motorhomes, Fifth Wheels and Travel Trailers all use the same water heater suppliers - Atwood or Suburban - so I'm sure you have one. Look for a hex shaped white or gray threaded plug.

[DandS]

Attached is picture of my current MH set-up for hot water drain:

[Luv2go]

rek:

In suburban WH's the anode rod is the drain plug, it is located under the gas regulator in the picture in the link below, explanation pn page 7 of the second link. If this looks like the one you are pulling, you've found it.

Suburban > Service > RV Water Heaters

http://bryantrv.com/docs2/docs/operating/swinstall.pdf

Stewart

[rek]

Stewart, thanks for the info. We did have a suburban WH in our fifth wheel so you could not add a drain unless you wanted to remove the anode, which would not be a wise thing to do.