Drain water heater

[Grumpy Grampa]

Just one question. When draining the water heater on a 37.1 2017 Miramar how you keep water from running on to the side of the unit?

[Beau388]

Originally Posted by smithgarnat@aol.com

Just one question. When draining the water heater on a 37.1 2017 Miramar how you keep water from running on to the side of the unit?

I don't. If you have soft water or a water softener, it doesn't streak.

[Pete'sMH]

Originally Posted by smithgarnat@aol.com

Just one question. When draining the water heater on a 37.1 2017 Miramar how you keep water from running on to the side of the unit?

Don’t know why you would worry about your RV getting wet but some folks replace the plug with a short hose and valve to make it easier to drain and that would work for your purposes as well. If you open the lever on the pressure relief valve it will let air in and much of the water well flow with enough force that it will jump over the side cleanly. In any case you would want to let the water cool before emptying. I often run hot water into my gray tank with the heater off to help flush out the tank and to cool off the water heater before draining.

[Campnjoe]

Just use your low point drains and don't crack open your water heater. I open both drains and then open both sides on a faucet. Suction will drain the water heater. Takes a lot longer to drain this way but it works all the same.

[Pete'sMH]

Originally Posted by Campnjoe

Just use your low point drains and don't crack open your water heater. I open both drains and then open both sides on a faucet. Suction will drain the water heater. Takes a lot longer to drain this way but it works all the same.

THAT is a really clever idea! I hadn’t thought of it and it’ll leave a little more water in the tank than using the drain valve would but certainly it’ll do the trick and it’s a lot easier than fussing with that drain plug!

[Avi8rMD]

Originally Posted by Pete'sMH

Don’t know why you would worry about your RV getting wet but some folks replace the plug with a short hose and valve to make it easier to drain and that would work for your purposes as well. If you open the lever on the pressure relief valve it will let air in and much of the water well flow with enough force that it will jump over the side cleanly. In any case you would want to let the water cool before emptying. I often run hot water into my gray tank with the heater off to help flush out the tank and to cool off the water heater before draining.

I saw a photo of this “hose”mod on a post a couple of months ago and can not find it now. Any idea how to put that together?

[Avi8rMD]

Originally Posted by Avi8rMD

I saw a photo of this “hose”mod on a post a couple of months ago and can not find it now. Any idea how to put that together?

Just found a suggestion…

Originally Posted by pstandiford

I took mine out and put in a 1/2 x 3/8 reducer. Next a 9” braided faucet hose with a 3/8” ball valve on the end. Now when I want to drain it I swing the hose out and open the valve. Doesn’t run all over the inside of the water heater that way.

[Travelin' Texans]

Originally Posted by Campnjoe

Just use your low point drains and don't crack open your water heater. I open both drains and then open both sides on a faucet. Suction will drain the water heater. Takes a lot longer to drain this way but it works all the same.

I don't know what water heater you have, but if it's an Atwood or Suburban there's no way you'll drain the water heater by opening the low point drains. Those heaters are approximately 12"+ diameter, cold water enters in the bottom, hot exits the top, there IS NOT a line from the hot side to the bottom of the tank so no way to siphon or suction. The ONLY way you'll completely drain it is to remove the plastic drain plug on an Atwood or the anode rod on a Suburban (good time to replace the anode rod if needed) then open the pressure relief valve, be sure heater is off & has cooled. If adding a valve to the Atwood brand be sure all fittings are brass or plastic to prevent galvanic corrosion due to mixing dissimilar metals.

[Pete'sMH]

Originally Posted by Travelin' Texans

I don't know what water heater you have, but if it's an Atwood or Suburban there's no way you'll drain the water heater by opening the low point drains. Those heaters are approximately 12"+ diameter, cold water enters in the bottom, hot exits the top, there IS NOT a line from the hot side to the bottom of the tank so no way to siphon or suction. The ONLY way you'll completely drain it is to remove the plastic drain plug on an Atwood or the anode rod on a Suburban (good time to replace the anode rod if needed) then open the pressure relief valve, be sure heater is off & has cooled. If adding a valve to the Atwood brand be sure all fittings are brass or plastic to prevent galvanic corrosion due to mixing dissimilar metals.

That is not true. As you yourself point out the cold water line is at the bottom of the tank. If you open the cold water low point drain and any faucet hot line the tank will drain through the cold line while air enters the top of the tank through the hot line. On mine the cold water inlet is lower in the tank than the drain plug so it actually drains a bit more water this way. It works just fine and is way easier than doing it from the outside. Try it and then you can prove it to yourself by removing the drain plug to verify that no water will come out.

[Travelin' Texans]

Originally Posted by Pete'sMH

That is not true. As you yourself point out the cold water line is at the bottom of the tank. If you open the cold water low point drain and any faucet hot line the tank will drain through the cold line while air enters the top of the tank through the hot line. On mine the cold water inlet is lower in the tank than the drain plug so it actually drains a bit more water this way. It works just fine and is way easier than doing it from the outside. Try it and then you can prove it to yourself by removing the drain plug to verify that no water will come out.

To be honest I haven't had to drain to winterize in about 15 years, anode replacements only, spent winters somewhere/anywhere there was NO cold or snow. The last ones I had to winterize had a check valve "in" on the cold line & one "out" on the hot, could not drain with the low point drains without removing the check valves.

[Pete'sMH]

I had a water heater once that had such check valves and indeed this wouldn’t work in that case. When I had that my bypass system was a single valve (the check valves taking the place of the other two valves in the more typical three valve system). So I’ll agree that this is a good plan if you have a three valve bypass. In any case, for most folks it’s worth a try. If it works it’s a whole lot easier!

[wrapped]

They do have a check valve so hot water can't migrate into cold water system, so you can't drain tank with low point drain.

[Avi8rMD]

I appreciate all of the advice. Coach is new to me and I will look into all suggestions.

[blw2]

Originally Posted by Campnjoe

Just use your low point drains and don't crack open your water heater. I open both drains and then open both sides on a faucet. Suction will drain the water heater. Takes a lot longer to drain this way but it works all the same.

a variation on this idea....
with the low point drains open...or in the case of my rig anyway the outdoor shower is lower than the water heater, so just open the hot side of that shower. The water won't drain, or as you suggest will take a very long time....but if you simply crack open the TPRV valve on the heater it vents air in at the top and the water will drain right out.
and i figure that it does drain just as well as pulling the plug (which is a lot more work) because the hot outlet pipe is at the same level as the plug is.....so there's still likely a little water in the bottom, but not much....

[Grumpy Grampa]

Thanks for all the input.

[chunker21]

Removing the actual W/H drain plug and/or anode will let you get stuff/debris out of the tank. An earlier post referred to a flushing hose but use caution with them. Camco makes one and several reviews complained the end of the hose that you stick in the W/H drain, blew off and went into the W/H itself. May be difficult to retrieve. Annually I would drain and flush out the W/H as part of my annual maintenance and cleaning. Generally lots of deposits would come out. Of course it is has an anode, a good time to inspect and or replace as necessary.

[To Camp]

If you can't drain via the low point drain, make a large funnel by cutting the bottom out of a plastic jug. Windshield washer fluid or winterizing fluid jugs would work best.

A piece of sheet metal or aluminum flashing would work also.

[txc2936@yahoo.com]

Last night in SC, the temp dropped to 28 Deg F. I turned on the tank heaters and only the Gray water tank lower surface is warm to touch. I check CB and they are intact at the panel. Any suggestion on how to trouble shoot. I know they have a thermostat in them. If i peel a little wire back the heater pad, should i be reading 12 Vdc there.