3 Gallon Hot Water Tank Questions

[Ruck_and_Roll]

I have a '08 FWC Hawk with a 20 gal and 3 gal hot water tank w/water heater. I've had the camper about 4 months now and I haven't really bothered operating the hot water heater at all.

I am in the process of winterizing.

This probably sounds like a very stupid question but how exactly does the 3 gallon hot water tank fill? I've consulted the manual and see nothing about how the 3 gallon tank fills. Does it divert water from the main when the hot water is on? Or does it just fill up concurrently with the same entry cap as the 20 gal?

Stumped.

-Luke

 

[longhorn1]

Not stupid at all. Iwould call FWC. Our 2014 Grandby has the 6 gallon hot water tank filled by turning on the hot water knob. We can also drain it back into the water tank. No matter what, there will be water in the water tank, hot water tank, pump, and lines. I run Pink RV Anti-freeze through all the lines. I start with 3 gallons and turn the pump and run through each line, so some will remain in the tanks, pump and lines. You will be good for the winter. Do call FWC and they will help. jd

I have a '08 FWC Hawk with a 20 gal and 3 gal hot water tank w/water heater. I've had the camper about 4 months now and I haven't really bothered operating the hot water heater at all.

I am in the process of winterizing.

This probably sounds like a very stupid question but how exactly does the 3 gallon hot water tank fill? I've consulted the manual and see nothing about how the 3 gallon tank fills. Does it divert water from the main when the hot water is on? Or does it just fill up concurrently with the same entry cap as the 20 gal?

Stumped.

-Luke

 

[Wandering Sagebrush]

Luke, to fill, you need to either have the pump on and open the hot water faucet, or city water connected and open the faucet. It will spit and sputter, then run solid when filled. I suspect you have a bypass that if on, you’ll need to turn off to fill the tank.

Check FWC’s website, I believe they have model/year manual that you can download.

 

[Old Crow]

You might take a look at esimmers' excellent 'Inside Cabinet Take Apart' thread for comparison to your Hawk. His is an 09 Hawk and I'm guessing your 08 is the same or very similar.

I especially like his water system schematic in that post....



Note the water direction arrows and the left valve.

That valve is what controls whether water does or does not flow into the 'in' side of the water heater.

Also-- Note that the clear hose is a drain hose. However, during winterization you still have to drain the hot-water tank separately, i.e., by removing the plug. (You'd want to do that anyway to inspect the anode rod and flush the tank. Note that the manual says not to leave water (and especially antifreeze) in the tank long-term as it will deteriorate the rod.

Note for others-- FWC installed Suburban water heaters for a few years and those have an anode rod. Also, the coiled drain hose design was changed to an exterior drain for the 2010 models.



.

 

[esimmers]

Old Crow, you are too kind. My grandson can draw a better water system schematic but I guess my drawing does the job.

Ruck_and_Roll is winterizing and wants to know how the hot water tank fills. I guess my schematic shows that but leaves unsaid some details showing how to winterize.

Yes, the first step of winterizing is to drain the hot water tank by removing the plug behind the outside access panel - relieve the pressure in the whole system by turning off the pump and opening a faucet. Otherwise you'll get a shower when you remove the plug. My plug takes a 15/16 socket wrench but yours may vary. Suburban water heaters have a sacrificial anode attached to the plug. Atwood heaters just have a plastic plug with no anode; their tank is aluminum, not steel.

You may wonder what the two valves in the drawing do. The one closest to the pump closes off the hot water system completely. The other valve is for the drain hose at the lowest place in the system to drain as much water as possible out of both the hot and cold systems. In newer campers, that drain hose either runs to the outside or back down into the main water tank. In my 2009 Hawk, I have to use a bucket. Open faucets when draining to make the job faster.

FWC has good guides in their manuals for how to winterize, both with and without using the Pink Stuff, depending on how meticulous you are. But basically, drain the main water tank and the hot water tank, open all the faucets, run the pump until only air runs out, open the drain valve, and you're good to go. Don't forget the outside shower; plug in the hose so air can flow in to drain the faucets and supply lines. You may want to put a bit of pink stuff in the sink drain, but there's no need to worry about the tanks if they're drained.

 

[Ruck_and_Roll]

Thanks for the help folks.

FWC was helpful. Sounds like there is an internal valve that is operated by the hot water faucet or can be adjusted through the cabinetry and water enters the hot water tank via THE PUMP. (like in the above schematics).

On Sunday, prior to my post, I was finally able to get the totally rusted external drain plug open (with the help of some PB blaster) and the appropriate socket. What a disaster inside. It appears as if it was definitely improperly winterized by the previous owner. The anode rod was severely corroded and there was A LOT of crud floating about! I think the previous owner had just left antifreeze in there for who knows how long.

Will start with a new anode rod and fire up that bad boy in the spring and will hopefully have some hot water.

Enjoying the adventures of buying used

Best,

Luke

You might take a look at esimmers' excellent 'Inside Cabinet Take Apart' thread for comparison to your Hawk. His is an 09 Hawk and I'm guessing your 08 is the same or very similar.

I especially like his water system schematic in that post....

esimmersWaterSystemDiagram.jpg

Note the water direction arrows and the left valve.

That valve is what controls whether water does or does not flow into the 'in' side of the water heater.

Also-- Note that the clear hose is a drain hose. However, during winterization you still have to drain the hot-water tank separately, i.e., by removing the plug. (You'd want to do that anyway to inspect the anode rod and flush the tank. Note that the manual says not to leave water (and especially antifreeze) in the tank long-term as it will deteriorate the rod.

Note for others-- FWC installed Suburban water heaters for a few years and those have an anode rod. Also, the coiled drain hose design was changed to an exterior drain for the 2010 models.



.

 

[Wandering Sagebrush]

Luke, if you haven’t flushed the HW tank, now is a great time. Just hook city water, leave anode and/or drain plug out and let it run for a bit.