JCR-1 wrote:
Why do they use anodes then if water does not touch the metal as you suggest. If there was no contact with metal because of glass layer..no need for an anode .I am not necessarily suggesting widening the hole but rather making the 1 inch std heating element cut down to 3/4 inch and rethread to 3/4 as has the suburban tank. I am trying to find out why this cannot be done. seems not to difficult . The 450 watt seems like a long time to heat water. The 1500 watt std does it in mere minutes.Not trying to save money ..looking for better system.
The "anode" is "sacrificial" in other words the anode slowly erodes or corrodes if you will in order to prevent the dissimilar metals like copper, brass and steel which is all "touching" the water at the same time from eating away at any exposed steel (IE pipe threads).
Keep in mind that while the tank it's self is "lined" the threaded holes that go into the tank ARE NOT "lined". Those threads are a starting point for the steel to rust.
As far as putting in a 1500W element, I think you will find that a standard residential electric element most likely will be longer than a RV 450W type. You would need to measure it carefully, the element should not touch the tank on the other side
Not to mention 1500W is a LOT of power (12.5A at 120V) compared to a 450W at 120V RV heater (3.75A at 120V) to be using if you have a 30A 120V shore connection.
A 1500W element would only leave you 17.5A at 120V, your AC at min will need 13A leaving you 4.5A at 120V. Then your fridge will use 2.4A at 120V leaving you 2.1A at 120V for your converter which is 252W... Not much left.
Not being a smarty pants here, but have you ever considered changing your water usage habits a bit?
I have a 6 gallon Atwood, so far I have never ever had a cold or even cool shower and I can easily get 15 even 20 minutes of shower time.
How do I do it?
Simple, I do not run the shower at full rate.
I start by lightly turning on the hot water, once hot then turn on cold water to mix to my liking (water heater actually heats the water well above 120 degrees so you do not need a lot of hot water I am guessing I use 3-4 gallons of cold to 1 gallon of hot). I only use just enough pressure to make a spray from the spray nozzle.
If you are turning the water on hard enough to blast you against the shower wall you ARE using the water too fast.
By slowing down the water like I do you actually give the water heater time to heat the water as it enters the heater.
With a 6 gallon heater you are simply not going to get a shower like you do at a sticks and bricks but you can with a few simple changes to your usage habits make it work rather well.
By the way, I do not have an electric element in my water heater so I know it can be done..
On edit, it may be possible to reverse "bush" the hole, basically you would need to find a brass bushing threaded for 3/4 inch on one side and 1" on the other. This is provided the element would fit inside the 3/4" pipe fitting.
Although I still don't think it would be a good idea since you would need to supply your own temp limit switch which would not be included with a residential element..
