Possible damage to water heater if bypassed while on?

bshpilot wrote:

Jim-Linda wrote:


I have replaced 4-5 t/stats over the years on SUBURBAN HEATERS and have yet to see a fuse/fusible link or other device as you claim. May be getting blind, but after replacing the stat, the element came back to life.

perhaps my description was inaccurate when i called it a "fuse" but as you can see in this
picture / link - the thermostat /high limit switch has a wire (fuseable link?) that will melt & create an open circuit which will prevent current from reaching the heating element.

That wire is the physical connection between normal t-stat and high temp t-stat.
The high temp t-stat is 'resettable' when it trips open
Normal t-stat should open at 130*F and high temp t-stat should open at 180*F.
The wire can melt..but that is due to failure off both t-stats not opening OR electric element shorting and high amp low.
The t-stats should not have to be replaced unless something has completely failed.

Jim-Linda wrote:


I have replaced 4-5 t/stats over the years on SUBURBAN HEATERS and have yet to see a fuse/fusible link or other device as you claim. May be getting blind, but after replacing the stat, the element came back to life.

perhaps my description was inaccurate when i called it a "fuse" but as you can see in this
picture / link - the thermostat /high limit switch has a wire (fuseable link?) that will melt & create an open circuit which will prevent current from reaching the heating element.

bshpilot wrote:

Jim-Linda wrote:

A number of errors in this statement.. There is NO fuse under the black cover, there are however, a 120vac t/stat on the left side and a 12vdc t/stat on the right side. Both have a resettable "button" on the top stat. There is nothing to visually check, except maybe a burnt wire. Next, the element will open up almost instantly if no water is in the tank.

on a SUBURBAN water heater....

the high limit "wire" WILL melt (like a fuse) BY DESIGN - to interrupt power to the heating element, its there for the very purpose of preventing damage to the electric element.

you can VISUALLY see the wire/fuse when you remove the black cover which has the reset switches on it.

IF the high limit melts the fuse/wire, you can NOT heat water (via the 120vac element).

I know, because this has happened to me, if the fuse/wire is "OPEN" simply replace it (and you should be heating water via the electric element).

I have replaced 4-5 t/stats over the years on SUBURBAN HEATERS and have yet to see a fuse/fusible link or other device as you claim. May be getting blind, but after replacing the stat, the element came back to life.

Jim-Linda wrote:

A number of errors in this statement.. There is NO fuse under the black cover, there are however, a 120vac t/stat on the left side and a 12vdc t/stat on the right side. Both have a resettable "button" on the top stat. There is nothing to visually check, except maybe a burnt wire. Next, the element will open up almost instantly if no water is in the tank.

on a SUBURBAN water heater....

the high limit "wire" WILL melt (like a fuse) BY DESIGN - to interrupt power to the heating element, its there for the very purpose of preventing damage to the electric element.

you can VISUALLY see the wire/fuse when you remove the black cover which has the reset switches on it.

IF the high limit melts the fuse/wire, you can NOT heat water (via the 120vac element).

I know, because this has happened to me, if the fuse/wire is "OPEN" simply replace it (and you should be heating water via the electric element).

I had a similar issue. My grand daughters were playing in the camper and accidentally turned the gas WH switch on without any water in it. I did not notice this until the next afternoon when I happened to walk by and heard the water heater lighting. It apparently had been cycling overnight and into the next day. So far I have not had any problems with it, although it has not been used very much. I hope that the glass lining has not been cracked. I too thought that the high limit switch would have tripped, but it did not. This is a suburban 6 gal, electronic ignition model. Lesson learned.

Most likely the electric element is shot, about $25 to replace, you can get a better one that will go about 60 seconds without water, but without water most likely burned up.

Damage to the tank from gas without water hard to tell.

When charging water system after a drain, I open the pressure relief valve until water comes out in a stream, cuts down on the messy spitting at the faucets.

bshpilot wrote:
their are fail safe "high limit" thermostatic "fuse" that should prevent you from doing any serious damage to the water heater or heater element.

does the water get hot now (that the tank is full) ? on electric and gas ? if not try resetting the fuse

if the water will not heat then try resetting the (electric cut off) ECO / hi-limit fuse (identified by a black cover w/ two round "buttons" on it (accessible from the outside / back of the heater).

if the eco/hi-limit fuse reset doesnt correct the problem, I would pull the (black) cover to visually inspect the fuse to see if it is burnt/open - there is one fuse pre side (gas & electric) - the fuses are easily replaced and cost about 20 bucks each.

If you have the type of water heater that uses a sacrificial anode rod (suburban) - i highly recommend that you drain the water heater if you store the water heater frequently. The anode rod (about 10 bucks) needs to be checked for erosion & replaced at least annually if not more frequently (determined by how often the water heater is left full of water).

if the annde rod is not replace, eventually corrosion will build up on the heating element and could require replacement (10-15 bucks).

Heres a nice trouble shooting guide someone wrote up that will help - http://trekin.digital-digs.net/Share%20PDF/Water%20Heater%20Troubleshooting%20-%20Suburban%20V1.1.pdf

A number of errors in this statement.. There is NO fuse under the black cover, there are however, a 120vac t/stat on the left side and a 12vdc t/stat on the right side. Both have a resettable "button" on the top stat. There is nothing to visually check, except maybe a burnt wire. Next, the element will open up almost instantly if no water is in the tank.

dbbls wrote:
If it is an Atwood heater it may not have been damaged. The electric elements they use will not burn out if there is no water in the tank, however, I am not sure how long they will last without water. Try it on electric only and if it heats, you are OK.

suburban water heaters shouldn't burn the electric element out either - thats the job of the Hi-Limit / EOC fuse. The EOC / Hi-Limit fuse should "pop" & prevent failure of the electric heating element.

there is also a Hi-Limit / EOC fuse for the gas side too - to prevent over heating when no water is present in the tank.

If it is an Atwood heater it may not have been damaged. The electric elements they use will not burn out if there is no water in the tank, however, I am not sure how long they will last without water. Try it on electric only and if it heats, you are OK.

their are fail safe "high limit" thermostatic "fuse" that should prevent you from doing any serious damage to the water heater or heater element.

does the water get hot now (that the tank is full) ? on electric and gas ? if not try resetting the fuse

if the water will not heat then try resetting the (electric cut off) ECO / hi-limit fuse (identified by a black cover w/ two round "buttons" on it (accessible from the outside / back of the heater).

if the eco/hi-limit fuse reset doesnt correct the problem, I would pull the (black) cover to visually inspect the fuse to see if it is burnt/open - there is one fuse pre side (gas & electric) - the fuses are easily replaced and cost about 20 bucks each.

If you have the type of water heater that uses a sacrificial anode rod (suburban) - i highly recommend that you drain the water heater if you store the water heater frequently. The anode rod (about 10 bucks) needs to be checked for erosion & replaced at least annually if not more frequently (determined by how often the water heater is left full of water).

if the annde rod is not replace, eventually corrosion will build up on the heating element and could require replacement (10-15 bucks).

Heres a nice trouble shooting guide someone wrote up that will help - http://trekin.digital-digs.net/Share%20PDF/Water%20Heater%20Troubleshooting%20-%20Suburban%20V1.1.pdf