Home Repair (alt.home.repair) For all homeowners and DIYers with many experienced tradesmen. Solve your toughest home fix-it problems.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 6
Default Electric hot water tanks - thermostat

I have two 75 gallon(US) electric hot water tanks plumbed in parallel.
House is new - we moved in 16 months ago and starting about 3 weeks ago
there has been a shortage of hot water. We are running out of hot water
sooner than we used to with similar use patterns. Water temp is plenty
hot to start with and for quite a while. The problem is about a one-third
to one-quarter loss of capacity. We are now running out of hot water when
everyone is taking a shower, some of us like long showers. If only 2 or 3
people shower there is no problem. For over a year we could never run out
of hot water but now we do, fairly often.

I think the dip tubes must be fine or we would have a problem with the
first shower, not the fourth.

I tested the elements with a continuity tester and all four lit up the
light. I also tested for resistance and got about 14.3 ohms for all 4
elements. That's why I think a thermostat is the problem.

Voltage is 240 and there are 4 thermostats. The make of the tanks is
Giant, model 172ETE-3F7M, 4500 watt elements.

The upper wire block has 7 screws - 4 in the left column and 3 in the
right column, there is a high limit reset button which has no effect on
problem. There is a yellow and a blue wire to the upper element and a red
wire to the lower element and a black wire to the lower thermostat. There
is a temp setting screw.

The lower wire block has 2 screws - black wire in and a black wire to the
element.

I downloaded the manufacturers wiring diagram and the connections match
the diagram. Worked fine for over a year so I assume connections are OK.

Can someone explain how to test and determine which thermostat is bad? Or
could there be a bad element?

Thanks,

Reinhard
  #2   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 6,199
Default Electric hot water tanks - thermostat

On Feb 16, 9:03�pm, Reinhard wrote:
I have two 75 gallon(US) electric hot water tanks plumbed in parallel.
House is new - we moved in 16 months ago and starting about 3 weeks ago
there has been a shortage of hot water. We are running out of hot water �
sooner than we used to with similar use patterns. Water temp is plenty
hot to start with and for quite a while. The problem is about a one-third
to one-quarter loss of capacity. We are now running out of hot water when
everyone is taking a shower, some of us like long showers. If only 2 or 3
people shower there is no problem. For over a year we could never run out
of hot water but now we do, fairly often.

I think the dip tubes must be fine or we would have a problem with the
first shower, not the fourth.

I tested the elements with a continuity tester and all four lit up the
light. I also tested for resistance and got about 14.3 ohms for all 4
elements. That's why I think a thermostat is the problem.

Voltage is 240 and there are 4 thermostats. The make of the tanks is
Giant, model 172ETE-3F7M, 4500 watt elements.

The upper wire block has 7 screws - 4 in the left column and 3 in the
right column, there is a high limit reset button which has no effect on
problem. There is a yellow and a blue wire to the upper element and a red
wire to the lower element and a black wire to the lower thermostat. There
is a temp setting screw.

The lower wire block has 2 screws - black wire in and a black wire to the
element.

I downloaded the manufacturers wiring diagram and the connections match
the diagram. Worked fine for over a year so I assume connections are OK.

Can someone explain how to test and determine which thermostat is bad? Or
could there be a bad element?

Thanks,

Reinhard


use a clamp on ampmeter. that will tell you if both tanks are drawing
the same current.

you might have a bad thermostat or bad element.

and always use a analog meter, not digital.

the digital meters are so sensitive the readings can be wrong
  #3   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 5
Default Electric hot water tanks - thermostat

a bit off topic but did you ever think of going to a tankless system? it is
hot water on demand. check out http://www.foreverho****er.com/
"Reinhard" wrote in message
...
I have two 75 gallon(US) electric hot water tanks plumbed in parallel.
House is new - we moved in 16 months ago and starting about 3 weeks ago
there has been a shortage of hot water. We are running out of hot water
sooner than we used to with similar use patterns. Water temp is plenty
hot to start with and for quite a while. The problem is about a one-third
to one-quarter loss of capacity. We are now running out of hot water when
everyone is taking a shower, some of us like long showers. If only 2 or 3
people shower there is no problem. For over a year we could never run out
of hot water but now we do, fairly often.

I think the dip tubes must be fine or we would have a problem with the
first shower, not the fourth.

I tested the elements with a continuity tester and all four lit up the
light. I also tested for resistance and got about 14.3 ohms for all 4
elements. That's why I think a thermostat is the problem.

Voltage is 240 and there are 4 thermostats. The make of the tanks is
Giant, model 172ETE-3F7M, 4500 watt elements.

The upper wire block has 7 screws - 4 in the left column and 3 in the
right column, there is a high limit reset button which has no effect on
problem. There is a yellow and a blue wire to the upper element and a red
wire to the lower element and a black wire to the lower thermostat. There
is a temp setting screw.

The lower wire block has 2 screws - black wire in and a black wire to the
element.

I downloaded the manufacturers wiring diagram and the connections match
the diagram. Worked fine for over a year so I assume connections are OK.

Can someone explain how to test and determine which thermostat is bad? Or
could there be a bad element?

Thanks,

Reinhard



  #4   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 6,199
Default Electric hot water tanks - thermostat

On Feb 16, 10:22�pm, "Bob Bob" wrote:
a bit off topic but did you ever think of going to a tankless system? it is
hot water on demand. check outhttp://www.foreverho****er.com/"Reinhard" wrote in message

...



I have two 75 gallon(US) electric hot water tanks plumbed in parallel.
House is new - we moved in 16 months ago and starting about 3 weeks ago
there has been a shortage of hot water. We are running out of hot water
sooner than we used to with similar use patterns. Water temp is plenty
hot to start with and for quite a while. The problem is about a one-third
to one-quarter loss of capacity. We are now running out of hot water when
everyone is taking a shower, some of us like long showers. If only 2 or 3
people shower there is no problem. For over a year we could never run out
of hot water but now we do, fairly often.


I think the dip tubes must be fine or we would have a problem with the
first shower, not the fourth.


I tested the elements with a continuity tester and all four lit up the
light. I also tested for resistance and got about 14.3 ohms for all 4
elements. That's why I think a thermostat is the problem.


Voltage is 240 and there are 4 thermostats. The make of the tanks is
Giant, model 172ETE-3F7M, 4500 watt elements.


The upper wire block has 7 screws - 4 in the left column and 3 in the
right column, there is a high limit reset button which has no effect on
problem. There is a yellow and a blue wire to the upper element and a red
wire to the lower element and a black wire to the lower thermostat. There
is a temp setting screw.


The lower wire block has 2 screws - black wire in and a black wire to the
element.


I downloaded the manufacturers wiring diagram and the connections match
the diagram. Worked fine for over a year so I assume connections are OK.


Can someone explain how to test and determine which thermostat is bad? Or
could there be a bad element?


Thanks,


Reinhard- Hide quoted text -


- Show quoted text -


tankless create way more troubles than they solve.....

now this poster has electric tanks.

electric tankless require 200 amps for decent water flow with cold
input weather.

few will want to pay for a expensive service upgrade with 2 main
panels one just to heat water..........

the OP has a working system up till recently when something failed.
  #5   Report Post  
Posted to alt.home.repair
Pat Pat is offline
external usenet poster
 
Posts: 657
Default Electric hot water tanks - thermostat

On Feb 16, 9:03*pm, Reinhard wrote:
I have two 75 gallon(US) electric hot water tanks plumbed in parallel.
House is new - we moved in 16 months ago and starting about 3 weeks ago
there has been a shortage of hot water. We are running out of hot water *
sooner than we used to with similar use patterns. Water temp is plenty
hot to start with and for quite a while. The problem is about a one-third
to one-quarter loss of capacity. We are now running out of hot water when
everyone is taking a shower, some of us like long showers. If only 2 or 3
people shower there is no problem. For over a year we could never run out
of hot water but now we do, fairly often.

I think the dip tubes must be fine or we would have a problem with the
first shower, not the fourth.

I tested the elements with a continuity tester and all four lit up the
light. I also tested for resistance and got about 14.3 ohms for all 4
elements. That's why I think a thermostat is the problem.

Voltage is 240 and there are 4 thermostats. The make of the tanks is
Giant, model 172ETE-3F7M, 4500 watt elements.

The upper wire block has 7 screws - 4 in the left column and 3 in the
right column, there is a high limit reset button which has no effect on
problem. There is a yellow and a blue wire to the upper element and a red
wire to the lower element and a black wire to the lower thermostat. There
is a temp setting screw.

The lower wire block has 2 screws - black wire in and a black wire to the
element.

I downloaded the manufacturers wiring diagram and the connections match
the diagram. Worked fine for over a year so I assume connections are OK.

Can someone explain how to test and determine which thermostat is bad? Or
could there be a bad element?

Thanks,

Reinhard


This is slightly OT, but I have 8-unit apartment complexes that run
off of 150 gal electric tanks and no one ever complains about lack of
hot water.


  #6   Report Post  
Posted to alt.home.repair
mm mm is offline
external usenet poster
 
Posts: 7,824
Default Electric hot water tanks - thermostat

On Sat, 16 Feb 2008 20:28:04 -0800 (PST), Pat
wrote:



This is slightly OT, but I have 8-unit apartment complexes that run
off of 150 gal electric tanks


More than one? How many?

and no one ever complains about lack of
hot water.


  #7   Report Post  
Posted to alt.home.repair
mm mm is offline
external usenet poster
 
Posts: 7,824
Default Electric hot water tanks - thermostat

On Sun, 17 Feb 2008 02:03:48 GMT, Reinhard wrote:


The lower wire block has 2 screws - black wire in and a black wire to the
element.

I downloaded the manufacturers wiring diagram and the connections match
the diagram. Worked fine for over a year so I assume connections are OK.

Can someone explain how to test and determine which thermostat is bad? Or
could there be a bad element?


Can you close off the output from one tank at a time and see if the
other tank is putting out hot water? They might both be, but if not,
that would be a big clue. Or close the input to one tank.

Of course there could be a bad element. My impression of my WH is
that there was no need to disconnect any wires from the elements to do
a good measurement of the resistance, but certainly in some things,
like radio where parts are in parallel, that isn't always true. you
should re-examine the wiring diagram to make sure there isn't some
alternate path that would make an open element look like a working
one.

In my case, and yours since like mine, there are also only two wires
going to the bottom thermostat/element combo, it will be easier to
measure the bottom than the top. If no one has used hot water for an
hour, the water should be hot and the lower thermostat should be open.
Turn off the power and with the meter on 240AC or higher, measure for
AC voltage across the thermostat. Yes, I know I just told you to turn
off the power, but some day you will forget to do that. If you
attempt to measure resistance when the power is still on, you'll
likely burn out your meter, if nothing worse. So always measure for
voltage before measuring for resistance.

When there is no voltage, measure the resistance across the
thermostat. It should be infinite, meaning that it is open and that
means one of the leads from the lower element doesn't connect to
anything now. So now you can measure the resistance of the lower
element without there being an alternate path, and you will get a
correct reading. Anything lower than infinity is likely to be good.

Also measure the resistance from the ground wire or the metal case of
the water heater to each of the wires on the heating element. It's
possible for the element to short against, I guess, the element cover,
and to make the case "hot". If so, the element has to be replaced. If
the element is 14 ohms, then whatever the resistance between one of
the screws and the case is, unless it is infinite (as it should be)
the resistance between the case and the other screw should be 14 ohms
higher, or lower.

Thanks,

Reinhard


I'm nowhere near a pro, but aiui, in a some wheaters the upper and
lower elements might run at the same time, but I think in most, the
upper element runs first to provide some wh at the top of the tank and
when it heats up a little, then the top thermostat sends the current
to the lower element which does most of the heating. The lower
thermostat turns that one off when the whole tank is hot enough.

Doesn't it say on the manu. wiring diagram something to indicate which
kind of system you have? The kind you have will determine what you
should look for.

My last wh had an LED connected across the upper element, so that one
could easily tell when it was on. (at least when there was power to
it. That didn't mean the element was working, but I never had doubts
that it was.) I was thinking of putting an LED across the bottom one
too this time, because I've had some of the same questions you have
now**. You probably don't have room for these when the covers are on,
but you could, when the power is off, connect lights like this
temporarily and see when power is going to each element. LEDs for AC
may be different from those for DC, i don't remenber. But the rating
will include 240 volts AC.

Or you can very carefully use a meter. I would, when the power is
off, make sure that the insulation isn't in the way of making
measurements, and for the lower element, I would sit on the floor so I
didn't fall over and fall into the waterheater. I would even consider
using jumper wires with alligator clips on both ends and connecting
these to the meter probes and the screws when the power is off, then
turning the power back on. I assume you are well acquainted with the
precautions you need for 240 volts. It's much more dangerous tan 110.


**But the new styrofoam? insulation around the thermostat left no easy
room for even the one LED, so instead now I have none.
  #8   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 1,563
Default Electric hot water tanks - thermostat


"Pat" wrote in message
...
On Feb 16, 9:03 pm, Reinhard wrote:
I have two 75 gallon(US) electric hot water tanks plumbed in parallel.
House is new - we moved in 16 months ago and starting about 3 weeks ago
there has been a shortage of hot water. We are running out of hot water
sooner than we used to with similar use patterns. Water temp is plenty
hot to start with and for quite a while. The problem is about a one-third
to one-quarter loss of capacity. We are now running out of hot water when
everyone is taking a shower, some of us like long showers. If only 2 or 3
people shower there is no problem. For over a year we could never run out
of hot water but now we do, fairly often.

I think the dip tubes must be fine or we would have a problem with the
first shower, not the fourth.

I tested the elements with a continuity tester and all four lit up the
light. I also tested for resistance and got about 14.3 ohms for all 4
elements. That's why I think a thermostat is the problem.

Voltage is 240 and there are 4 thermostats. The make of the tanks is
Giant, model 172ETE-3F7M, 4500 watt elements.

The upper wire block has 7 screws - 4 in the left column and 3 in the
right column, there is a high limit reset button which has no effect on
problem. There is a yellow and a blue wire to the upper element and a red
wire to the lower element and a black wire to the lower thermostat. There
is a temp setting screw.

The lower wire block has 2 screws - black wire in and a black wire to the
element.

I downloaded the manufacturers wiring diagram and the connections match
the diagram. Worked fine for over a year so I assume connections are OK.

Can someone explain how to test and determine which thermostat is bad? Or
could there be a bad element?

Thanks,

Reinhard


This is slightly OT, but I have 8-unit apartment complexes that run
off of 150 gal electric tanks and no one ever complains about lack of
hot water.

Residential electric water heaters use 2- 4.5 KW (standard) elements,
operating one at a time, to heat the water. Commercial electric water
heaters can use more and higher KW elements in the same size tanks, so they
have much faster recovery


  #9   Report Post  
Posted to alt.home.repair
jim jim is offline
external usenet poster
 
Posts: 206
Default Electric hot water tanks - thermostat

On Feb 17, 6:49*am, "RBM" wrote:
"Pat" wrote in message

...
On Feb 16, 9:03 pm, Reinhard wrote:





I have two 75 gallon(US) electric hot water tanks plumbed in parallel.
House is new - we moved in 16 months ago and starting about 3 weeks ago
there has been a shortage of hot water. We are running out of hot water
sooner than we used to with similar use patterns. Water temp is plenty
hot to start with and for quite a while. The problem is about a one-third
to one-quarter loss of capacity. We are now running out of hot water when
everyone is taking a shower, some of us like long showers. If only 2 or 3
people shower there is no problem. For over a year we could never run out
of hot water but now we do, fairly often.


I think the dip tubes must be fine or we would have a problem with the
first shower, not the fourth.


I tested the elements with a continuity tester and all four lit up the
light. I also tested for resistance and got about 14.3 ohms for all 4
elements. That's why I think a thermostat is the problem.


Voltage is 240 and there are 4 thermostats. The make of the tanks is
Giant, model 172ETE-3F7M, 4500 watt elements.


The upper wire block has 7 screws - 4 in the left column and 3 in the
right column, there is a high limit reset button which has no effect on
problem. There is a yellow and a blue wire to the upper element and a red
wire to the lower element and a black wire to the lower thermostat. There
is a temp setting screw.


The lower wire block has 2 screws - black wire in and a black wire to the
element.


I downloaded the manufacturers wiring diagram and the connections match
the diagram. Worked fine for over a year so I assume connections are OK.


Can someone explain how to test and determine which thermostat is bad? Or
could there be a bad element?


Thanks,


Reinhard


This is slightly OT, but I have 8-unit apartment complexes that run
off of 150 gal electric tanks and no one ever complains about lack of
hot water.

Residential electric water heaters use 2- 4.5 KW (standard) elements,
operating one at a time, to heat the water. Commercial electric water
heaters can use more and higher KW elements in the same size tanks, so they
have much faster recovery- Hide quoted text -

- Show quoted text -


Stagger your showers have you drained the sediment from the tanks and
cut the time save a bundle on Hydro never understood why people waste
so much mony on showers.
  #10   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 1,563
Default Electric hot water tanks - thermostat


"jim" wrote in message
...
On Feb 17, 6:49 am, "RBM" wrote:
"Pat" wrote in message

...
On Feb 16, 9:03 pm, Reinhard wrote:





I have two 75 gallon(US) electric hot water tanks plumbed in parallel.
House is new - we moved in 16 months ago and starting about 3 weeks ago
there has been a shortage of hot water. We are running out of hot water
sooner than we used to with similar use patterns. Water temp is plenty
hot to start with and for quite a while. The problem is about a
one-third
to one-quarter loss of capacity. We are now running out of hot water
when
everyone is taking a shower, some of us like long showers. If only 2 or
3
people shower there is no problem. For over a year we could never run
out
of hot water but now we do, fairly often.


I think the dip tubes must be fine or we would have a problem with the
first shower, not the fourth.


I tested the elements with a continuity tester and all four lit up the
light. I also tested for resistance and got about 14.3 ohms for all 4
elements. That's why I think a thermostat is the problem.


Voltage is 240 and there are 4 thermostats. The make of the tanks is
Giant, model 172ETE-3F7M, 4500 watt elements.


The upper wire block has 7 screws - 4 in the left column and 3 in the
right column, there is a high limit reset button which has no effect on
problem. There is a yellow and a blue wire to the upper element and a
red
wire to the lower element and a black wire to the lower thermostat.
There
is a temp setting screw.


The lower wire block has 2 screws - black wire in and a black wire to
the
element.


I downloaded the manufacturers wiring diagram and the connections match
the diagram. Worked fine for over a year so I assume connections are OK.


Can someone explain how to test and determine which thermostat is bad?
Or
could there be a bad element?


Thanks,


Reinhard


This is slightly OT, but I have 8-unit apartment complexes that run
off of 150 gal electric tanks and no one ever complains about lack of
hot water.

Residential electric water heaters use 2- 4.5 KW (standard) elements,
operating one at a time, to heat the water. Commercial electric water
heaters can use more and higher KW elements in the same size tanks, so
they
have much faster recovery- Hide quoted text -

- Show quoted text -


Stagger your showers have you drained the sediment from the tanks and
cut the time save a bundle on Hydro never understood why people waste
so much mony on showers.

I don't think people consider it a "waste", to spend their money on things
that they enjoy, whether it be long hot showers, steak dinners, or luxury
cars.




  #11   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 6,199
Default Electric hot water tanks - thermostat

On Feb 17, 4:38�am, mm wrote:
On Sun, 17 Feb 2008 02:03:48 GMT, Reinhard wrote:

The lower wire block has 2 screws - black wire in and a black wire to the
element.


I downloaded the manufacturers wiring diagram and the connections match
the diagram. Worked fine for over a year so I assume connections are OK.


Can someone explain how to test and determine which thermostat is bad? Or
could there be a bad element?


Can you close off the output from one tank at a time and see if the
other tank is putting out hot water? �They might both be, but if not,
that would be a big clue. �Or close the input to one tank.

Of course there could be a bad element. �My impression of my WH is
that there was no need to disconnect any wires from the elements to do
a good measurement of the resistance, but certainly in some things,
like radio where parts are in parallel, that isn't always true. �you
should re-examine the wiring diagram to make sure there isn't some
alternate path that would make an open element look like a working
one. �

In my case, and yours since like mine, there are also only two wires
going to the bottom thermostat/element combo, it will be easier to
measure the bottom than the top. � If no one has used hot water for an
hour, the water should be hot and the lower thermostat should be open.
Turn off the power and with the meter on 240AC or higher, measure for
AC voltage across the thermostat. �Yes, I know I just told you to turn
off the power, but some day you will forget to do that. �If you
attempt to measure resistance when the power is still on, you'll
likely burn out your meter, if nothing worse. �So always measure for
voltage before measuring for resistance. �

When there is no voltage, measure the resistance across the
thermostat. �It should be infinite, meaning that it is open and that
means one of the leads from the lower element doesn't connect to
anything now. �So now you can measure the resistance of the lower
element without there being an alternate path, and you will get a
correct reading. �Anything lower than infinity is likely to be good.

Also measure the resistance from the ground wire or the metal case of
the water heater to each of the wires on the heating element. �It's
possible for the element to short against, I guess, the element cover,
and to make the case "hot". �If so, the element has to be replaced.. If
the element is 14 ohms, then whatever the resistance �between one of
the screws and the case is, unless it is infinite (as it should be)
the resistance between the case and the other screw should be 14 ohms
higher, or lower.



Thanks,


Reinhard


I'm nowhere near a pro, but aiui, in a some wheaters the upper and
lower elements might run at the same time, but I think in most, the
upper element runs first to provide some wh at the top of the tank and
when it heats up a little, then the top thermostat sends the current
to the lower element which does most of the heating. �The lower
thermostat turns that one off when the whole tank is hot enough.

Doesn't it say on the manu. wiring diagram something to indicate which
kind of system you have? The kind you have will determine what you
should look for.

My last wh had an LED connected across the upper element, so that one
could easily tell when it was on. (at least when there was power to
it. That didn't mean the element was working, but I never had doubts
that it was.) �I was thinking of putting an LED across the bottom one
too this time, because I've had some of the same questions you have
now**. �You probably don't have room for these when the covers are on,
but you could, when the power is off, connect lights like this
temporarily and see when power is going to each element. � LEDs for AC
may be different from those for DC, i don't remenber. �But the rating
will include 240 volts AC.

Or you can very carefully use a meter. �I would, when the power is
off, make sure that the insulation isn't in the way of making
measurements, and for the lower element, I would sit on the floor so I
didn't fall over and fall into the waterheater. �I would even consider
using jumper wires with alligator clips on both ends and connecting
these to the meter probes and the screws when the power is off, then
turning the power back on. �I assume you are well acquainted with the
precautions you need for 240 volts. �It's much more dangerous tan 110.

**But the new styrofoam? insulation around the thermostat left no easy
room for even the one LED, so instead now I have none.


ahh LEDs are generally run on just a few volts max.

what your probably want are neon lamps, they can run on 120 or 240
volts

they use nearly no power, and last nearly forever
  #12   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 6,199
Default Electric hot water tanks - thermostat

i seriously doubt the tanks are sluged up since the house is only 16
months old
  #13   Report Post  
Posted to alt.home.repair
mm mm is offline
external usenet poster
 
Posts: 7,824
Default Electric hot water tanks - thermostat

On Sun, 17 Feb 2008 14:50:57 -0800 (PST), "
wrote:


Or you can very carefully use a meter. ?I would, when the power is
off, make sure that the insulation isn't in the way of making
measurements, and for the lower element, I would sit on the floor so I
didn't fall over and fall into the waterheater. ?I would even consider
using jumper wires with alligator clips on both ends and connecting
these to the meter probes and the screws when the power is off, then
turning the power back on. ?I assume you are well acquainted with the
precautions you need for 240 volts. ?It's much more dangerous tan 110.

**But the new styrofoam? insulation around the thermostat left no easy
room for even the one LED, so instead now I have none.


ahh LEDs are generally run on just a few volts max.


Well, some are made for higher and come with resistors to lower the
voltage to that, but I think you are still absolutely right wrt water
heaters. Thanks for the correction.

what your probably want are neon lamps, they can run on 120 or 240
volts


Yes, and they do fine with AC current. I've only seen led's on direct
current. I thought about that before I posted but then thought,
"Heck, it's a diode. It will just rectify the AC." But now I don't
know.

they use nearly no power, and last nearly forever


  #14   Report Post  
Posted to alt.home.repair
mm mm is offline
external usenet poster
 
Posts: 7,824
Default Electric hot water tanks - thermostat

On Sun, 17 Feb 2008 09:43:19 -0500, "RBM" wrote:


"jim" wrote in message
...
On Feb 17, 6:49 am, "RBM" wrote:

This is slightly OT, but I have 8-unit apartment complexes that run
off of 150 gal electric tanks and no one ever complains about lack of
hot water.

Residential electric water heaters use 2- 4.5 KW (standard) elements,
operating one at a time, to heat the water. Commercial electric water
heaters can use more and higher KW elements in the same size tanks, so
they
have much faster recovery- Hide quoted text -

- Show quoted text -


Stagger your showers have you drained the sediment from the tanks and
cut the time save a bundle on Hydro never understood why people waste
so much mony on showers.

I don't think people consider it a "waste", to spend their money on things
that they enjoy, whether it be long hot showers, steak dinners, or luxury
cars.


I solved that problem. I cook my steaks on the engine and take my
showers in the car.


  #15   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 6,199
Default Electric hot water tanks - thermostat

On Feb 18, 4:52�pm, "Stormin Mormon"
wrote:
When you're out of water, feel the pipes and see if one WH is still
delivering hot water.

As to the WH delivering cold, it still could be a bad dip tube.

As I understand WH, only one element is powered at a particular time. I'd
expect the lower element to show power / current for a while, and then the
upper one later. An infared thermometer is also a good idea, to see what
temp the thermostat is "seeing" in the tank.

--
Christopher A. Young
Learn more about Jesus
�www.lds.org
.

"Reinhard" wrote in message

...
I have two 75 gallon(US) electric hot water tanks plumbed in parallel.
House is new - we moved in 16 months ago and starting about 3 weeks ago
there has been a shortage of hot water. We are running out of hot water
sooner than we used to with similar use patterns. Water temp is plenty
hot to start with and for quite a while. The problem is about a one-third
to one-quarter loss of capacity. We are now running out of hot water when
everyone is taking a shower, some of us like long showers. If only 2 or 3
people shower there is no problem. For over a year we could never run out
of hot water but now we do, fairly often.

I think the dip tubes must be fine or we would have a problem with the
first shower, not the fourth.

I tested the elements with a continuity tester and all four lit up the
light. I also tested for resistance and got about 14.3 ohms for all 4
elements. That's why I think a thermostat is the problem.

Voltage is 240 and there are 4 thermostats. The make of the tanks is
Giant, model 172ETE-3F7M, 4500 watt elements.

The upper wire block has 7 screws - 4 in the left column and 3 in the
right column, there is a high limit reset button which has no effect on
problem. There is a yellow and a blue wire to the upper element and a red
wire to the lower element and a black wire to the lower thermostat. There
is a temp setting screw.

The lower wire block has 2 screws - black wire in and a black wire to the
element.

I downloaded the manufacturers wiring diagram and the connections match
the diagram. Worked fine for over a year so I assume connections are OK.

Can someone explain how to test and determine which thermostat is bad? Or
could there be a bad element?

Thanks,

Reinhard


use clamp on amp meter check current draw of both heaters after
drawing a lot of water, both should match


  #16   Report Post  
Posted to alt.home.repair
mm mm is offline
external usenet poster
 
Posts: 7,824
Default Electric hot water tanks - thermostat

On Mon, 18 Feb 2008 14:30:12 -0800 (PST), "
wrote:

use clamp on amp meter check current draw of both heaters after
drawing a lot of water, both should match


Two people have recommended that, but neither mentioned the difficulty
of using one, iiuc.

Don't you have to separate the two power leads to use a clamp-on, so
that it goes around only one of them? Otherwise don't the current in
each of the two wires going opposite directions cancel each other out?

You could open the top and pull out one of the wires. Is that what is
intended?
  #17   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 455
Default Electric hot water tanks - thermostat

"Stormin Mormon" wrote:

What's iiuc?



If I Understand Correctly
Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Aux. water tanks Robert Green Home Repair 26 May 3rd 06 05:48 PM
Water in oil tanks boden Home Repair 5 October 13th 05 04:00 AM
F/S Water tanks and other water bottling stuff JohnF Metalworking 1 May 20th 05 02:09 AM
Where to get thermostat for Craftmaster electric water heater? Rowland Home Repair 8 June 8th 04 09:10 PM
Electric water heating, cold water tanks and ceiling heating! David UK diy 5 January 13th 04 12:47 PM


All times are GMT +1. The time now is 12:25 PM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"