Water Heater Question (Electrical/Plumbing)

[Jeff-C175 7,202]

20 hours ago, wh500special said:

it’s possible that it wouldn’t have tripped a GFCI either. 

 

That's somewhat doubtful.  He said he heard 'sizzling' so that means there was SOME current flow.  The water in that little pool that we saw was heavily 'tainted' with rust.  I believe there was enough conductivity to trip a GFCI breaker.  It only take a few milliamps to do so.

 

GFCI works by measuring the difference of current between the HOT and the NEUTRAL.  Any difference means that SOME current is bypassing the 'normal' path and going to ground.

 

As for tap water having no conductivity... well, ALL tap (and well) water is not pure.  In theory, distilled water is pure and should have no conductivity.  

 

The powered anode on my water heater is current regulated at 15 milliamps.  The DC voltage across that anode is approximately 22 VDC.  If 22 VDC can draw 15 milliamps, there would certainly be enough current flow to ground to trip a GFCI at 240 VAC.

 

Would you want to stand in a puddle and grab a 240 VAC line?  I think not!

 

[Pullstart 62,881]

@Racinbob you are correct that regulators and gas meters have a huge factor on these.  Natural gas manifold pressure usually runs 4-4.5 inches of water column and LP, 10” at the appliance.  The home piping runs typically 1-2” higher pressure.  In some cases, a 2 lb. regulator can get installed on the home, then individual 6/11” regs. at each point of use will help with throughput issues.

 

I can’t say that Mike and Cas are wrong, because there is no wrong in this manner.  Each situation has it’s pros and cons and each homeowner needs to make their right decision.  It sure has been a great discussion and there are valid points on each side.  I do realize that hydronic heating is more prevalent in the north eastern US than the rest of the country.  Boilers and tankless kind of use the same technology, so maybe there is a more intricate support system as well.

[WHX?? 48,815]

Because they teched  the snot out of them Steve again in IMHO. .. older ones like Cas and Skunky  has ...they don't make them like that anymore. You gonna repair that flat screen TV when it takes a dump? ... thought not. New appliances when we buy them today have a very set life expectancy. Note how Mike said he's got spares on the shelf That's just my take.... Kev @pullstart very correct on the gas requirement. Many older natural gas meters cannot handle the load requirement.  

[squonk 41,118]

My heater is 8 yrs. old. Not that old. Wife wanted it and we have kept track of the costs since install. I was going thru the tank models every 5 years. I had to remove the temperature controls every 2 years and de-liming the probe. PITA. De-scaling a tankless, piece of cake. With the vent height issues I had to be careful with the piping and had to replace the heater venting and furnace venting every 3 years. Now without the water heater tied into the furnace vent It has lasted over 5 before I see any rust. Another 2 years this heater will have paid for itself including the spare parts I have on hand.

 

And you could line up all of Jim's tractors and I could power wash them all and still have hot water coming! 

[Pullstart 62,881]

2 minutes ago, squonk said:

And you could line up all of Jim's tractors and I could power wash him and all his tractors and still have hot water coming! 

But you’ll still never get that Up Nort’ hunt camp stink outta him!

[cschannuth 3,816]

At the risk of opening another can of worms what are everyone’s thoughts on electric on-demand water heater‘s? My son is buying a piece of property and he’s going to put a metal building on it that will be used for a shop and storage. However, initially he’s going to build out a small portion of it as a living space that he will live in until he builds a home on the property in the future. There’s no gas available and I don’t think he wants to set an LP tank at this time. It would basically be a one bedroom or a studio style apartment with a small kitchenette, laundry “closet”, and one bathroom. Eventually that will be turned into a workshop if he ever finds a good woman and builds a house.

[WHX?? 48,815]

1 minute ago, cschannuth said:

electric on-demand water heater‘s?

Very pricey to run in our area Craig... our electric rates suck. Would guess prone to liming up too. 

 

14 minutes ago, squonk said:

power wash them all and still have hot water coming!

This is true we have one at the shop and can wash our trucks all day. 

[cschannuth 3,816]

12 minutes ago, WHX24 said:

 

  12 minutes ago, cschannuth said:

electric on-demand water heater‘s?

Very pricey to run in our area Craig... our electric rates suck. Would guess prone to liming up too. 

 

 

 

We actually have very low electric rates through a co-op and it would only be him living in the place so we were hoping that would limit some of those concerns but they were the concerns that we had also.  I grew up with electric tank water heaters and they used to drive us crazy especially with the hard water in our area. I’ve had a 50 gallon Bradford White power vent gas water heater and it has run flawlessly for the last 25 years. Also we can all take showers at the same time and/or one right after the other and we still have a ton of hot water so it’s been a good experience. 

[squonk 41,118]

32 minutes ago, pullstart said:

But you’ll still never get that Up Nort’ hunt camp stink outta him!

Nu-Calgon Nu Brite will! 

[Pullstart 62,881]

4 minutes ago, cschannuth said:

 

We actually have very low electric rates through a co-op and it would only be him living in the place so we were hoping that would limit some of those concerns but they were the concerns that we had also.  I grew up with electric tank water heaters and they used to drive us crazy especially with the hard water in our area. I’ve had a 50 gallon Bradford White power vent gas water heater and it has run flawlessly for the last 25 years. Also we can all take showers at the same time and/or one right after the other and we still have a ton of hot water so it’s been a good experience. 

25 years old... power vent... it must have a Honeywell “Smart Valve” or maybe a Robertshaw pressure switch gas valve?  That’s old school right there!

There is a company called “Quick Shot” I believe that builds the majority of electric instantaneous.  They are economical and small, but have many cheap components.  There is another company called Keltech, recently acquired by Bradford White who makes much larger electric instantaneous than Quick Shot but much more durable and built with superior materials.  Of course, Keltech water heaters come with a price to reflect the quality...

 

[WHX?? 48,815]

9 minutes ago, cschannuth said:

Bradford White power vent gas water heater and it has run flawlessly for the last 25 years.

Hear that Kev?!?!? 

[Pullstart 62,881]

11 minutes ago, WHX24 said:

Hear that Kev?!?!? 

yeah.  I’d like to see a picture of that.  Old ones used a pressure tap so when the atmospheric gas valves with a standing pilot and thermocouple fired on a call for heat, they would excite a series of switches turning the blower on and proving flow, then open a solenoid allowing the burner to light.  Real crude, but pretty proven.

[wh500special 2,183]

59 minutes ago, Jeff-C175 said:

 

That's somewhat doubtful.  He said he heard 'sizzling' so that means there was SOME current flow.  The water in that little pool that we saw was heavily 'tainted' with rust.  I believe there was enough conductivity to trip a GFCI breaker.  It only take a few milliamps to do so.

 

GFCI works by measuring the difference of current between the HOT and the NEUTRAL.  Any difference means that SOME current is bypassing the 'normal' path and going to ground.

 

As for tap water having no conductivity... well, ALL tap (and well) water is not pure.  In theory, distilled water is pure and should have no conductivity.  

 

The powered anode on my water heater is current regulated at 15 milliamps.  The DC voltage across that anode is approximately 22 VDC.  If 22 VDC can draw 15 milliamps, there would certainly be enough current flow to ground to trip a GFCI at 240 VAC.

 

Would you want to stand in a puddle and grab a 240 VAC line?  I think not!

 

 

If I had to bet whether a GFCI would trip or not in this situation, I'd be with you on this and would bet every time that it would indeed trip.  But weird things happen with stray currents when water is involved.  Although I've never used one I would imagine a 240V GFCI breaker is looking for leakage to ground and not a low current path between the two hot conductors that are immersed in the bath.  The current will take the easiest path and it might just be flowing between the two hots since the driving force between them is twice as high as it is to ground.  A GFCI would probably just see this as load.  This is moot of course since Bob doesn't have a GFCI breaker on there.

 

I'd normally think too that there would be enough stuff dissolved in that little pan that the water would be pretty conductive, but it's hard to be sure.  I think most oxide products tend to have poor conductivity (if any) and don't dissociate well in water but my chemistry is so far in my past that I don't remember.   But this is why I was aiming at that water being from condensation instead of tap water.

 

Our retired EE here at work was fooling around deliberately trying to flow current through our St. Louis municipal tap water with 208V and had to add salt to the water to get it to go.  This was a big surprise to all of us.  Still, I wouldn't count on the water not being conductive nor stand in that puddle you mention!

 

I liken this to the same situation that we see year after year when unfortunate swimmers are shocked when swimming around boat docks and moored boats in freshwater lakes.  The water isn't conductive enough to support wholesale electrical current flow but there are localized spots here and there that do.  Solutes in low concentrations make things behave in surprising ways.

 

This might be one of those oddball cases that would be hard to replicate.

 

Now, why did he get burned?  Was that from the little electrical heater that was created in that enclosure?

 

Steve

[wh500special 2,183]

Thanks for the input on the "why not recommend the tankless?" question.

 

So I see that as a retrofit, they have a lot a "watch outs" compared to legacy solutions.  That's kind of what I expected the issues to be, but I can appreciate the electronic complexity of them creating reliability issues.

 

Last year about this time I decided it was time to replace my 10 year old 50 gallon electric water heater with a new one since it had corroded horribly on the one of the inlet or outlet pipes on top.  The rusty crust was moist so something was going on and I wanted to replace it at my leisure before it exploded in the basement and flooded all of my WH paraphernalia.

 

I really wanted to add a gas tankless.  The gas line was already there feeding the furnace and it's a 1" pipe all the way back to the meter.  Not sure why the builder went so big, but that's what I have.  My issue was the amount of work involved with running the inlet air and vent PVC pipes, rerouting the plumbing, and putting in a drain line.  It was just too much hassle so I replaced it with another electric tank unit.  The best place for it is in the center of the basement which translated to long pipe runs to get the air and exhaust in and out.  And I have walls and ceilings in the way no matter what direction I go.

 

So, back to an electric tank unit.

 

I did end up with the most complicated electric water heater I've ever seen though.  It's one of those heat pump models.  So it steals heat from the basement and puts it in the water.  It also has the standard electrical elements in it too in case the heat pump can't keep up.  Had it not been on clearance at Menards, had the additional 11% rebate, and had the $300 tax credit I wouldn't have bought it.  It ended up being cheaper than a standard 50 gallon electric.

 

I don't have a lot of confidence that this will be a 20-year trouble free installation, but I'm very happy with it so far.  since it's a little air conditioner sitting there running it dehumidifies the basement for me (good), cools the basement (in the summer, this is a bonus), and my electric bill has dropped about $15/month (good).  I thought I might have to switch it over to electric heating through the winter since cooling the basement isn't an advantage but it turned out not to be necessary.  Effectively, it means I'm heating my water with gas in the winter since my gas furnace sits in the same utility area with it and yet my gas bills remained about the same as before.

 

I'm not sure I would have bought this had it not been for the great overall price I got due to it being a clearance model, but I like it.  After having it a while, I'm kind of thinking it wasn't a bad deal.

 

I still kind of pine for a tankless though.

 

Steve

 

 

[Jeff-C175 7,202]

55 minutes ago, wh500special said:

I would imagine a 240V GFCI breaker is looking for leakage to ground and not a low current path between the two hot conductors that are immersed in the bath.

 

Yes, you have a good imagination!  

 

Just the name of the device tells us this is fact.  Ground Fault Circuit Interrupter.  Inside these devices are a pair of toroidal current transformers.  In a 120VAC device the transformers are around the HOT and the NEUTRAL.  In a 240VAC device, around the two HOTs.  The 240VAC circuit breakers require the NEUTRAL 'pigtail' to be connected inside the panel board but the device being powered does not need the NEUTRAL connection (as in water heaters).

 

A small comparator circuit measures both and any difference in the two currents is presumed to be a Ground Fault and the device opens a latching relay mechanism.

 

The problem in Bob's situation that there was nowhere near the 30 Amps required to open the breaker.  And in fact, current flow between the HOT wires is not even a fault at all !  But SOME of that current was certainly flowing through Ground and presumably should have been enough to trip a GFCI device.

 

1 hour ago, wh500special said:

Was that from the little electrical heater that was created in that enclosure?

 

Could be that the little pool of water was a tiny electric tea kettle!  

[WHX?? 48,815]

36 minutes ago, wh500special said:

1" pipe all the way back to the meter.

Pretty standard for natural gas to be brought in a single family dwelling with that. 3/4" for LP gas. 

 

39 minutes ago, wh500special said:

one of those heat pump models. 

Our electric co-op pushes those big time. I just could never get buy a refrigeration system on a water heater! I can see help drying out the basement tho. 

[Handy Don 12,232]

FWIW, we have a hydronic heating system where the water heater provides both domestic HW and water to circulate through a radiator core in an air handler for heating the house (plus a two-zone electric-actuated damper system).

 

I chose a 100k BTU high efficiency gas 32-gal tank unit with electronic ignition and powered outside air inlet/outlet. It handles two or more uses (showers, washing machine, house heat, etc.) at the same time handily. The house's gas piping has sufficient size since our stove, oven, and dryer are all gas.

 

Amusingly, when the utility initially saw the plans for our super-insulated, solar HW paneled house (in '83), they refused to install gas since they thought heat-only usage would not give them a good payback. Only when we confirmed the other gas appliances did they agree. Whew! Now, new construction and conversion hookups are being restricted due to limited gas transmission capacity into our area (made even more severe after Friday's shutdown of Entergy's Indian Point nuclear power plant).

 

[Jeff-C175 7,202]

36 minutes ago, Handy Don said:

our super-insulated, solar HW paneled house

 

Have you ever calculated how many BTU / SQ FT / DEGREE DAY your house needs for heating?   It's been a while since I did mine, but something like 12 comes to mind.

 

A friend owns a state of the art home that he could heat with a candle.  

 

[Handy Don 12,232]

5 hours ago, Jeff-C175 said:

 

Have you ever calculated how many BTU / SQ FT / DEGREE DAY your house needs for heating?   It's been a while since I did mine, but something like 12 comes to mind.

 

A friend owns a state of the art home that he could heat with a candle.  

 

I did all sorts of calculations, including return on investment but the only one that sticks in my head is the loss rate calculation -- 35,000 BTU per hour at 10º F since I used that to size my backup wood burning stove. Heated space is just about 3,500 sq. ft. The rate would have been lower, but I insisted on decent sized windows (did get coated glass, though)!

Edited May 3, 2021 by Handy Don

[Jeff-C175 7,202]

2 hours ago, Handy Don said:

35,000 BTU per hour at 10º F

 

2 hours ago, Handy Don said:

Heated space is just about 3,500 sq. ft

 

BTU / SQ FT / DD is difficult to run the numbers because it requires being able to measure fuel flow to the heating appliance only, not something easy to do with gas.  With fuel oil, if you know the nozzle size and oil pressure by using an hour meter it makes it pretty easy.  I do burn fuel oil, so it was easy for me.

 

Your heat loss is pretty outstanding for a home that size!  35K BTU is a bit less than my heat loss at HALF the square footage!  As I recall it was around 45K at 10°F.  I installed the smallest oil fired boiler I could find, which was 64K.  The boiler it replaced was 150K !!!

 

BUT, we digress... sorry guys!

[tom2p 2,394]

8 hours ago, Jeff-C175 said:

 

Have you ever calculated how many BTU / SQ FT / DEGREE DAY your house needs for heating?   It's been a while since I did mine, but something like 12 comes to mind.

 

A friend owns a state of the art home that he could heat with a candle.  

 

we are on the opposite end of the efficiency scale 

 

we have an early 50's brick house with a new revolutionary insulating material called 'Celotex'    lol

 

Edited May 4, 2021 by tom2p

[Handy Don 12,232]

2 hours ago, Jeff-C175 said:

Your heat loss is pretty outstanding for a home that size!  35K BTU is a bit less than my heat loss at HALF the square footage!  

BUT, we digress... sorry guys!

The house we left was 1,500 sq. ft.  -- utility bills in the new place were slightly lower.

But getting there was not free. 10.5" insulation in double-framed wall (requiring custom woodwork at door and window penetrations--took me weeks to complete), 30" insulation in attic, framed and insulated basement walls, carefully sealed vapor barriers, e-coated window glass, and more. Thankfully my spouse and I were on the same page about investing for the long gain and the payback has been there. 

Leaving that subject!

Edited May 4, 2021 by Handy Don

[squonk 41,118]

5 hours ago, tom2p said:

we are on the opposite end of the efficiency scale 

 

we have an early 50's brick house with a new revolutionary insulating material called 'Celotex'    lol

 

I'm lower than that. 250 yr. old house with blown in insulation. 

[Racinbob 11,081]

@rmaynard I'll bet you never imagined that this thread would generate so many posts. What brand is your electrical panel? I've personally experienced situations in line with this with one particular brand. There's still way more than there should be out there. 

[Jeff-C175 7,202]

6 hours ago, squonk said:

I'm lower than that. 250 yr. old house with blown in insulation. 

 

Quote

Location: Waterloo 

 

Do you have a sign on the door that reads: "Napolean Slept Here" ?   <-- see what I did there?  

 

 

Edited May 4, 2021 by Jeff-C175