Electrical Service

I have a tankless hot water heater with the following requirements:

Voltage/Freq:240v/60

Wattage:21kw

Max amp load: 88

Min req circuit breaker: 2x60

Min wire size: 2x8 AWG copper (note:should be 2x6)



Amps to house is 200. Breaker box is 10 years old with space to add new breaker. The old 30 breaker will come out, new 2x60 in, and new wiring will need to be run approx 15 feet to location of old water heater.



Initial quotes from electricians via phone are all over the place and I have someone coming to house on Friday for a site estimate. In my understanding, the work is straight forward as stated above. What am I missing? Or what might the electricians be thinking I am not (besides pulling a $40 permit)?
      

Hi All,



Planning on installing a Zip contract 2 point of use overhead water heater, 10 litre 2kw.



Query can I use current mcb & rcb installed in distribution box which was used for 3kw immersion water heater.



If not can I use a 45amp 30ma mcb and if so what rcb rating should I also use.



I am assumming that the old water immersion circuit would be ok or would the rating be too strong being it 3kw as opposed to the now 2kw.



Cheers,

Nutrifix.
      

Can anyone please tell me what type of wire i need for my hot water heater?  Also is it going to be a double pole 30A breaker or is it just 120V  #10/2?
      

In a large bunkhouse we need to add a second range, water heater, and kitchen outlets.  The existing panel is 125 AMP (with breaker), and don't want to redo entire panel.  A consultant said to install a 200 AMP drop, with a panel to handle the additional load.  Would you then feed each of the panels from that drop as main panels, or use a new 200 AMP panel as the main, and the 125 as a sub-panel from that?  I assume in either instance, the grounding would be done as a 200 AMP service.  Just realized if each was a main panel, the new one couldn't exceed 75 Amps, or total would be over 200.  Any other ideas appreciated.
      

I am installing central air conditioner in our 80 year old house. Debating between one high velocity system or two conventional systems.



We have 100 amp service with an electric dryer, stove and oven. Water and heat is gas.



The HVAC contractor told me that he spoke with the electrician who assured him that we would not need to upgrade service but add in a sub-panel.



Any thoughts?



What are the risks of staying with current electrical service and adding A/C? What are the risks of upgrading to 200 amp with such old wiring? Is one high velocity system better than two conventional systems?



Note I am cross posting based on another question I had in the HVAC forum.



Thank you in advance for all your help.
      

Greetings,



I am looking to wire a sub-panel in my barn to support a general workshop.  Loads would include standard woodworking tools (including 220V table saw), welding, air compressor, etc.



The house has 200AMP main breaker and minimal in-house loads.  Dryer is gas, Oven and cooktop are gas.  Water heater is off the oil furnace.  I think the biggest single load is the well-pump and/or fridge compressor.  We do have sporadic toaster oven, hairdryers etc.  Otherwise its just lights, ceiling fans, flat-panel tv, stereo...



We had 4" conduit installed to the barn, so there is plenty of room to pull a big cable.  The entire run from the house panel to the barn totals around 155' (probably less, but rounding up)



My questions a



Can I pull a 100AMP sub-panel from my main house panel as described?


Would 4/0,4/0,4/0,2/0 aluminum service entrance cable be a good choice for this run?  Could I do it with something lighter?


Could I put an additional sub-panel in the garage (about halfway to the barn) by interrupting the run?  The garage subpanel would have a 220V plug for possible welding and/or electric car charging.  Would this require a separate run?


Are there any other considerations I should be thinking about in planning this?




Thanks for any thoughts you can share on this! 



Cheers,



pete
      

I have a small 19 gallon water heater in a small garage space, that was installed by some questionable handymen a few months back.  I just had the plumbing and septic finished so tested the hot water, only to find the element was already burned out.



I noticed however, that this 120v unit is wired via 10 gauge wire to a 30 amp double breaker.  This is questionable because I thought a 120v appliance would be wired to a single pole on the hot wire and run neutral to the neural panel area.



My question is, can I run the hot wire out of one side of the double breaker without safety issues, or should I definitely replace it with a single pole breaker?



I would normally not question the work, but everything these guys did already had to be adjusted, so I'm only naturally assuming this may need to be also.



If its safe, I would like to simply things and just connect the one hot and leave an open space in the other half of the double pole... Is this possible?



Thanks for your advice-
      

Hello All,



First post, working on a complete bare-stud remodel of my home, so I will try to be descriptive enough.  I have a 150 Amp service to the house (which I might upgrade later) with a meter socket and breakers outside.  I am running into the house (more than 10') to a 125 Amp 20 space ML.  I have too many 15 and 20 Amp circuits now for the panel and need to change it out.  The house is rather sprawling, so the rather than tie rooms together in a confusing way, I broke the circuits down per minimum requirements... almost none of them are near capacity.  I am going to run the big stuff back out to the exterior panel/service however I still need more space in my interior panel.  What I REALLY need is just a 40 circuit 125 Amp GE panel but I don't think those exist because (guessing) *most* 40 circuit scenarios need more amps.



What I wanted to do was upgrade to a 40 space panel (only been able to find a 200-Amp).  I realize I am still limited outside by the service and have already run 4/0 aluminum.  I know I am not going to go anywhere near the 200 Amp capacity, I just need the space.  Is this ok?  Any reason I shouldn't use a 200 Amp MB panel? 



Thanks!
      

Q1-

isn't rigid conduit supposed to bottom out in hub on new service panel? I thought so, installed mine and the threads look fine but only threaded in about 8 turns then stopped. Same on the other end.

Q2-

i'm trying to figure out how to brace my service entrance rigid conduit in my garage wall to my service panel. the conduit is 1 1/2 inch and the studs are 3 1/2 (2x4) so there's no room for cross bracing behind the rmc.i was gonna brace then strap but no room(stucco exterior) any ideas??

Pics are attached any help is greatly appreciated-

Steve
      

I have read and searched a bunch on wire size and I wondered if you guys could confirm that #2/0 copper is fine to run from the meter base to the panel.  Upgrading to 200 amp service, 200 amp base and 200 amp panel.  From what I gather its ok for service wires at 200 amps, but in other applications its rated for less.  For what its worth, the poco is running #4/0 to the the meter for the new service.