DIY Home Improvement Forum banner
1 - 13 of 13 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter · #1 ·
I purchased my townhouse in 2008 and in 2010 the water heater started leaking. I had it replaced with a tankless water heater and had an independent guy do the install. He ran new wiring accross the ceiling (above it) to the breaker. No permits were pulled at that time. No issues with it for the past 12 yrs. Anyway, I am having to re-pipe my townhouse now due to pin hole leaks in the piping and the company told me that the city will require an additional electrical permit for the water heater since it is not the original. Said an electrician may need to bring the electrical connection to code. My questions is, Can an electrican come out to make sure it is up to code and if it is, give me something in writing? How does that really work. What exactly is the city going to inspect as far as the wiring if I am only having the pipes replaced? Do they plan to open up the Breaker to look at the wiring?
 

·
Registered
Joined
·
633 Posts
The city has to approve the electrical to the heater in it's entirety.
I am surprised the townhouse had an adequate service since it was not built with a tankless originally.
 

·
Registered
Joined
·
633 Posts
It may be a gas heater. I just assumed electric after mentioning running wiring and electrician. If a gas, that usually requires a bigger gas line than a tank type heater.
 

·
Naildriver
Joined
·
17,671 Posts
Yeah, different scenario. You have an electrical hog. Probably takes 80 or more amps to run it. The wiring is pretty large and I would expect an inspection to rule. You will most likely be required to pull a permit, hire an electrician to check the wiring and breakers and sign off on it, to allow the municipality the opportunity to pass the permit.
 

·
Registered
Joined
·
5,978 Posts
A modest tankless takes 75 amps. Serious whole house tankless can draw 150 or even 180 amps. You need to start with a Load Calculation for your house. Those are surprisingly simple, you need

  • the square footage (this will be for a "catch-all" that covers almost all lights and 120V plug-in loads)
  • number of kitchen receptacle CIRCUITS ("2 or 3" is a correct answer, "8 receptacles" is a wrong answer and a waste of your time).
  • number of laundry room ditto ditto ditto (usually 0 or 1)
  • nameplate amps, VA or watts off of all 240V appliances and fixed-in-place 120V high-draw appliances:

The last one means built-in microwave, bathroom heater, dishwasher, disposal, central vac, furnace. NOT refrigerators or fans, they don't draw enough to matter). All are converted to VA (volt-amps). For resistive heaters, watts equals VA. if it specified amps, multiply its stated amps x its stated volts (e.g. 10 x 230 = 2300). Dryers are counted as 5500W unless you know them to be something else.

You don't just add them, they go through a worksheet. This does some "fudge factors" to account for the fact that they won't be all maxed out at once, e.g. reduces the electric oven/range number to reflect practical usage (not all burners are cycled on at once).

You also cross off any loads that won't run at the same time, using only the higher figure. (e.g. electric resistive heat vs. A/C unit. However, the air conditioner probably uses the furnace's air handler, and the air handler is like 95% of gas furnace power.
 
1 - 13 of 13 Posts
Top