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Tankless water heaters

geochurchi

Senior Member
Location
Concord,NH
Occupation
Retired electrician
Hi All, aside from following mfg. requirements, what does the code require for the installation, what code article covers this?
 

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
An electrical tankless, like a resistance heating element for a full house heat pump, may require multiple high amperage 240V circuits to develop the needed wattage. That will be part of the mfg. requirements, along with an EGC connection (bonding.) The Code does not really add anything to that.
Use those figures to calculate demand loads upstream (non-continuous) and follow the Code for those.
 

kwired

Electron manager
Location
NE Nebraska
Occupation
EC
Hi All, aside from following mfg. requirements, what does the code require for the installation, what code article covers this?

Art 422 Appliances.

Though there really is nothing in there for this specific appliance, but you still need to follow all general rules for appliances as well as other chapter 1-4 rules in particular selecting minimum conductor ampacity and max overcurrent protection.
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
Also there is no 125% requirement as there would be with up to 120 gallon storage type hot water heaters.
 
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