Tankless water heater No Neutral?


Old 10-02-09, 06:13 AM
Thread Starter
Join Date: Oct 2009
Location: Maine
Posts: 1
Received 0 Votes on 0 Posts

I as well am wiring an AE125 unit. Im a little concerned about the wiring schematic I have. So the way I understand it we need 3 220/240 lines from the breakers to the box. So thats 6 Live wires connected to this machine Directly from breaker to unit. 3 grounds from the breaker boxs ground bar, to the ground screw in the unit. But no Neutrals?

Is there no Neutral? Ive never heard of an electrical device operating without a neutral.

Can u generally recomend this product? Does it function well and efficiently for a home?
Sponsored Links
Old 10-02-09, 06:53 AM
pcboss's Avatar
Forum Topic Moderator
Join Date: Jul 2002
Location: Maryland
Posts: 14,901
Received 23 Votes on 19 Posts
A straight 240 volt appliance like and air conditioner compressor, water heater etc do not require a neutral.

Units like a dryer or stove can have 120 volt loads like for timers and lights and require a 120/240 volt circuit with a neutral.

Have you performer a demand load calculation to see if your service can handle the load your tankless heater will demand? Often times a service upgrade, or an additional service is required. This will add thousands of dollars in additional cost to adding the unit.
Old 10-02-09, 07:10 AM
ray2047's Avatar
Group Moderator
Join Date: Mar 2006
Location: USA
Posts: 33,597
Received 13 Votes on 11 Posts
Six leads would indicate three 60amp feeds. Most newer home services are only 200a older ones are only 100a. As PCboss has said you need to check your service size. It won't work on an older 100 amp service and may not work on a 200a service if you have an electric dryer, electric stove, AC, and electric heat or heat pump.
Old 10-03-09, 08:19 PM
Join Date: Mar 2006
Location: NE Wis / Paris France{ In France for now }
Posts: 4,808
Received 0 Votes on 0 Posts
That tankless electric waterheater that is 26 KW { 26,000 watts } it may sqeak by with 200 amp service but if you have 100 amp service forget it you will trip the main breaker if you have anything else in the house is on it will trip no question asked due it about 108 amp total current drawage { that on 240 volt 208 volts will be slightly lower amparage }

Alot of my customer were not too pleased with the performace with it to slove it I suggest the customers to upgrade the service to 320A class { 400 A resdentail service } which it will have two 200 amp main breaker boxs one for main house useage and the second box for tankless waterheater useage and it is not cheap but much cheaper than a true 400 amp service.

The other thing that many POCO is getting strict with this set up due they allready dealt with few burned out transfomer from overloading from tankless waterheater.


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

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

Thread Tools
Search this Thread
Display Modes
Ask a Question
Question Title:
Your question will be posted in: