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muckwire
Jan 14, 2007, 12:43 PM
Join Date: Oct 2006
Posts: 3


Seisco water heater install

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This is a question for both an HVAC installer and an electrician.

I have and (sic) electrician who has done the regular type of rural wiring from the transformer on the road to the potheads on the house and to the panel but and I say but I want to know what should be done correctly to make sure I get the safest and correct installation.. I am in the bush in a less developed area on an island, two dogs, five donkeys and a lot of ocean and need help with the installation of a Seisco tankless electric hot water heater. Electricity costs are a @#... so running a regular hot water tank is nuts.

I have a panel large enough and 120 or 240 power available. My water pumps are 240. Power outages are regular occurrences
I have a Seisco model # sh/ra- 14
V-240
A 29.2
KW 7
Hz 50/60

A large panel, a sub panel with space for two breakers and a knock off switch,

QUESTION:
1) what gauge wire do I use from the panel to the sub panel, and

2)what gauge wire doe I use from the sub panel to the seisco unit, the seisco unit has two wires with clamps/connectors for hookup.

3)what size breakers (double pole) 20 or 30?

I am using kitec piping (canadian tire brand) to the existing hot water line.
Copper 3/4 inch out take from the seisco to connect to the existing hot water house supply which is 1/2 pvc with
Copper 3/4 inch cold water intake on the seisco unit hooked into an available 3/4 pvc cold water supply, cold water is 70 - 90 degrees before heating
I have pvc and cpvc fittings with shark bite connectors. Connectors are copper to pvc/cpvc, and pvc to pvc The piping is not the problem, the electrical is.

I could really use some specific information so that I can make sure the electrician does this right.

My donkeys would appreciate your help. Next step solar.

tkrussell
Jan 14, 2007, 01:30 PM
V-240
A 29.2
kW 7
Hz 50/60

QUESTION:
1) what gauge wire do I use from the panel to the sub panel, and

2)what gauge wire doe I use from the sub panel to the seisco unit, the seisco unit has two wires with clamps/connectors for hookup.

3)what size breakers (double pole) 20 or 30?

All can help with is with the electrical questions. I will send a copy of this over to the Plumbing Forum in the event you have not done so already.

1. If the subpanel is only for the water heater, then see answer #2, if there are other loads to be fed by the subpanel, then I cannot answer fully, as I do not know what those loads are.

2.A 7KW 29.2 Amp load at 240 volts will require a # 8 copper wire, if subjected to the similar codes used in the USA.

3. Use a 2 pole 40 amp circuit breaker.