Old house from 1930s

[WorldwideDave]

House in USA I am planning system for has an old panel in it. My guess is a 100 amp panel. House built in 1930s. Remodeled in the late 60s. If I add the breakers together, there is 120 amps of breakers plus a service disconnect 240v/100 amp breaker.

There is one 240v / 30 amp load. It is for the pool pump. Does that mean it could surge to 7200 watts on that circuit?

I am trying to multiply volts x max amps of each breaker to figure out maximum usage potential of the service panel.

For that pool circuit it has a gas heater and a variable speed pump.

The rest of the circuits on the panel are all 120v. Some 15a and some 20a for lights and outlets.

Considering doing a split phase inverter for just pool and a single phase (?) for rest of house.

 

[time2roll]

VSP is not going to have any real surge. Generally they ramp up moderately. Check the actual rating but 15 or 20 amp circuit might be plenty for the pool depending on other equipment. My Pentair has a wattage display right on the pump.

afaik a 100a panel can be fed with a 20 amp breaker as an additional solar feed in.

 

[WorldwideDave]

My pool pump is 2400 watts max, 240v. Does that mean 10 amp breaker would work for that? In my panel the pool equipment- pump and gas heater - has two 15 amp breakers connected. Does this mean 30 amp or 15 amp circuit for pool? Think it means 15, but 240 circuit.

 

[time2roll]

Technically 10 amps can be drawn (240v) so really a 15 amp breaker is needed. This is considered a 15 amp circuit as there will never be more than 15 amps in any of the wires. Gas heater should be very small draw for the electronic controls. Incandescent pool lights could add significant load on one side as they are often 300 to 500 watts (120v). Easy to set the pump at lower power draw.

The 240v circuit should have a combined breaker where both trip together.

 

[WorldwideDave]

The 240 is a combined breaker. Old school where it is two of them next to each other with a nail or something rusty between the two of them. 15 amps each breaker, though as you said 10 amps can be drawn. And thank you for explaining that it is 15 amp circuit even though there are 2 breakers. My guess is that now a days when you buy a 15 amp 240 breaker, you just get one larger breaker that covers both lugs/connectors at the panel with just ONE switch, vs two separate breakers. I think I am right?

The pool light I think was upgraded to LED. Seems super bright compared to what it was. Sorry I cannot remember. I know they added a new GFCI or similar breaker in the panel - strange that it was not there before, am I right?

I was out of the country when pool was being redone/surfaced/upgraded.