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That's one of them new Nester wireless units. Ties right into the local hotspot and away it goes!

That's not Ohm's Law, that is a trait of constant wattage devices like induction motors driving a constant torque load, IE a compressor or conveyor belt, and SMPS (switched mode power supply) loads. For a compressor when you reduce the voltage the amps do go up until you hit a point where the motor can no longer supply the required torque and it stalls, at which point the amps go up to the locked rotor number till the overload device trips.

For fans and blowers motor power is to the square of the RPM and torque is directly proportional to airflow so with the right style of induction motor if you reduce the voltage you reduce the speed also, this is how the speed taps on a PSC blower motor work, the high tap is the lowest voltage tap of an autotransformer built into the run winding, the low speed is the highest voltage tap, the autotransformer function just intentionally undervolts the motor to make it run slower under load. With no load a PSC fan motor will turn the same speed on all speed taps. Try it some time, with the motor on high measure the voltage from the low tap to neutral.

Note that there are also true 2 speed induction motors for belt drive blowers that start and run as a 4 pole for high but start on 4 pole and switch to 6 pole for low.

IOW a 230v PSC CFM or IDB motor will run on 115 volts, it will just turn slower. A 230V compressor may start on 115v but will stall as soon as pressure starts to build up.

Ohm's Law

Remember that according to Ohm's Law that if voltage goes down, Amps go up. If your unit was rated at 230V and was only given 115V and running, the Amperage drawn was doubled. The motors and compressor were certainly not rated for that amp draw and the product was overheated. That heat would destroy your motors if it weren't for the thermal overloads inside the motors/compressors to protect them. Also remember anytime a safety is tripped, it is weakened. This means that you are lucky the safeties worked. But what the heck is going on around you? Your A/C is a huge liability and nobody should steal power from it's disconnect, as that is against any code. With less than a $40 breaker (most are less than $20) and the same wiring to the equipment, the same voltage can be utilized in a safe manner to the equipment/operator and the HVAC system can remain isolated on it's own circuit as it should always be.

Originally Posted by jnsrose

Lady next door called , her condenser stopped working.

Lol ...

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We had one that we could not turn off the power too, even with the main c/b turned to off. We had to pull the meter and it was still on but that gave us the answer we were looking for, someone hooked it directly to the utility wires before the meter. Free a/c? It was a bank owned, got purchased and they were fixing it up to flip so we don't know who did it. Very dangerous being the wiring was not protected ether.

it's haunted. Obviously.......

Originally Posted by shavedneon

but through my guys off.

through:
[throo]
preposition

In at one end, side, or surface and out at the other: to pass through a tunnel; We drove through Denver without stopping. Sun came through the window.


Threw:

verb (used without object)
to cast, fling, or hurl a missile or the like.

noun
an act or instance of throwing or casting; cast; fling.




I would have done the same thing.

Originally Posted by JWB

you replaced a unit, interesting. hope you replaced the bypassed disconnect.

My thoughts exactly.

It's broke, you need a new one.

Kind of got an answer on this one

The homeowner tied in a piece of equipment in the garage (behind disco), apparentlty the way he double lugged and hooked it up backfed 115v back thru the load side. The homeowner disconnected his contraption and everything worked normal but through my guys off. He was doing something with 3 phase equip. hooked with a 3rd leg generator. I still don't understand exactly what he was doing or why and how. I'll stop by on monday to check on everything and make sure he hasn't tied into our equipment again, maybe get a more thorough understanding.

Lady next door called , her condenser stopped working.

Perpetual motion !
.

you replaced a unit, interesting. hope you replaced the bypassed disconnect.

Or someone hard wired that sucker. Always check for voltage before touching wires. I have found several units like this.

It's pretty obvious. The power doesn't go through those fuses. Either the fuses were bypassed in the disconnect, or that wasn't the disconnect for the unit.

Answer the phone, we got a problem boss !

One of my guys called today, pulled fuses, unit continues to run. I'm not sure what to think, so he sent this picture. I'll talk to him in the morning to see what he eventually found with it, unit got changed out anyway.