Power Sags

Lakee911 said:

It's possible that you could provide a another transformer (at your cost) and parallel the utilities transformer.

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Nope. Code does not allow the utility to do that.

The utility also can measure your peak power use on a daily usage.

So all you have to do is increase your power usage for 15 minutes.

But the transformer is not the entire problem.
I am guessing that it is only contributing about 2% of the drop.

Bill Arden said:

Nope. Code does not allow the utility to do that.

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Which code? The utility doesn't follow the NEC. But like I said, "possiblity."

Jason

The voltage drop at startup was about 15 Volts. At 150 Locked Rotor Amps it would take only 0.1 Ohm of resistance to produce a voltage drop of 15 Volts.

#2 Aluminum is 0.32 Ohms per 1000 ft, so a 300 ft round trip would be about 0.1 Ohm.

I have no idea what the resistance of the transformer secondary is but that would also contribute to the voltage drop. Maybe someone here can tell us what it might be.

What are the distance, size, and material of the service conductor?

How much of the voltage drop can be attributed to transformer and service cable resistance?

Bob NH said:

What are the distance, size, and material of the service conductor?

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I think the distance is somewhere around 100'. I'd have to go measure it off for better accuracy. It's really not very far compared to some of the other neighbors.

I wasn't home when they ran the service from the transformer to the house. Being that it's all underground or in conduit, I don't know of an easy (safe) way to verify what is actually there. I'm guessing the power company would have a record of that. However, I wouldn't know for sure if they are just giving me a standard response or if they are telling me what they actually put in.

Also, I don't know if this helps (or if it's just be being crazy), but it seems like sometimes the lights dim really really low and other times they don't do it as bad. So far I can't find a pattern. Lately it seems like it's not as bad as in the past. Maybe I'm just nuts!

jdoll42 said:

Maybe I'm just nuts!

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Accept that as your solution!

Case Closed!

Nate R said:

Accept that as your solution!

Case Closed!

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Now just convince my wife she's crazy too. Good luck!

jdoll42 said:

Now just convince my wife she's crazy too. Good luck!

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Neither you or your wife is crazy the rest of the world is.

Would you mind posting the make and model of the heat pump and a good guess on the footage of buried pipe?

jwelectric said:

Would you mind posting the make and model of the heat pump and a good guess on the footage of buried pipe?

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The heat pump is a GeoComfort GT072TL111CBDSSA.

Of course they updated their manuals to the newer models, so my model number doesn't work against what is currently on their page. However, I did find a "catalog" of theirs with the model number reference page and all of the specs: http://geocomfort.com/Products/Residential_Products/GS_GT_Spec_Mnl_0507.pdf

Basically, it's a 6-ton, upright, top discharge, left return unit.

As to the pipe, there are 6 wells, each 75' deep, so 150' pipe per well. So that's about 900' of pipe, plus all of the connections between wells plus the piping to the house, so probably right at 1000' total is my best guess.

Also, I've got the installer looking into a soft start for this unit. He said they have some that will work with the type of scroll compressor I have, but they've never needed one on a geothermal unit. He is going to contact the manufacturer and see what they say. Hopefully I'll get some good news on that front.

jdoll42 said:

Also, I've got the installer looking into a soft start for this unit. He said they have some that will work with the type of scroll compressor I have, but they've never needed one on a geothermal unit. He is going to contact the manufacturer and see what they say. Hopefully I'll get some good news on that front.

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Update: They installed an additional capacitor to the system. The lights barely blink now. If you are paying attention you can see when the unit kicks on, but otherwise it's hardly noticeable. The installer said he contacted the manufacturer of the heat pump, then ended up contacting the manufacturer of the compressor (Copeland?) directly for the necessary parts.

Needless to say, it's much better now. Thank you all for all of your help and ideas!