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(01-08-2025, 01:27 PM)blackhat Wrote: Are both heat pumps on the generator? If so, are they trying to start simultaneously on the generator? If yes, a 5 minute time delay on power up timer would correct that problem.
Yes both are on the generator, or at least can be. Up till now I turn the breakers off for the upstairs unit if I am on generator power. When we have lost power in the summer I just turn both off. sweating is uncomfortable but you won't freeze to death. its a 10kw unit and is admittedly a bit undersized but a new one is several thousand. it will start the larger downstairs unit but takes a noticeable hit when it does. What I am wondering is if the soft/slow start will ramp it up more slowly.
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(01-08-2025, 01:49 PM)Roly Wrote: Do you have Aux heat on you units ? If my indoor temp drops about 3 degrees below set temp the 15kw aux heat comes on until set temp is reached. Mine is a whole house heat pump if that makes a difference. No gas service near.
Where the lines enter the indoor coil the line in temp is about 130f and outlet line temp is 80 when outdoor temp is 17 or over. Under 17 it drops a little. It was 8 this morning and inlet was 124f at the coil. Roly
yes I have aux heat. the thermostat said it was calling for aux heat, so I dunno.
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01-09-2025, 07:22 PM
(This post was last modified: 01-09-2025, 08:38 PM by crokett™.)
HVAC guy came out this afternoon. As far as the slow start, my unit can't do that. it has to be a more modern unit designed for it. He said something about that kind of unit the power gets changed to DC. They're designed for generators or to be run on battery power. He checked it and the compressor was putting out enough heat, but the aux heat was not working. That's why temps weren't getting past 66 the last 2 days. After some more investigation it turned out the thermostat was connected wrong. It's a Nest. Been there a couple years. It was not hooked up correctly. I'd yell at the installer, but I see him every time I look in a mirror.
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First half of that is somewhere between sort of right and complete bull. Glad he sorted the aux heat problem. You know the answer is a bigger gen set.
Blackhat
Bad experiences come from poor decisions. So do good stories.
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(01-10-2025, 10:20 AM)blackhat Wrote: First half of that is somewhere between sort of right and complete bull. Glad he sorted the aux heat problem. You know the answer is a bigger gen set.
Why? do I have options? I know there's a start cap on the compressor. I know that starting requires a lot more juice than running.
and yes, I know the answer is a bigger gen set, especially since the current one I doubt is big enough for the aux heat so that will have to be disconnected if Im running on the genny. I can't convince my wife to spend the thousands just yet. we've talked about it.
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Options with your existing, no. More modern, kind of, depending. The other stuff about DC and made to run on generators and batteries is drivel.
Blackhat
Bad experiences come from poor decisions. So do good stories.
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I've been thinking about installing a soft starter on our heat pump, just so I could run it on our portable generator if I needed to.
There are several good YouTube videos on the subject. Here is one of the better ones.
https://www.youtube.com/watch?v=MDp1g8r8IVs
Telling a man he has too many tools,
is like telling a woman she has too many shoes.
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(01-14-2025, 04:41 PM)Terry W Wrote: I've been thinking about installing a soft starter on our heat pump, just so I could run it on our portable generator if I needed to.
There are several good YouTube videos on the subject. Here is one of the better ones.
https://www.youtube.com/watch?v=MDp1g8r8IVs
hmm. I Will have to take another look at this. I didn't think there was anything I could do with mine.
