Emergency Heat Strips

[Firpo]

Need a little help from my friends. All my life I’ve had nothing but A/C in the summer and a gas furnace for the winter then we move to Oklahoma and I’m introduced to heat pumps. Here’s my issue, before we moved in I had all new HVAC units put in as well as a 22KW whole house generator. Last year during that big freeze a problem arose. When those darn emergency heat strips kick on they draw just about all the power that generator can produce. Right when we needed it the most the generator kicked off due to over-current. Here I am freezing my yayas off trying to troubleshoot the problem, with clamp meter in hand I figured out those stinkin’ emergency strips are drawing close to 82 amperes which leaves only 10A for the rest of the house and that’s just not going to cut it. Had the HVAC tech come out who said about all I can do is disconnect some of the heater strips, say run half of them and I should be okay. Problem is I’m not sure which wire(s) to disconnect. Here’s a couple pictures along with the wiring diagram and if you’d be so kind as to let me know if he was full of beans and if not just which wires do I pull?

 

[KOPBET]

Not questioning your judgement, but if the heater is 80+ amps, why did you get only a 22kw generator?

Be careful. You can kill yourself in there.

I hate heat pumps BTW...

 

[wawazat]

Not questioning your judgement, but if the heater is 80+ amps, why did you get only a 22kw generator?

Be careful. You can kill yourself in there.

I hate heat pumps BTW...

I think at one point 22kw was the biggest they offered before getting into the more commercial biased metal cased units that double in cost. Looks like you can get up to a 24-26kw unit now for under $10k.

EDIT:: The other thing to remember is I believe the branded capacity is on propane. Natural gas reduces the output a little bit.

 

[KOPBET]

This is not electrical advice, but if the CBs can manually disconnect, that would be my choice. CB1 or CB2.

 

[Cowbaby]

To answer your question. see the box on the right side "component arrangement" ?

Take the 2 outside black wires off Htr1 and Htr2 on the top row. then take the corresponding yellow wires off dd1 and dd2 on the other side of the same two strip. You should now have no power wires going to 2 strips and only the 2 center strips are still wired. The black square things are just relays.
But, I am not real sure that is even going to be enough. You may have to kill the breakers that go to your heat strips all together and just run the heat pump part but that isn't going to cut the mustard down in the teens.

Please kill the breaker and take your disconnect block out then test for no power at the wires with you meter first. Be cafeful out there.

 

[CHenry]

I prefer gas heat for this reason. Propane or Natural Gas. My previous house had propane and it was pretty high if ya had to fill a tank in Jan. So I installed a wood pellet stove and would use 2 tons most winters at a cost of less than $600. It would heat the entire house pretty well but I had to use a space heater in the master bathroom.

 

[swampratt]

Some people do not have natural gas or propane.
So those stuck with all electric i would think the heat pump would help the wallet but
an Inverter type may be even better when it gets really cold as it could regulate motor speed.

 

[CHenry]

Some people do not have natural gas or propane.

I get that and thats why I mentioned the wood pellet stove. In a power outage it still runs off a Generator and pulls about as much power as a 100 watt lightbulb.

 

[Firpo]

Not questioning your judgement, but if the heater is 80+ amps, why did you get only a 22kw generator?

Be careful. You can kill yourself in there.

I hate heat pumps BTW...

I guess ‘cuz I didn’t know any better. Like I said, I’d never had any dealings with heat pumps and would have never guessed they could use as much electricity as the entire house I moved from. The HVAC guy said I needed such and such and the electrician said 22KW was as big as it got and would be plenty. Live and learn. The only reason I asked this question is because the HVAC guy made it sound like it was nothing. Reading your responses I’m opting for Plan B am running one of two gas (I have propane) fireplaces in the house and man is it toasty. Just on low it’s keeping the house at 77° and I’m using a ceiling fan to circulate the air. I believe I have a solution. I’ll just shut off the stupid heat pumps and run the fireplace and maybe a couple little plug-in heaters (1500Watt). I should be in good shape. Thank you all for your responses, you were a big help.

 

[dlbleak]

It’s my understanding that a HP is very inefficient at temps below freezing. Wood or resistant heat is a better option for the upcoming front.