Portable Generators & Furnace/Heatpump

[Midasknight]

This spring I'll have a new electric furnace and heatpump installed. Because of this last weeks weather and power outage (lucky only two days here in Canby) Is it possible to connect a portable generator to this combo? If so, would I have the team that's installing the new furnace / heatpump install it in a way that I can use a portable generator to plug into this? The home is only 1272 sq ft.

Also, can a plug in be installed somehow to the electrical system of the home so I can use this portable generator to run power to the whole home? Never had a generator before so I don't have any idea what size of generator to get and I have no idea how a generator can power heat and electricity to the home. Can you only run power to just a few items in the home like the refrigerator or freezer?

Thank for any information. First time home owner (Aug 2020)

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[Alexx1401]

Yes you can have a transfer switch installed so you can just plug the generator in and flip a switch to power the home and prevent the power you are generating being fed back out. Only thing you need to decide is how much power you want. If you want to run the heat pump you would just need to find out how much wattage it needs and go from there. Of course what is the budget? Most will look at how often they lose power and for how long, vs, how much do they want to spend. We go some years and never lose power. Worst I have ever seen in one time it was like 30 hours. So I keep a generator that runs off LP gas that will run 6K watts. That is plenty to keep the fridge and freezer, some lights and TV on. Since we have gas at the current home we can use the gas fireplace if power is out. Could even hook up the furnace if I needed too. So place to start it look at cost, see what you want to spend. The nicest is of course the genset that is set to start on it's own and run when you lose power. These are normally Diesel or gas powered and of course the most pricey option.

 

[BBQ Guy]

Transfer switch.
My neighbor across the street uses a setup like your asking about. He has a 5400 watt generator. It operates everything in their home except the dryer.
Review your needs and wants then size accordingly.
I'm contemplating a similar setup. We lose 3-4 times a year. At any given time. The most worrisome was a few years ago during one of our 90° plus stretches of weather in August.
I don't want an auto genset. They are expensive. Costly to install and maintain.

 

[bigbearbear]

When you're looking at the generators, be sure to also check how long can they operate continuously before you need to shut them down. Most of them cannot run continuously for many days, and if 2 days is the max length of time for outages, you can base your purchase for a generator that can run that long. Also note the service requirements so you'll need a stock of air filters and engine oil on hand. I've read some forum posts about generator owners who took out their generators only to find that it won't work due to neglect.

An alternative would be solar panel with Tesla Powerwall, which is what I have. This is more expensive but once you install it, you can forget it and it'll work transparently in the background. When an outage happens, you won't even notice it unless you look at the Tesla app on your phone which will warn you about the outage and you might want to power down certain things to conserve the battery power on the Powerwall. You'll get 26% of your purchase price back as tax investment credit if you install this year.

 

[BBQ Guy]

When you're looking at the generators, be sure to also check how long can they operate continuously before you need to shut them down. Most of them cannot run continuously for many days, and if 2 days is the max length of time for outages, you can base your purchase for a generator that can run that long. Also note the service requirements so you'll need a stock of air filters and engine oil on hand. I've read some forum posts about generator owners who took out their generators only to find that it won't work due to neglect.

An alternative would be solar panel with Tesla Powerwall, which is what I have. This is more expensive but once you install it, you can forget it and it'll work transparently in the background. When an outage happens, you won't even notice it unless you look at the Tesla app on your phone which will warn you about the outage and you might want to power down certain things to conserve the battery power on the Powerwall. You'll get 26% of your purchase price back as tax investment credit if you install this year.

I saw you mention your set up in other threads.
Even with our somewhat frequent outages where I live, it just doesn't pencil out financially.
It is cool technology though.

 

[The Heretic]

You will need a substantial sized (KW) generator to power a heat pump:

Air conditioning and heat pump loads on a generator

Chart showing how many kw and amp an air conditioner & heat pump uses. Air conditioning and heat pump loads on a generator.

www.generatorjoe.net

Look at the size of your heat pump (in tons/BTUs) then look across the columns to see how many starting amps are required under the 240V column (most likely voltage used). Multiply the amps by the volts to get the KW required to start the heat pump alone. It can easily be 15-20 KW or more. This is not a KW rating you will find in most portable/transportable gensets - which are usually less than 10KW and top out at about 12KW.

That is just to start the heat pump alone. You will need another 10KW or so to run the rest of the house - 5 KW at least. Most people have a 200 amp service to their house these days, which means, theoretically, that up to 48 KW could be used to power the house but most do not use all of that power.

Note that I mention that this is the power needed to start the heat pump. Heat pumps have a good sized electric motor in them to run the pump. Starting wattage is often easily more than 2-3X the wattage needed to run the pump once it is started. Same is true of other items that have motors in them - furnaces, freezers, refrigerators, washers and dryers. Other large consumers of power are electric stoves and water heaters.

Assuming you use PGE you can get some clues from their website as to how much power you use day to day - they have tables showing your hourly, daily and monthly power usage. Looking at mine, I can see when I turn on my 10KW electric furnace I use up to 10KW when I turn on the heat in the morning when it was pretty cold about 10 days ago. I have a woodstove for backup heat, so I do not use the furnace during a power outage - I do not have a genset large enough to power it.

 

[Certaindeaf]

This spring I'll have a new electric furnace and heatpump installed. Because of this last weeks weather and power outage (lucky only two days here in Canby) Is it possible to connect a portable generator to this combo? If so, would I have the team that's installing the new furnace / heatpump install it in a way that I can use a portable generator to plug into this? The home is only 1272 sq ft.

Also, can a plug in be installed somehow to the electrical system of the home so I can use this portable generator to run power to the whole home? Never had a generator before so I don't have any idea what size of generator to get and I have no idea how a generator can power heat and electricity to the home. Can you only run power to just a few items in the home like the refrigerator or freezer?

Thank for any information. First time home owner (Aug 2020)

This is why the jesus invented 1500 watt ceramic space heaters.. that sell for $20. A good $500 generator should be able to run the fridge and that.

 

[The Heretic]

This is why the jesus invented 1500 watt ceramic space heaters.. that sell for $20. A good $500 generator should be able to run the fridge and that.

Mine kept my office warm, but it was only about enough to keep one room warm, which was ok.

The last day the power was out I got tired of the whole house being below 60* so I started a fire in the woodstove and then the power came back on.

 

[Certaindeaf]

Mine kept my office warm, but it was only about enough to keep one room warm, which was ok.

The last day the power was out I got tired of the whole house being below 60* so I started a fire in the woodstove and then the power came back on.

I hear you. I certainly defer to you all things electric etc. but I just fixated on his smallish house and a simple way to look at the issue.

 

[The Heretic]

I hear you. I certainly defer to you all things electric etc. but I just fixated on his smallish house and a simple way to look at the issue.

I missed the part about the size of the house.

My office is about 150 SF so it is small, but I leave the door open and it has a high ceiling (about 12') so the heat from that heater was leaking out. I had that heater in my living room which is about twice the size of my office and completely open to my other living room and somewhat the kitchen and dining room. It did warm up the living room to make it tolerable.

But the ceiling fans were not running in any of the rooms so the heat was not spreading. I wasn't in danger of freezing as the temps inside the house were in the upper 50s, I just prefer the temps to be about 60* at least and preferably about 62-63*.

 

[Flopsweat]

I have a fireplace and the power outages of any note have been in the winter, so my screen/storm door has served well as a refrigerator. And I have a BBQ out back. Since all I have to power is lights, router and computers, my generator is a 1500W portable with a long extension cord. The added plus is that I'm able to loan it out when nearby friends have no power but I do.

 

[cigars]

I picked up this Generac about a month ago. We only really have a regular fridge and a small fridge to keep powered so it meets our needs, plus it's super quiet. Costco just dropped their price to $899 on it (of course). You have to log in to see the member price.
Generac 3000W Running / 3500W Peak Electric Start Carb Compliant Inverter Generator (costco.com)

Today I ordered this to compliment it.
Duracell PowerSource 660 (costco.com)
$499. Home Depot is asking $699.

 

[Midasknight]

Thank you all for all this information Lots to absorb here. Not knowing about how much the heatpump starting up plus run time makes me think in terms of getting a generator running lines into the home to power: Refrigerator / Freezer / some lights / and I like the idea in this case of adding some ceramic space heaters. My place is standard ranch and no vaulted ceilings. Very level place. So heaters for two bedrooms and maybe two heaters for the front room. I have just a regular fireplace BTW.

So for my place @ under 1300 sq ft ... running items mentioned above ...What would people here recommend on these portable generators? Watts size?

Another question: I'm wanting to add a fireplace insert. I suppose for firewood? or pellet's?

Thanks all !

 

[The Heretic]

Thank you all for all this information Lots to absorb here. Not knowing about how much the heatpump starting up plus run time makes me think in terms of getting a generator running lines into the home to power: Refrigerator / Freezer / some lights / and I like the idea in this case of adding some ceramic space heaters. My place is standard ranch and no vaulted ceilings. Very level place. So heaters for two bedrooms and maybe two heaters for the front room. I have just a regular fireplace BTW.

So for my place @ under 1300 sq ft ... running items mentioned above ...What would people here recommend on these portable generators? Watts size?

Another question: I'm wanting to add a fireplace insert. I suppose for firewood? or pellet's?

Thanks all !

The heaters will take about 1.5 to 2 KW each, when turned on high. I have one that takes that kind of power.

You either want ones with a fan in them or an external fan, to move the heated air around. I have ceiling fans that do that job well, but they are not powered with my genset which I use with extension cords - for now.

So four heaters would be about 6-8KW just by themselves.

Lighting - it depends on what kind of lights you have. I have mostly LEDs everywhere, some CFs. I don't even bother to bring them into the calculation as they use 100-200 watts only altogether.

A fridge would be the next thing. Think about 250 watts, with about 1KW starting for newer fridges, more for older ones. A chest freezer will last longer, but consume about the same power depending on the size, especially if you keep it closed. Mine (full) lasted about 3 days before things (mostly just ice) on top started melting.

I have external temp indicators I bought for the freezer and fridge that have a wired probe. They stick to the outside and the wire is thing to go inside past the door seal. The idea is you know what the inside temp is without having to open the door and let the heat in and the cold out. They last for several years and are cheap.

There is only one pellet stove that I know of that doesn't require power.

 

[Alexx1401]

Thank you all for all this information Lots to absorb here. Not knowing about how much the heatpump starting up plus run time makes me think in terms of getting a generator running lines into the home to power: Refrigerator / Freezer / some lights / and I like the idea in this case of adding some ceramic space heaters. My place is standard ranch and no vaulted ceilings. Very level place. So heaters for two bedrooms and maybe two heaters for the front room. I have just a regular fireplace BTW.

So for my place @ under 1300 sq ft ... running items mentioned above ...What would people here recommend on these portable generators? Watts size?

Another question: I'm wanting to add a fireplace insert. I suppose for firewood? or pellet's?

Thanks all !

How often do you expect to loose power where you are at? If you are in the major metro type area chances are it will be seldom and if it happens not for long. Again it all comes down to cost. Honda seem to be the one others are judged on. They are pricey but they of course are nice. Another is fuel. One that runs on gasoline means you have to store and rotate the gas for them. It's why I finally went to one that used LP gas. The gas can be easily and safely stored and does not go bad. The little bottles like used for most BBQ's seem to be sold everywhere. So even if there is a bad storm with lots of power out chances are you can still buy more if needed. The one I bought in a 6K running watts, electric start or manual. Was about $600 from Home Depot. Even the manual is easy to do, no harder than starting a lawn mower. Bought a few heavy duty, 12/3 50 ft cords to go with them. Run the cords into the house then more cords off them. 6K will run a lot. Having a fireplace as long as you keep fuel for it you will be fine. Never had an insert so know nothing about that. Whichever you pick again just make sure you keep some of either the pellets or wood on hand in case you need it. Some of the Honda ones are 3 or 4 times as much but some are so quiet that you could sleep with it running. Mine is not annoying loud but nothing like some of the Honda ones I have heard.

 

[osprey]

I have a smallish house 1200 sq ft or so and have gone the better part of of a week with no power on several occasions. I have found a honda 2000 watt generator will run the fridge, two freezers, all the lights, tv and gas range/stove110v control power. I am lucky to have natural gas heat and cooking so very little electricity is needed to keep warm and cook. The startup amperage of a heat pump would require a very large/expensive generator, so I would recommend installing some sort of wood burning or propane heat for power outages. If available Natural gas is even better.

 

[Provincial]

I recall seeing heat pumps that used a Variable Frequency Drive to vary their output. This was for energy savings when the full capacity of the system wasn't necessary for heating/cooling. The side benefit was that the VFD had a built-in soft start function that ramped up the motor slowly, which greatly reduced the starting current flow.

Just something to consider if buying a new unit.

 

[BBQ Guy]

I recall seeing heat pumps that used a Variable Frequency Drive to vary their output. This was for energy savings when the full capacity of the system wasn't necessary for heating/cooling. The side benefit was that the VFD had a built-in soft start function that ramped up the motor slowly, which greatly reduced the starting current flow.

Just something to consider if buying a new unit.

That would be pretty sweet.

 

[Flopsweat]

I have a couple of spare UPSs that need battery replacement. Since they use small 12 volt batteries I'm thinking of replacing them with large (car/boat size) sealed deep cycle batteries to extend their runtime. I know the chargers in them are not made for batteries that size, so I'm planning on putting in a switch and terminals so I can charge it with a car charger or a car. The internals can probably handle the trickle charge after that. If I can get a few hours of silent backup power I won't need the generator for most of the outages that we get. It's cheap and loud, so this could be a plus. And it'll be a fun project.

 

[The Heretic]

I have a couple of spare UPSs that need battery replacement. Since they use small 12 volt batteries I'm thinking of replacing them with large (car/boat size) sealed deep cycle batteries to extend their runtime. I know the chargers in them are not made for batteries that size, so I'm planning on putting in a switch and terminals so I can charge it with a car charger or a car. The internals can probably handle the trickle charge after that. If I can get a few hours of silent backup power I won't need the generator for most of the outages that we get. It's cheap and loud, so this could be a plus. And it'll be a fun project.

You probably don't want lead acid batteries inside the house. Prefer lithium ion if the charger will work with them, AGM if not?

I got a 1500 VA UPS that will run my router and antenna for about 10 hours, and the whole office setup for about an hour. Then there is the laptop which run about 5-10 hours depending on what I am doing.

I now have three LP 20# tanks. The genset is supposed to run 10-12 hours on each at 50% load. If I don't need to be doing consulting/contract work, and I have firewood, I can get by with running the genset for about 4 hours a day at 50% load - 2 in the morning, 2 before it gets dark charging everything and running the fridge, maybe an hour or two every other day for the freezer.

Went into town today, saw a LOT of trees and limbs down going down the mountain.

Listened to a guy on the radio who does consulting work for power outages and repairs and so on. He said two things; 1) we need to do a better job of dealing with trees. 2) We need to put lines underground whenever possible (when opening up the ground/roads for repair/etc.) - he said the main cost for underground was when the ground is dug up.