House power from RV generator as back-up

I want to thank Mikeh, Volkeman, and Donc and others for sharing their experience and talent in answering my question correctly in regarding the most important part of the question: to SAFELY supply power from the RV. Electricity is very simply quite complicated, and can kill you.

I don't know how many readers of this forum have looked closely at Jim Godfrey's profile picture, but I have to wonder how he obtained that photo of me as a child....

Be safe out there and seek happiness not only on the Holidays!

Dougn

I don't know how many readers of this forum have looked closely at Jim Godfrey's profile picture, but I have to wonder how he obtained that photo of me as a child....



Dougn

   And how well it fits this thread....

So our first thanksgiving dinner in our first house (1983 I think).  Drywall is on but not taped.  No covers on the outlets.  Not all wiring circuits hooked up.  A million other safety issues.  But we had a house and no mortgage.  It would take 7 more years to finish.

But anyway, Thanksgiving dinner and my wife is doing dinner for both our parents for the first time.  We sit down to eat and #1 son (5 at the time I think) did exactly what is shown in that picture.  All lights in the house go out.  Screaming kid running around in the dark.  No one can move because its pitch dark.  No cell phones for flashlights in those days.  I feel my way along the wall, out of the dining room, through the kitchen to the basement stairs, down the stairs and into the basement, along the wall to the breaker panel and find the breaker by feel.

I was informed that the rest of the wiring would be completed tomorrow or I would be living elsewhere.  For some reason my parents in law insisted that covers be put on the receptacles right away too.

Well, I think everything that can be said on this subject has been except one:

The quickest way to ruin a $2,000 fridge is to run it on a small generator that barely makes enough amperage to handle the load.  I learned this the hard way years ago, on my first hurricane after we moved to Houston.  I had previously picked up a small generator at Northern Tool that I calculated should have been capable of keeping my fridge and freezer running, plus a fan, a TV, and a lamp.  Every time the fridge or freezer would kick on, the generator would bog down, obviously working hard to keep up with the load.  In order to stretch our gasoline supply, we'd shut everything off every four hours, and over night.  About a week in, the fridge just quit coming on.  At that point, we threw in the towel, gave all the meat to the neighbors, and moved in with our San Antonio kids for the duration.  The repair bill was about $500 -- more than I paid for the generator.

After that experience, about the only thing I'd try to run off that cranky ONAN in the RV would be the stuff in the RV.  If all I had to keep my house from freezing was that generator, I think I'd drain the water lines in the house and move into the RV.

Making a plan for a power outage is important I think.  Sometimes we worry about things that don't matter, sometimes we forget things that are.  But you also need to think about how long an outage you are preparing for and adapt the plan.

1-2 hours: probably not an issue in most homes.  Grab a book and snuggle up.

4-8 hours: keeping the house warm enough to be comfortable and not freeze pipes is the priority.  Keep power to the furnace, don't worry about anything else.

8 hours plus: Most modern refrigerators / freezers will last close to 8 hours.  The new freezer we got states if not opened it will hold temp for 48 hours.  After 6 hours though I would start worrying about the refrigerator and freezer.  They do not need to run all the time, just long enough to get back to temperature.  Here is where a wireless temperature gauge comes in handy so you do not have to open them up to check.  I have one on the desk in my office with sensors in each freezer compartment.  I can tell at a glance what the temp is and if there is a problem.

Run an extension cord from the generator to each appliance then alternate on until temperature is reached then off for 4 hours or so.  Or as long as its comfortable for the furnace.  Try very hard not to run anything else when the furnace is on if you have forced air.  The fan motor starting will pull the voltage down enough to harm other things if the generator power is marginal.  Which it will be if using the generator on the PC.

For lights get a couple LED lanterns.  They run on 4 - 6 D cells and will last days if not weeks.  We used to keep 2 oil lanterns ready when we were in Oregon but when the LED ones came out we bought 2 and got rid of the oil ones.

If you have a gas hot water tank and are handy rig it up the same as the furnace, wired to a receptacle that you can then unplug and plug it into an extension cord.  NOTE this will not work on electric hot water tanks, only the gas ones where the only power needed is for the controls.

We never had backup power in Maryland. I found a tip somewhere to know when to throw out the meat in the freezer. NOW while you have power, make ice cubes. Put some in a freezer container and stick it in the middle of the freezer. Check after power outage or trip away from home. If still cubes, good to go. If melted or refrozen as ice puddle, start tossing.

We never had backup power in Maryland. I found a tip somewhere to know when to throw out the meat in the freezer. NOW while you have power, make ice cubes. Put some in a freezer container and stick it in the middle of the freezer. Check after power outage or trip away from home. If still cubes, good to go. If melted or refrozen as ice puddle, start tossing.

GREAT advice!  There is so much here. What a thread!   We use a variation for freezer monitoring. I freeze water in a small plastic cup, and put a penny on top, If the penny is sunk in or on the bottom, you know thawing happened.

As a follow-up, I had an electrician evaluate my concept, and glad I did. He loved the idea. It was not real complicated, but easily over my pea-brain saw-dust fogged head. He added a GFCI, code for a garage outlet. He also had concerns over the difference in type of ground between home and RV, but it seems to not be an issue.  Best of all , he did a clean code-compliant install in a tenth of the time I could have.

I went the simple route I had envisioned, an appliance plug-in from boiler to outlet, easy to swap to extension cord from the RV for generator supplied power for the boiler when needed.

I tested it and it works great off of the generator, but discovered it draws closer to 10 amps with the 50 extension cord, about twice what I had estimated, but still not too much. The zone controller itself pulls almost 4 amps just static.

As long as we are at home when the power goes out....

draws closer to 10 amps with the 50 extension cord

Check the gauge on the extension cord.  Smaller gauge cords will heat up and as they heat the resistance increases.  On short runs or intermittent use that rarely matters.  But continuous use over 50 feet, it can be a factor.

Good quality 12 gauge cords are crazy expensive right now but that's what I would use in this situation.  Per spec a 14 gauge cord can carry 15 amps but over a large run and continuous use that should be derated putting you close to maximum.  A 12 gauge cord can carry 20 amps so even derated you have a comfortable margin.

If you already have a 12 gauge, then never mind...........

Good quality 12 gauge cords are crazy expensive right now but that's what I would use in this situation.  Per spec a 14 gauge cord can carry 15 amps but over a large run and continuous use that should be derated putting you close to maximum.  A 12 gauge cord can carry 20 amps so even derated you have a comfortable margin.

Sound Advise!

I have two 25 foot long RV 30amp extension cords that I carry in our PC "just-in-case" the power peg is so far away as was the case in Badlands National Park.  RV 30amp cords make excellent high-power extension cords for repurposing at home.  You only need the appropriate adapters which are nice to carry in your PC as well.

So buy what you need for your PC and repurpose them at home for the rare power outage.

Ron , I carry one 25’ RV extension but two? The post at the park you mentioned was 75’ away? What were they thinking

The power peg was far.  It has been many years since camping in that camp ground.  I wonder if we were camped in a non-electric site, but near an electric one.  If memory serves me correctly, there was nobody else camping in the entire camp ground at the time.  We generally seek a nice view when picking a campsite so I assume that is why we didn't pick an electric site to begin with.  It has been too long to remember enough detail.

Ron, in any event we’ve found having one Rv ext cord had come in handy more than once. I also carry a 10-12 foot old section of 3/4” garden hose. There’s been times where once parked the sewer connection was a few feet beyond our reach.

Now folks we return you to your regularly Scheduled subject.  😁

Apologies if this has been covered, and I missed it.  All Onan generators lose output capacity with altitude.   The Onan 4000w generator is producing ~3300w at 5500'.  Then ~140w loss for every additional 1000'. As was noted by others, a heavier gauge extension cord is a requirement for providing an electrical output any distance from your rig.
Safe travles.

- CD