# Combining two Propane tanks for generator



## PatD (Sep 15, 2020)

I have a 500 gallon propane tank for the household appliances and another 500 gallon tank for the generator. During hurricane IDA my generator propane tank went from 80% to 50% before the power came back on. I could not reach the propane company for a refill and still have not received a refill on the generator propane tank. The propane company is overloaded, naturally.
My question is: can I connect my house propane tank to feed my generator propane tank if I am running too low on the generator tank? Is this allowed by the NFPA code and the local (Louisiana) plumbing code? I know it would have to be done by a licensed plumber. My two tanks are about 65' apart.
Thanks in advance
Pat in Covington, LA


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## oldcodger (Sep 13, 2021)

PatD said:


> I have a 500 gallon propane tank for the household appliances and another 500 gallon tank for the generator. During hurricane IDA my generator propane tank went from 80% to 50% before the power came back on. I could not reach the propane company for a refill and still have not received a refill on the generator propane tank. The propane company is overloaded, naturally.
> My question is: can I connect my house propane tank to feed my generator propane tank if I am running too low on the generator tank? Is this allowed by the NFPA code and the local (Louisiana) plumbing code? I know it would have to be done by a licensed plumber. My two tanks are about 65' apart.
> Thanks in advance
> Pat in Covington, LA


Sure you can cross pipe two tanks. You would need a valve installed between the two tanks so that you could control which tank you feed the generator from.


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## tabora (Sep 6, 2018)

I have an old Fisher R966 sequential regulator/manifold at my island cottage. You connect 2 tanks and then they are used in sequence. When the "first" tank empties and the pressure drops to near zero, the second tank automatically starts feeding. That way, we can call and have them replace/fill the first tank while the second is in use. I like this more modern one:









*  Flame King 2-Stage Auto Changeover LP Propane Gas Regulator-ACR6 - The Home Depot  *
The Auto-Changeover LP Regulator allows you to hook up 2 Propane tanks and the regulator


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## PatD (Sep 15, 2020)

Can this valve handle the flow rate of my 25kw generator or is it just for RV stoves, heaters, etc.? My generator uses up to 315,000 BTU/hr.
In reading the literature and FAQ on the Home Depot site, this will only handle up to 190,000 BTU/hr. I would prefer to have a manual valve that
would feed the Generator tank from the house tank in order to keep the generator tank from going too low. I only use the house tank for hot water heaters, clothes dryer and very seldom stove top. The house tank is buried and the generator tank is above ground.


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## iowagold (Jan 22, 2020)

PatD said:


> Can this valve handle the flow rate of my 25kw generator or is it just for RV stoves, heaters, etc.? My generator uses up to 315,000 BTU/hr.
> In reading the literature and FAQ on the Home Depot site, this will only handle up to 190,000 BTU/hr. I would prefer to have a manual valve that
> would feed the Generator tank from the house tank in order to keep the generator tank from going too low. I only use the house tank for hot water heaters, clothes dryer and very seldom stove top. The house tank is buried and the generator tank is above ground.


*sorry late to the party.
lol
yea you need a large volume tank switch.
check in with the LP service guys in your area to see if they have this feature available.
try rego products 7525b series*
*click here for the rego pdf on the 2 tank switches 400k and 450k btu*

*that setup might work for your setup.
they also work for the 100 lb tanks for construction sites.*

pm me if you need links


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## PatD (Sep 15, 2020)

iowagold said:


> *sorry late to the party.
> lol
> yea you need a large volume tank switch.
> check in with the LP service guys in your area to see if they have this feature available.
> ...


Thanks Paul, I'll check these out.


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## iowagold (Jan 22, 2020)

some of those might be tricky at best to find with parts on back order everywhere...
but at least you have the numbers now!


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## Gen10K (Jun 25, 2020)

PatD said:


> I have a 500 gallon propane tank for the household appliances and another 500 gallon tank for the generator.


I was thinking on doing the same an get 500lbs tanks. What made me change my mind was the refill. A truck need to come and service the tanks. For that reason, I went with 100lbs instead. That way I can load them on my truck and run to town for service.

I do use an RV selector valve for the tanks
However, my Gen is smaller, so it does fine. Anyway propane is my 1st back up and gasoline my 2nd back up; the main fuel is NG.


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## tabora (Sep 6, 2018)

Our old 1960s Fisher dual tank auto-changeover propane regulator on the island has started to leak in its old age and the selector valve knob came off the top.








I was going to take it off at the end of the season and bring it home for repairs, but recently saw this one for sale online for $20. Done deal - it just arrived today!








Auto-Changeover Two Stage Propane Regulator for dual tank hook-up.

For use with propane gas
Includes 2 - 1/4in Inverted Female Flare Inlets x 3/8in Female Pipe Outlet
Use with two bulk cylinders, R.V. s, dual tank hook-ups, etc.
325,000 BTU max flow
Zinc construction
Solid brass fittings


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## iowagold (Jan 22, 2020)

cool looks like that should work!
make sure to use a sniffer or bubble check the connections.
i have seen good bottle crackers work well unless you turn off the bottles when you leave.
nothing worse than to try to run something then to find out the tank or tanks emptied due to a leak in a hose or fitting.


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## tabora (Sep 6, 2018)

iowagold said:


> make sure to use a sniffer or bubble check the connections.


I use a spray bottle of diluted bubble blow for checking connections. That's how I discovered the regulator was the culprit when I smelled the gas odor outside from the nearly empty tank #1.


iowagold said:


> nothing worse than to try to run something then to find out the tank or tanks emptied due to a leak in a hose or fitting.


Yeah, we always turn off the tanks when we leave the island, since we rarely know exactly when the next family member will arrive. We also have them tagged so everyone knows which way the valve should be pointing:


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