Gas/Electric water heater March 20, 2023, 03:29:30 pm Has anyone upgraded from a gas water heater to a combo gas/electric water heater? Curious on the wiring required for power and the old and new switch.I have purchased the Dometic WH-6GEA and am in the process of installing now. I plan on running power to the inverter so as to remain hidden. It didn't come with a switch for the electric so I am going to purchase one but am concerned I won't be able to add it separately or will need to buy a double switch and disable the one on the main control panel. The wires coming from the panel are Brown, White, Blue. The wires coming from the new water heater are Green, White, Blue, Orange.Any help or advice would be greatly appreciated! 1 Likes
Re: Gas/Electric water heater Reply #1 – March 20, 2023, 07:37:26 pm "I have purchased the Dometic WH-6GEA and am in the process of installing now."That's the very item I requested (not an option) when I ordered my 30' in 2004. Asked Steve Newton if they would install the dual-fuel WH and was given a flat NO! How simple it would have been, a length of Romex and a switch and ...done. The one on a previous TT worked just fine! Why pay to burn your LP when electric is part of the fee that comes with full hook-ups? 3 Likes
Re: Gas/Electric water heater Reply #2 – March 20, 2023, 10:16:50 pm Quote from: PennyPinchingGlobetrotter - March 20, 2023, 03:29:30 pmI have purchased the Dometic WH-6GEA and am in the process of installing now. I plan on running power to the inverter so as to remain hidden.Dometic seems to indicate the electric element draws 1400W. Through an inverter, with 90% efficiency, the draw at 12V would be about 130 Amps. I don't know how long it might have to run to bring it up to 140F, but likely at least 1/2 hour, which with lead-acid batteries would bring you down about 100 Ah or more. If running on propane, you would hardly notice the amount used, and time to warm about half. Electric use makes sense only if on shorepower.Steve 3 Likes
Re: Gas/Electric water heater Reply #3 – March 21, 2023, 03:07:52 am I could see the usefulness of a dual-heat-source water heater if the electric source was AC from shore power. I don’t see the usefulness of DC electric source, either.
Re: Gas/Electric water heater Reply #4 – March 21, 2023, 10:16:33 am The biggest issue I see with an electric water heater on a 30A circuit is the difficulty running any of the higher amp appliances like the air conditioner, microwave, etc. at the same time. 1 Likes
Re: Gas/Electric water heater Reply #5 – March 21, 2023, 11:19:50 am Quote from: Ed & Margee - March 21, 2023, 10:16:33 amThe biggest issue I see with an electric water heater on a 30A circuit is the difficulty running any of the higher amp appliances like the air conditioner, microwave, etc. at the same time. Agree - we had a dual water heater with the Travel Trailer. It was VERY easy to blow a circuit breaker when on shore power. It seems like our 92LD had a dual system. Perhaps problems with blowing circuit breakers was why LD was so set against them. 1 Likes
Re: Gas/Electric water heater Reply #6 – March 21, 2023, 01:00:40 pm "Perhaps problems with blowing circuit breakers was why LD was so set against them."That's a good guess. Of course, one could argue that the air conditioner and microwave are both on one leg of the 30A circuit, and you can't run both of those at the same time without tripping a breaker. But perhaps Lazy Daze's reasoning was that while buyers would not want to do without a microwave oven or air conditioner, as long as the water heater was usable on propane they'd probably be OK with that.In addition, it's obvious when either the air conditioner or microwave oven is in use. But when the water heater is running on 120 VAC power it's silent, so it would be easy to forget and leave it on--and if you're used to living in a house with an always-on water heater, it's easy to do just that. That could lead to a lot of annoying breaker trips, and an increase in complaints to the factory. I wish they had installed dual-powered water heaters just the same, but I can see their reasoning.My Airstream, like many RVs, does have a propane/120V water heater, and I use it on shore power when that's available. I'm careful not to do so when running the air conditioner (and I've removed the microwave oven). And there's little chance of my leaving the water heater on for more than fifteen or twenty minutes, because when I want to take a shower--the only thing I use hot water for--I push a button on an electronic thermometer that's preset to beep when the water reaches the ideal temperature for showering. When I hear the beep, I turn off the water heater and step into the shower. (More details on my web page "The One-Gallon Shower.")
Re: Gas/Electric water heater Reply #7 – March 21, 2023, 01:50:59 pm Hi Andy; I routinely run the A/C in hot weather, and use the microwave at the same time. Mostly at Caravan Club full hookup sites. I've never had the 30A circuit breaker trip. I don't turn off the converter or any other breakers either. Lazy Daze did provide a lower power Panasonic microwave oven (780 Watts cooking, 1100W input) that may be smaller than what most people have in newer rigs. I also don't have the heat strip in the A/C or heat pump A/C, that newer 2013 or so rigs have. My 13,500BTUH A/C is lower power also than some people who opted for 15K BTUH A/C's. I'm sure that an additional as you say 'silent' load like a water heater would cause load problems for a 30Amp limited plug in or generator connection. RonB
Re: Gas/Electric water heater Reply #8 – March 21, 2023, 02:03:39 pm "Electric use makes sense only if on shorepower."And that is exactly when it defaults in... my '94 30' Holiday Rambler TT came equipped with the dual fuel WH. When I connected to shore power the water heater would immediately begin to heat. If I were not on AC I had to use a switch to activate the LP source for hot water. I owned that trailer for 10 years, traveling to Alaska, the east coast and Texas a number of times. Not once did I ever have a breaker trip that I could attribute to the water heater. 1 Likes
Re: Gas/Electric water heater Reply #9 – March 21, 2023, 04:44:45 pm Reminds me of a pair of switches I once saw on a Fleetwood Bounder: 1 Likes
Re: Gas/Electric water heater Reply #10 – March 21, 2023, 04:47:31 pm This reminds me of an issue I have: When the inverter is turned on, the refrigerator switches over to AC from gas. It runs just fine, however it consumes significant battery energy, so we have to remember to press the “AUTO” button on the refrigerator to force it to use gas (propane, not gasoline, of course).We found out that forgetting to switch the refrigerator to gas can have a startling consequence: with the inverter on, when running the microwave, and sometime later the refrigerator thermostat calls for cooling, the inverter is happy to deliver higher AC amps, which draws higher DC amps, which can exceed the current limit of the Battle Born LiFePO4 batteries, which then turn themselves off. If this happens at night, it gets TOTALLY dark inside the motor home. After a few seconds, the batteries turn themselves back on, the lights come back on, leaving you to wonder what just happened? Some day, I’ll look for a signal from the inverter that indicates it is providing AC rather than shore power or the generator, and install a relay on the AC to the refrigerator. If I don’t switch to a compressor refrigerator first, which would need more batteries and solar panels.
Re: Gas/Electric water heater Reply #11 – March 21, 2023, 08:59:16 pm Quote from: Keith S - March 21, 2023, 04:47:31 pmWe found out that forgetting to switch the refrigerator to gas can have a startling consequence: with the inverter on, when running the microwave, and sometime later the refrigerator thermostat calls for cooling, the inverter is happy to deliver higher AC amps, which draws higher DC amps, which can exceed the current limit of the Battle Born LiFePO4 batteries, which then turn themselves off.When not connected to shorepower, I do two things: switch off the converter and switch the fridge off auto mode. No need to have it otherwise unless the weather is bad enough to need to run the generator, and the inverter is happy running nuker, hair dryer, etc. Last two weeks we had lots of rain on the CA coast, but always got just enough solar in between to fully recharge our LFPs. Last early summer in Glacier N.P. we had rain every day and NO solar, so I ran the generator twice in 5 days for 1.5 hrs each, and that was enough. For that I would temporarily switch on the converter, but left the fridge on gas-only.Steve
Re: Gas/Electric water heater Reply #12 – March 21, 2023, 09:23:01 pm How long does your fridge remember switching it out of AUTO and into GAS?I’m thinking it is reset to AUTO upon power ON.Our typical procedure is to plug in to shore power two days before departure, and spare the propane until we depart. 1 Likes
Re: Gas/Electric water heater Reply #13 – March 21, 2023, 11:42:45 pm When I installed an inverter/charger in my Class C Jayco, I moved the water heater AC line to the 30A breaker output, where it can only be run on shore or generator power. We use our heater like Andy: turn it on (propane or electric), wait till the water is hot enough (about 95-100F displayed on the thermometer we use), then turn if off. It is never left on to cycle by itself.The refrigerator AC line was also moved to the 30A breaker output, same as the water heater line, and can only use AC when shore or generator power is available. It is always left on Auto, since it draws a measly 300W at most.Of course, we still have to mindful of what else is running before switching on the electric water heater: generally, no A/C or microwave at the same time, even on 30A shore circuits. 1 Likes
Re: Gas/Electric water heater Reply #14 – March 21, 2023, 11:52:21 pm Quote from: RonB - March 21, 2023, 01:50:59 pm Lazy Daze did provide a lower power Panasonic microwave oven (780 Watts cooking, 1100W input) that may be smaller than what most people have in newer rigs. I also don't have the heat strip in the A/C or heat pump A/C, that newer 2013 or so rigs have. My 13,500BTUH A/C is lower power also than some people who opted for 15K BTUH A/C's.Hey Ron,Must be your lower power AC.I tripped when I foolishly tried to pop some popcorn in the microwave while I was running the 15,000 BTU heat pump (AC) in Morro Bay.Dave
Re: Gas/Electric water heater Reply #15 – March 22, 2023, 01:07:58 am Quote from: Keith S - March 21, 2023, 09:23:01 pmHow long does your fridge remember switching it out of AUTO and into GAS?I’m thinking it is reset to AUTO upon power ON.Once the fridge is 'on', it will stay in gas mode once you set it there. If you hook to shorepower, it will stay in gas mode. If you switch on the inverter, it will stay in gas mode. If you turn the fridge 'off' - such as when fueling up, it will come on in auto, until you switch it to gas mode. When we are going to travel, I switch it back to auto, since a separate inverter powered by the alternator powers the fridge enroute.Steve
Re: Gas/Electric water heater Reply #16 – March 22, 2023, 01:19:37 am Quote from: Eric Greenwell - March 21, 2023, 11:42:45 pmWhen I installed an inverter/charger in my Class C Jayco, I moved the water heater AC line to the 30A breaker output, where it can only be run on shore or generator power. We use our heater like Andy: turn it on (propane or electric), wait till the water is hot enough (about 95-100F displayed on the thermometer we use), then turn if off. It is never left on to cycle by itself.The refrigerator AC line was also moved to the 30A breaker output, same as the water heater line, and can only use AC when shore or generator power is available. It is always left on Auto, since it draws a measly 300W at most.How is it that your 30A breaker differentiates between AC power sources? 1 Likes
Re: Gas/Electric water heater Reply #17 – March 22, 2023, 12:48:07 pm I bought the Camco hybrid water heater kit to add to my water heater. Only draws 425 watts, ~4 amps. Heated probe screws into the drain port on the water heater. Never have to use my gas for heating water when plugged in. I added an inline duplex plug box under the lowest drawer on my midbath. A wire runs to the outside plug thru that area. I added the on/off switch inside the closet just above the water heater. Very happy with the unit so far, going on 2 years. Link............. Hot Water Hybrid Heat Kit - Easily Converts Any 6-Gallon RV LP Gas Water... 1 Likes As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
Re: Gas/Electric water heater Reply #18 – March 22, 2023, 02:02:03 pm So with the 400AH LiF batteries and 450 watts of solar, on a sunny day my batteries turn off fully charged at 9:00 AM to 11:00 AM in the morning. In Morro Bay there wasn't much sun on a few days but I never went below 70% 'state of charge'. Wondering how to put the extra solar capacity to use, a 12volt dc heater rod for the water heater seems like a valid use for unused solar panel capacity. I know others here who have excess solar panel capacity that might be interested. I turn off my water pump, and open the faucet to relieve pressure in the house plumbing system while the tank is heating up. Generally I use the water heater just for showers or dishwashing, so I don't keep it hot all of the time. A manual switch to move the solar output to an electric element might work. DC Water Heater Element 12 Volt 60 Watt with Thermostat 140 Degrees F | eBay If it would fit into the drain hole, this might work. RonB
Re: Gas/Electric water heater Reply #19 – March 22, 2023, 02:04:56 pm We did that exact same installation back in 2020. We were full time in Oregon during lock down with AC power etc. I think it heats the water up in about a half hour. We added a short extension cord running from our duplex plug box to the hot water access so you have 120v when you open the hot water heater door. Our 98~MB did not have 120v outside power on the passenger side of the home. Karen~Liam 98 ~ MB NinA
Re: Gas/Electric water heater Reply #20 – March 22, 2023, 04:03:23 pm "I bought the Camco hybrid water heater kit..."Looks similar to the device once offered for sale called a "Hot Rod". Some folks used it and liked it, others shied away because of warranty conflicts, me for one.Yes, it was meant to be inserted in the drain hole and it was recommended that it be replaced once a year because of depletion.
Re: Gas/Electric water heater Reply #21 – March 22, 2023, 04:32:57 pm Hi LazyBones; That Rod shouldn't 'deplete' or corrode with an aluminum tank. Any corrosion with a steel tank might be a problem, with a zinc body heater as the sacrificial anode. But in a non steel tank, and stainless rod, it should be OK. I may try that 12v heater rod, when I get the time. Or I could get the 120VAC one and run it off the 2KW inverter. Tempting fate with the batteries if I forget to turn it off. Max insolation is about 300 watts/ hour on a sunny day. Of course if I'm not running the A/C I could also use hook ups. RonB
Re: Gas/Electric water heater Reply #22 – March 23, 2023, 12:49:52 pm We were hesitant about getting the Camco 120v kit, we thought we would never use it because we are rarely plugged into shore power and do not use the generator except to exercise it. 2020 lock down changed it for us and it made sence to use it while we were plugged in. Now we find ourselves plugged in on more camp sites and can sit outside without the jet engine noise of the hot water heater. When I installed the probe I left plenty of wire so the probe can be removed on occasion to drain and check out the hot water heater. Karen~Liam 98 ~ MB NinA
Re: Gas/Electric water heater Reply #23 – March 23, 2023, 01:12:03 pm Hi Liam; You can reduce the noise involved from running the water heater on propane by adjusting the mixture sleeve. It changes with altitude, but is pretty quiet when the right mix is set. You have a nice LED light for the ceiling of your kitchen area. I have a larger one and smaller one like that for my 'stick and brick' kitchen. Do you run that off of battery power? Is it a 12Vdc model, or is it only active when you have 110VAC? You could make that dual purpose by adding 12v white LED's inside the housing, still operated by the standard wall switch at the MB coach door and the 12vdc wires already there. Something like this: but I prefer daylight white. DD00WM 20pcs Pre Wired Warm White SMD 3528 Led Lamp Light Set 12V ~ 18V 0.24W RonB As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
Re: Gas/Electric water heater Reply #24 – March 23, 2023, 02:01:26 pm Ron, I thought of a dual 12v/120v light setup but that would require additional 120v wiring. So we opted to leave it as 12v. Basically we buy 120v light appliances and wire them for 12v and use LED 12v bulbs. They have worked well in our LD for 5+ years now. The biggest drawback is that they can buzzz when dimmed. We buy from Amazon and test the bulbs and if they buzz they go back. We have tested many brands from Amazon and have stuck with the ones that are quiet. We used this application when building our Son's tiniHouse and it is outfitted with house hold lighting appliances with 12V bulbs, many are on dimmers. Actually we carry spare 12v LED bulbs and I do not recall replacing any of the original bulbs yet. I thought possibly the motion of bumps on and off road (Trona Pinnicles) would have caused some failiers? Karen~Liam 98 ~ MB NinAHomeSelects 6102 Light, 12", Brushed NickelProgress Lighting P3713-09 Inspire Two-Light Flush Mount, Brushed Nickel - -...Amazon.com: OPALRAY DC 12V-24V Low Voltage Input LED Bulb, Classic A19(A60)... As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.