Question re: Gas vs. electric water heater

[fp26]

Hi everyone
Can't get a clear answer from anyone in brick and mortar stores, so figured I'd toss it out here. We have a 20 year gas water heater that is still working fine, but probably doesn't have much more life left (and we just bought the house, so are looking to upgrade before it dies). We aren't going to go tankless because the costs are way too high and everything I'm reading suggests it will take longer for warm water to get to the furthest bathrooms (which is our main issue right now). We planned to go w/ an energy efficient gas heater, but are also looking into these hybrid water heaters (heat pump + electric). What I'm trying to figure out is: which one is more efficient over the long run. I know the hybrid ones are obviously way more efficient than electric, but am unclear how they perform compared to efficient gas heaters wrt costs. It is a good $400 more, so just trying to figure out if its worth it. For reference, the ones I'm looking at are: this hybrid and this regular gas one. Appreciate any suggestions. (Planning to install a looped recirculating system to help deal w/ the issue w/ the time delay in warm water at the most distant bathrooms)

 

[Macdawgg]

I sure hope someone can answer your question because I'm in the same boat but my HWH is 8yrs old and it had a six yr warranty. It's an electric Rheem and I'm looking at that same model. I had a plumbing company come out today and quoted me $5700 for a Navien Gas water heater.

 

[Rickyman]

Just install a gas water heater, tried and true

 

[Jeff Handy]

I think that the hybrid will take heat from the room it is in, so keep that in mind.

If it is in a finished basement, that basement will be cooler.
Good in summer, but you will need to boost heat to the room in winter, as far as I know.
Or just put on a couple of sweatshirts, haha.

 

[fixitron]

Looking at just dollars, studies have shown that the hybrid heat pump water heater will save more $$ over a year, even if installed in an uninsulated and unheated basement. For upfront costs, Maryland, like many states, offers a rebate of several hundred dollars for the unit. They are usually taller than a gas heater. They require a 30 amp 240 volt power supply. They take heat from the surrounding air and "pump" it into the water using a refrigeration cycle (like your air conditioner or refrigerator that pump heat). It will cool the air around it so it cannot be enclosed in a closet, although most can be ducted for both supply and return. If the space is getting too cold, you can use electric mode (typ. 4500 watt element) only. It does take longer to recover than a gas unit. They do make some noise, much like a refrigerator. The warranties on the heat pump water heaters are often better than for the gas heaters. Check with your state energy department for more information or go to the EnergySTAR website: Upgrade Now and Save

 

[mark3885]

I’m in the same boat . My solution is to put a 19 gal 1500 watt electric tank in the master bath which is the very furthest point in the house from the tankless heater. When the bath or shower is run in the master bath, the tankless will come on and the hot water will be sent to the electric tank replacing the already hot water to the shower/bath. The result is instant hot water for the master bath , electric use to heat the tank should not be that great because of heated water coming from the tankless heater.

 

[FishScreener]

A lot of the equation depends on the utility costs where you are. I’m in the Pacific Northwest Power Grid, we have the lowest cost electric in the nation. I’m rural so gas units are propane. Propane costs more to heat the same amount of water than electric.

I manage about a hundred buildings with water heaters. The units that are off grid run on propane, the units that are on the grid get electric. My guys can work on electric units should something go wrong, they can’t do gas piping. We winterize most of the buildings every winter and drain the water heaters, and typically get twenty years out of water heaters before they have to be replaced.

The tankless units are used only where we need lots of water on demand, i.e. shower trailers serving trail crews. They go out on ten day hitches, and are then back in camp for four days before the nest hitch. This kids want long hot showers when they get back in camp. And a crew is ten people. Lit’s of water in a short period, and then no use for a week or more. The problem with tankless units is the winterizing. We typically blow out systems with compressed air at the end of the season. The flow sensors in tankless will over-spin and break, which results in a repair of more than the full cost of a tank type. Also they are really hard to winterize, because they don’t really drain fully. We finally figured out to isolate them, and pump them full of RV antifreeze in the fall using a Hudson sprayer with a garden hose fitting connected to the service valves.

The heat pump units cool whatever room they are in: Not a problem on the spaces used by fire crews in the summer and fall when it is still warm out and we are cooling the spaces anyway. We have 4 and haven’t had problems with them. Not sure we would have installed them if we hadn’t gotten a good deal on the purchase price. And they may need a lot of air flow if you enclose them. There are some now which act as part of the air tempering system fo the exchange site in newer, more air tight houses that I’m looking at.

 

[Macdawgg]

I was thinking of putting a hybird in my garage(where my old tank is now) but does anyone know if these units need to have a drain nearby? I don't have one in the garage at the moment.

 

[fp26]

Looking at just dollars, studies have shown that the hybrid heat pump water heater will save more $$ over a year, even if installed in an uninsulated and unheated basement. For upfront costs, Maryland, like many states, offers a rebate of several hundred dollars for the unit. They are usually taller than a gas heater. They require a 30 amp 240 volt power supply. They take heat from the surrounding air and "pump" it into the water using a refrigeration cycle (like your air conditioner or refrigerator that pump heat). It will cool the air around it so it cannot be enclosed in a closet, although most can be ducted for both supply and return. If the space is getting too cold, you can use electric mode (typ. 4500 watt element) only. It does take longer to recover than a gas unit. They do make some noise, much like a refrigerator. The warranties on the heat pump water heaters are often better than for the gas heaters. Check with your state energy department for more information or go to the EnergySTAR website: Upgrade Now and Save

Sure, but that's compared to a plain electric water heater. I'm talking about an efficient gas heater. Mind you, I know heat pumps are quite efficient, but gas is just a ton cheaper than electric, making heat pumps not the obvious choice here. Also, we have our water heater in a storage room in the basement (prob 4-600 sq ft) and maybe 5 feet from our gas furnace, so in theory, the heat pump should be fine there, as the room would routinely be somewhat warmer than expected).

 

[Mitchell-DIY-Guy]

One thing nobody mentioned specifically is "first hour rating" which is one of the most important ratings on a hot water tank. The heat pump model you chose shows 65; the standard gas, 86. That's a huge difference. I have no idea what you are currently living with or how big the family is, but there is a possibility that the heat pump model by itself won't supply what you need to live comfortably. You may need to time your showers, washing, dishwashing, etc.

Another thing to consider is installation cost: right now you already HAVE the gas line where you need it for a replacement gas water heater. If you go with a hybrid, now you have to have a 240V electric line put in, with the associated dual breaker. Depending on how far from your service panel this is, this might be a non trivial task and run an additional hundreds of dollars unless you can do it yourself.

 

[Macdawgg]

One thing nobody mentioned specifically is "first hour rating" which is one of the most important ratings on a hot water tank. The heat pump model you chose shows 65; the standard gas, 86. That's a huge difference. I have no idea what you are currently living with or how big the family is, but there is a possibility that the heat pump model by itself won't supply what you need to live comfortably. You may need to time your showers, washing, dishwashing, etc.

Another thing to consider is installation cost: right now you already HAVE the gas line where you need it for a replacement gas water heater. If you go with a hybrid, now you have to have a 240V electric line put in, with the associated dual breaker. Depending on how far from your service panel this is, this might be a non trivial task and run an additional hundreds of dollars unless you can do it yourself.

Mitchell-if you had to do it now knowing what you do today would you go for tankless or Hybird?

 

[fixitron]

A Heat Pump Water Heater does not heat water with electricity. It uses some electricity to pump the heat in the surrounding air (or ducted from another area or outside) into the water using a refrigeration cycle, much like an air conditioner or refrigerator. They are slow to heat up (recover) and they cool down the surrounding air (much like the refrigerator puts heat into the kitchen that it has pumped heat out of the refrigerator and freezer compartments). They can use far less energy than an all electric or gas (propane) water heater, depending on environment.
Most are "hybrid" because they also have a typical heating element for when the surrounding air is too cool or you want a faster recovery.
Tankless gas (propane) water heaters are not efficient if used for a lot of short uses. Every time you turn on a hot water tap the unit has to sense a minimum flow and then go through a purge cycle before it will fire up. It will take a minute or 2 or 3 before it will reach its maximum listed efficiency. Turn the water off and right back on and you will get a slug of cooler water because the unit has to go through the purge cycle again before it fires. Tankless is good for when you have a lot of demand for hot water in a short period. I don't recommend them for 1 or 2 person households.

 

[Mitchell-DIY-Guy]

Mitchell-if you had to do it now knowing what you do today would you go for tankless or Hybird?

I would go for a reasonably conventional gas water heater. If need be I’d install a simple recirculating system. The tankless are costly, service is a challenge, have to clean them, upsize your gas line...

Unless you try to shop between 9pm and 7am, you can buy a new gas water heater at most home centers, have it home and install it before you can even schedule a repair to your tankless or heat pump.

 

[Twowaxhack]

Hi everyone
Can't get a clear answer from anyone in brick and mortar stores, so figured I'd toss it out here. We have a 20 year gas water heater that is still working fine, but probably doesn't have much more life left (and we just bought the house, so are looking to upgrade before it dies). We aren't going to go tankless because the costs are way too high and everything I'm reading suggests it will take longer for warm water to get to the furthest bathrooms (which is our main issue right now). We planned to go w/ an energy efficient gas heater, but are also looking into these hybrid water heaters (heat pump + electric). What I'm trying to figure out is: which one is more efficient over the long run. I know the hybrid ones are obviously way more efficient than electric, but am unclear how they perform compared to efficient gas heaters wrt costs. It is a good $400 more, so just trying to figure out if its worth it. For reference, the ones I'm looking at are: this hybrid and this regular gas one. Appreciate any suggestions. (Planning to install a looped recirculating system to help deal w/ the issue w/ the time delay in warm water at the most distant bathrooms)

It would be easy for you to compare the two models as to which would be more efficient. I’ll let you do that part.

You say that you’re going to circulate the water. This is the weak point in your system. You need to insulate the circulating loop heavily.

In the homes that I’ve built I always locate the source of hot water close to the fixtures.

To get an energy efficient home it starts with good design.

Imagine how much energy is wasted over the life of a home by circulating the water. From the water heater having to reheat the same water to the power the pump uses. Cost of the pumps and the wear on the piping.

 

[Twowaxhack]

Please don’t confuse energy efficiency with the cost of the energy to you.

For example, a regular electric tank is very energy efficient but the cost of electricity may be way higher for you than the gas it would take to heat your water with a less energy efficient gas model.

 

[Twowaxhack]

Formula for electric water heaters recovery.

Recovery GPH = wattage/2.42 x Temp rise in Fahrenheit.

 

[Bill Foster]

I know I'm coming to this party late and I'm a newbie on Plumbing Forums, but I figured I'd add my two cents on the "is the hybrid water heater worth it?" What I'm about to say is just my opinion, so take it for what you paid for it. I can tell you that in my experience, it all really depends on consumption demand. If it's a single person living in a house and are not putting a lot of load on the unit, it'll get by fine for them. There are really two complaints on these systems that I hear constantly: recovery time and cost to repair them. The recovery time on these hybrid units that are in heat pump mode will never compare to that of a gas 40,000 BTU or higher tanked water heater or certainly not a tankless. Most times I see people keep them in hybrid mode, which means they're losing the efficiency they thought they were getting when they bought it. They're in hybrid mode because they're not getting the recovery they need because if they wash dishes and have the washer going, they are taking tepid or cold showers. If they have teenagers taking long showers? Forget it. The gas units being made today are rock solid, are easy to work on, and have readily available parts at cheap prices. It is a tried and true system, and if you're mechanically inclined, watch YouTube, and can follow manufacturer instructions, you can do a lot of troubleshooting & repairs yourself. You won't be doing that on a tankless unit or a heat pump. I come from the school of 'keep it simple stupid.' I could put any unit I want in my own home at wholesale cost + wholesale cost of fittings & accessories. Recently my old heater took a dump and I chose to go back with a Bradford White 50gal NG Power Vent because of this very principle. For residential purposes, it really boils down to demand. Commercial applications are a different animal altogether, but for the average homeowner, I tell them to keep it simple.

 

[Twowaxhack]

The most repairable water heater in my area is the standard electric with 4500 watt elements.

There’s nothing on them I can’t repair in a few minutes except the tank itself.

In a pinch I’ve installed 120v elements and plugged them directly into the wall to heat a tank of water.

 

[Bill Foster]

The most repairable water heater in my area is the standard electric with 4500 watt elements.

There’s nothing on them I can’t repair in a few minutes except the tank itself.

In a pinch I’ve installed 120v elements and plugged them directly into the wall to heat a tank of water.

Exactly. I get the craze over the tankless stuff, and hear it regularly. But what you just said is proof in the pudding of staying with the simple mouse trap.

 

[Twowaxhack]

Exactly. I get the craze over the tankless stuff, and hear it regularly. But what you just said is proof in the pudding of staying with the simple mouse trap.

Don’t get me wrong, A tankless is awesome for a huge tub or 2-3 teenagers in the house or a custom shower.

But I like to supplement a tank type with a tankless. Then you get the best of both worlds.

You also have a backup if one fails or the power goes out. And you get endless water.

There’s no substitute for proper planning and expert execution while installing any mechanical system, especially plumbing.