Financial comparison - heat pump water heater vs tankless

[Donald]

Has anyone done a financial comparison for say 20 years between an 80 gal hybrid and a 9 gpm propane tankless. I chose 20 years as that's the lifespan of a tankless propane water heater.

From a conservative point of view, the hybrid lasts 10 years (so two over 20 years) and tankless lasts 20 years.

The hybrid is close to $3000 each. So $6000. The tankless is $1600. Both plus install.

The garage is unheated so unsure how well the hybrid will work in the winter DE when it's cold. Garage is 47F now.

Obviously the heat pump will work very well in the summer. Dehumidifier is an extra bonus.

And hybrid heat pump water heater does not use a fossil fuel.

Sure seems you would need to save a lot via the heat pump.

Some of the comparisons may be between an electric water vs a hybrid electric water heater.

 

[Rand]

what is 6000? you running triple 80 gallon tanks?

Edit: oh I see what you did.

I dont think there is any reason to believe a propane tankless will last 20 years..

Also I just found 80 gal for 2000 and there is a rebate of 30% so probably more like $2500 installed minus 30%
and my local utility (when does this happen in ohio) has a 750$ rebate... should check yours.

If 50gal is enough those are about $1250

The install is much more complicated on the propane. Usually need 200k btu service(pipe size) and extra valves for flushing every 6-12 months depending on water quality and air intake/exhaust needs installed etc.

the marketing on tankless reads like buying an EV. Everything is great.

you need really good water or it wont last. Maintenance is a pain although partially mitigated with proper install/valving.
Wait for the water to heat up and make it to faucet.. waste more water/time.
Propane is expensive over 9x more than a NG hot water heater for me.(but my NG is cheap)

 

[Donald]

what is 6000? you running triple 80 gallon tanks?

Edit: oh I see what you did.

I dont think there is any reason to believe a propane tankless will last 20 years..

Also I just found 80 gal for 2000 and there is a rebate of 30% so probably more like $2500 installed minus 30%
and my local utility (when does this happen in ohio) has a 750$ rebate... should check yours.

If 50gal is enough those are about $1250

The install is much more complicated on the propane. Usually need 200k btu service(pipe size) and extra valves for flushing every 6-12 months depending on water quality and air intake/exhaust needs installed etc.

the marketing on tankless reads like buying an EV. Everything is great.

you need really good water or it wont last. Maintenance is a pain although partially mitigated with proper install/valving.
Wait for the water to heat up and make it to faucet.. waste more water/time.
Propane is expensive over 9x more than a NG hot water heater for me.(but my NG is cheap)

My old plumber in NY still gives my plumbing advice even though I live in Delaware. He suggests a Rinnai tankless.

Wife has a Jacuzzi and our 50 gallon propane water heater with the thermostat turned all the way up does not fill the Jacuzzi to the level should would like so any water heater upgrade needs to do a better job. So I think I need a 80 gallon.

I am pretty sure I have high pressure and low pressure propane regulators. So I think I might need the low pressure regulator changed along with maybe 10 feet of gas line.

With a heat pump you pay a lot for the actual heat pump and when the tank leaks in 10 years you toss the whole thing and buy new.

I don't have 220V at the location where I would install the hybrid water heater so one that runs on 120 V would be best.

 

[oil pan 4]

They'll save you money until they break.
I have had both tankless and heatpump hot water heaters and I'll never buy another one of either type ever again.
Old-school tank style either gas or electric for me.

 

[dlundblad]

I’d have as little propane appliances as possible.

Your prices for both units seem high. Also, the anticipated 20 year life for the tankless with only 10 on the hybrid seems off too. Maybe do the math with both at 10. (Both should easily do that.) Anything after that is a gift.

 

[Rogueman2016s]

I don't have 220V at the location where I would install the hybrid water heater so one that runs on 120 V would be best.

Resistive heating element @ 120v will be costly no matter what. Propane no bargain either if you have the option for natural gas that would be your best choice, 2nd the propane. I don’t think a water heater with heat pump would be able to keep up filling jacuzzi tubs.

 

[John105]

My guess is that the salesmen have done the comparison and use it to sell the more costly heater.

Sometimes, there's a rhyme/reason to sticking with traditional things. I think the same curiosity has been applied to ductless mini splits. They are more efficient, but what is the longevity. Or electric cars. etc.

 

[John105]

what is 6000? you running triple 80 gallon tanks?

Edit: oh I see what you did.

I dont think there is any reason to believe a propane tankless will last 20 years..

Also I just found 80 gal for 2000 and there is a rebate of 30% so probably more like $2500 installed minus 30%
and my local utility (when does this happen in ohio) has a 750$ rebate... should check yours.

If 50gal is enough those are about $1250

The install is much more complicated on the propane. Usually need 200k btu service(pipe size) and extra valves for flushing every 6-12 months depending on water quality and air intake/exhaust needs installed etc.

the marketing on tankless reads like buying an EV. Everything is great.

you need really good water or it wont last. Maintenance is a pain although partially mitigated with proper install/valving.
Wait for the water to heat up and make it to faucet.. waste more water/time.
Propane is expensive over 9x more than a NG hot water heater for me.(but my NG is cheap)

When I had to replace my gas hot water heater it had begun to leak so I really didn't have time to do much research. Maybe if I did it again, I'd get not the high efficiency one, but the one in the middle. I should have steered the conversation but the lady on the phone said if you are not sure if there's a 120V outlet near the heater (there was but it's also for the washing machine) then you can only get the standard model.

I think there was an energy star model that was also web enabled for only $20 more, and it exhausted differently. Not straight out, it still used the chimney....

I'm not interested in taking chances. Probably 20 years from now the jury will be back in on some of these things and the paradigm shifts. Or, it's like appliances. Everyone laments and says they don't make 'em like they used to.

 

[Donald]

Resistive heating element @ 120v will be costly no matter what. Propane no bargain either if you have the option for natural gas that would be your best choice, 2nd the propane. I don’t think a water heater with heat pump would be able to keep up filling jacuzzi tubs.

We would only need to fill the Jacuzzi a couple of times a week. We have a walk-in shower. A 120V element costs the same as a 220v element, both are 100% efficient converting electricity to heat. Many people run the hybrid water heater on heat pump only so the element voltage does not matter.

 

[Rogueman2016s]

120V element costs the same as a 220v element, both are 100% efficient converting electricity to heat.

?

The amperage is double, I don’t understand how it could be equal.

Example,
3500w element @ 120v let’s say 30a mathematically its slightly less.

Same element powered by 240v is 15a

 

[BMWTurboDzl]

Has anyone done a financial comparison for say 20 years between an 80 gal hybrid and a 9 gpm propane tankless. I chose 20 years as that's the lifespan of a tankless propane water heater.

From a conservative point of view, the hybrid lasts 10 years (so two over 20 years) and tankless lasts 20 years.

The hybrid is close to $3000 each. So $6000. The tankless is $1600. Both plus install.

The garage is unheated so unsure how well the hybrid will work in the winter DE when it's cold. Garage is 47F now.

Obviously the heat pump will work very well in the summer. Dehumidifier is an extra bonus.

And hybrid heat pump water heater does not use a fossil fuel.

Sure seems you would need to save a lot via the heat pump.

Some of the comparisons may be between an electric water vs a hybrid electric water heater.

The only real comparison you can make is in energy used over time and then do a cost comparison once you convert to BTU.

 

[Donald]

The tankless water heaters have a SS heat exchanger so that should last 20 years hopefully. Other parts certainly could break.

 

[Donald]

?

The amperage is double, I don’t understand how it could be equal.

Example,
3500w element @ 120v let’s say 30a mathematically its slightly less.

Same element powered by 240v is 15a

Forgetting any standby loss. To get 80 gal of cold water from 50F to 150F requires 64000 BTU. A BTU is the amount of heat needed to raise the temperature of 1 lb of water by 1 degrees F. Water is 8 lb / gallon. Converting BTU to watts you get 18756 watts. So however you can dump in 18756 watts into the water the cost of the electricity will be the same. Be it a 100 amp coil running at 220V or a 10 amp coil running at 120V. One takes a lot longer.

 

[skyactiv]

I’m happy with my 65 gallon Rheem Hybrid. In Donald’s case, I’d probably go with what his plumber suggested. Sone members of Bitog put too much concern on reliability.

 

[oil pan 4]

I’m happy with my 65 gallon Rheem Hybrid. In Donald’s case, I’d probably go with what his plumber suggested. Sone members of Bitog put too much concern on reliability.

Reliability is all that matters.

 

[Donald]

The only real comparison you can make is in energy used over time and then do a cost comparison once you convert to BTU.

That's only part of the equation. One other part is how long they will last. And then there is cost per BTU for electricity and for propane. Doubtful they rise at the exact same rate.

The difficult to figure out is lifespan. Tankless heat exchanger will last longer than the tank of a heat pump. But many other components. Most can be repaired or replaced by themselves.

 

[BMWTurboDzl]

That's only part of the equation. One other part is how long they will last. And then there is cost per BTU for electricity and for propane. Doubtful they rise at the exact same rate.

The difficult to figure out is lifespan. Tankless heat exchanger will last longer than the tank of a heat pump. But many other components. Most can be repaired or replaced by themselves.

Ya I don't know how you estimate repair costs. Every customer has their own threshold for when it's cost effective for them to replace vs repair. Tankless do have a regular maintenance interval. Tanked not so much other than replacing the anode every couple of years and occasionally draining the tank to was out sediment. To each their own.

 

[Hillbilly Deluxe]

At this time, there is no need for me to do a minute's worth of cost benefit analysis. My house is currently set up to run a 50 gallon gas (propane) direct vent water heater. I can buy a scratch-n-dent model exactly like I have now for about $500, a new 2-gal expansion tank about $50 and that's all I need to change the water heater out. So $600 and my time.

If you haven't had work done by a professional plumber who does highly skilled and competent work, prepare yourself for a shock. Their rates are generally $150-180/hour now and many charge a minimum of 6 hours for a water heater change out. To go from a typical gravity vent gas or electric water heater to a hybrid/heat pump or tankless, you might be looking at $1500-3000 in labor alone, not including miscellaneous materials, parts, etc, plus the water heater(s). You could be looking at $5-10k for some elaborate "energy saving" water heater set up that you have to amortize over 20 years.

At a mere $6500 cost above $1800 (typical 40 or 50 gal water heater change out rate today), you're going to need to save $325+ per year for a consistent 20 years JUST TO PAY FOR THE ADDED EXPENSE. When the 20 is up, all you've done is pay for the added expense.

Let's say you saved $450/year. Now you're "making" $100/ year ($2000 total) on a ~$6500 investment. That's about 2% per year, not compounded. So 1.25% at best... ?

Lotta work, lotta hand-ringing, lotta head-scraching and lotta hogwash to listen to by salespeople to make 1.25% IMO....

 

[Hillbilly Deluxe]

Tanked not so much other than replacing the anode every couple of years and occasionally draining the tank to was out sediment. To each their own.

I'm 52, I've never replaced an anode rod in my life in a water heater. I've installed 7-8 water heaters in my time, most at a home I was living in, a couple in neighbor's homes.

I've had trouble draining ONE water heater, it was less than 2 years old. It was an American Water Heater in 1999 or so. The local gas company was giving those away, they had recently switched from Bradford-White. It was FULL of stuff. Evidently whatever was breaking apart in the heater or something in the heater causing enormous scale/etc build up. I wasn't able to get it drained out. I was able to waddle it out the laundry room door, on the deck that was 9' above the ground and a friend helped me get it over the railing and onto the ground below. I drove around, rolled it on to a trailer and hauled it off.

I've done the "periodic maintenance drain" on a few and rarely seen anything come out. I understand that some areas they do need to be drained...

For most, those old-school technology 40 and 50 gallon gas, direct-vent water heaters are extremely hard to beat. They heat water very well, they don't "run when you're not home" (other than a pilot light) and they heat water when there's no electricity...

 

[BMWTurboDzl]

I'm 52, I've never replaced an anode rod in my life in a water heater. I've installed 7-8 water heaters in my time, most at a home I was living in, a couple in neighbor's homes.

I've had trouble draining ONE water heater, it was less than 2 years old. It was an American Water Heater in 1999 or so. The local gas company was giving those away, they had recently switched from Bradford-White. It was FULL of stuff. Evidently whatever was breaking apart in the heater or something in the heater causing enormous scale/etc build up. I wasn't able to get it drained out. I was able to waddle it out the laundry room door, on the deck that was 9' above the ground and a friend helped me get it over the railing and onto the ground below. I drove around, rolled it on to a trailer and hauled it off.

I've done the "periodic maintenance drain" on a few and rarely seen anything come out. I understand that some areas they do need to be drained...

For most, those old-school technology 40 and 50 gallon gas, direct-vent water heaters are extremely hard to beat. They heat water very well, they don't "run when you're not home" (other than a pilot light) and they heat water when there's no electricity...

Me neither. In fact I can't replace the anode even if I wanted. I guess Cobb water doesn't precipitate out all that much. I rarely get much out when I drain the tank. Perhaps a tsp of mineral from a 50 gallon tank.