Amps x volts =watts. double the voltage half the amps. electric company charge by watts.
20 x120= 240 watts
10 x 240= 240 watts
Watts ÷ volts = amps
3500 ÷ 120 = 14.58 amps
3500 ÷ 240 = 29.16 amps
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Financial comparison - heat pump water heater vs tankless
- Thread starter Donald
- Start date
20 x120= 240 watts
10 x 240= 240 watts
Watts ÷ volts = amps
3500 ÷ 120 = 14.58 amps
3500 ÷ 240 = 29.16 amps
Almost all the stuff I get out of mine is too big to exit through the drain valve.
I have to ask.... how do you get it out?
If we were talking natural gas vs hybrid, then nat gas would win in almost all scenarios. But propane is quite expensive and the tankless water heaters consume a lot of gas. The nat gas unit I had in CA was a 100k BTU unit. That's the same size as a furnace.
Also, there is extra cost in water usage as it takes a lot longer for hot water to start running. I have yet to see anyone include this in the cost calculations. And you absolutely have to be on top of the annual maintenance on these units. Scale buildup will ruin them pretty quickly.
How about just a propane water heater? They truly don't consume as much as we are led to believe? The difference, at least for me, was literally few dollars per month when I compared my natural gas water heater I had in Canada to the tankless heater I had in California. And that was likely because CA has a lot more expensive nat gas. In the same market, the savings are almost non existent.
Tankless heaters truly shine in cottages or summer homes. But under normal, everyday usage they offer no savings, or very little savings at best.
Also, there is extra cost in water usage as it takes a lot longer for hot water to start running. I have yet to see anyone include this in the cost calculations. And you absolutely have to be on top of the annual maintenance on these units. Scale buildup will ruin them pretty quickly.
How about just a propane water heater? They truly don't consume as much as we are led to believe? The difference, at least for me, was literally few dollars per month when I compared my natural gas water heater I had in Canada to the tankless heater I had in California. And that was likely because CA has a lot more expensive nat gas. In the same market, the savings are almost non existent.
Tankless heaters truly shine in cottages or summer homes. But under normal, everyday usage they offer no savings, or very little savings at best.
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I am a little worried about my current water heater going and being forced to take what HD or Lowes has in stock. The hybrid take days maybe two weeks to come in.
What I am surprised about is you cannot find large propane hot water heaters until you go to commercial ones and they are thousands. Must be much heavier built not just a bigger tank.
Use a bigger hole such as the hot water heater element screw hole.
I wish they made the heat pump water heater in kind of a two part system. The heat pump and tank. Replace only the tank if it leaked. I know they made ad-on heat pumps for water heaters many years ago.
So another thought is I could install the hybrid water heater myself with help from a neighbor just because of the weight. With a propane tankless I would need to at least get the vent and gas line done by a professional. The current vent for the propane tank heater is galvanized steel and a condensing gas tankless require SS or PVC due to acidic condensate.
Not much help but I think I wish I had a propane tank heater instead of our propane tankless. We didnt have a choice, it's what the builder uses. Too many things can go wrong, too much maintenance, and A LOT of complaining in this area about replacement costs of tankless.
Im not saying you are wrong to want to switch, we only been in this house 9 months, bought new and first time having a tankless. It works good enough but I know/doubt very much we are ever going to save any money by having one. My fear is it breaking down or ever needing replacement. Its a Rinnai
Im glad we have VERY soft water here and hope maybe I can get away two years before being forced to clean or have someone clean the coil/exchanger. That in itself makes it much more expensive than a tank heater.
Im not saying you are wrong to want to switch, we only been in this house 9 months, bought new and first time having a tankless. It works good enough but I know/doubt very much we are ever going to save any money by having one. My fear is it breaking down or ever needing replacement. Its a Rinnai
Im glad we have VERY soft water here and hope maybe I can get away two years before being forced to clean or have someone clean the coil/exchanger. That in itself makes it much more expensive than a tank heater.
The do. Its called a Sanden SANCO2.
Nyle system used to also make an add on heat pump for your existing water heater called the geyser. They stopped making them which is a shame because I would buy one right now if they still made them.
I installed my HPWH in 60min including a run to ace hardware 4 miles away
and the drain line.
I did have lowes deliver it to my basement and tipped the guy a 20. they used that forearm forklift.
I wrestled it up onto a double layer of pavers so the wiring would reach.
As long as there is a drain its certainly not hard.
I'd consider having 240v run. you would be ready for a PHEV and able to use the vastly more common 240v models... as well as have backup 4500w(5500w?) elements if for a week its -10f out and too cold in garage.
At propane prices last year resistance electric heat isnt even that much worse.. although about 3 to 3.5x worse than Heat pump mode.
I put in a HPWH because it was $2900 to get a power vent NG water heater installed.. by the less-ripoff plumber.
and I get dehumidification so I can subtract 7-10 months of running a dehumidifier or fans.
HPWH was 212+79 delivery 50 plumbing pieces(already had most) -$300 federal rebate
I had a first gen Rheem that wasnt great initially and was hit by lighting surge. but warranty covered that and it worked flawless until it rusted out at a union due to bad installer.
My self installed AO smith I expect 8-14 years.. and the hot water part is basically free due to the electricity savings + the savings of no fan or dehumifidier.
I run it at 149f. upstairs the outside radon fan is louder than the water heater. Its not quiet.. but not annoying either.
just for curiosity I looked up my old invoice I was off a couple bucks they charged taxes on delivery
and the drain line.
I did have lowes deliver it to my basement and tipped the guy a 20. they used that forearm forklift.
I wrestled it up onto a double layer of pavers so the wiring would reach.
As long as there is a drain its certainly not hard.
I'd consider having 240v run. you would be ready for a PHEV and able to use the vastly more common 240v models... as well as have backup 4500w(5500w?) elements if for a week its -10f out and too cold in garage.
At propane prices last year resistance electric heat isnt even that much worse.. although about 3 to 3.5x worse than Heat pump mode.
I put in a HPWH because it was $2900 to get a power vent NG water heater installed.. by the less-ripoff plumber.
and I get dehumidification so I can subtract 7-10 months of running a dehumidifier or fans.
HPWH was 212+79 delivery 50 plumbing pieces(already had most) -$300 federal rebate
I had a first gen Rheem that wasnt great initially and was hit by lighting surge. but warranty covered that and it worked flawless until it rusted out at a union due to bad installer.
My self installed AO smith I expect 8-14 years.. and the hot water part is basically free due to the electricity savings + the savings of no fan or dehumifidier.
I run it at 149f. upstairs the outside radon fan is louder than the water heater. Its not quiet.. but not annoying either.
just for curiosity I looked up my old invoice I was off a couple bucks they charged taxes on delivery
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Only partially true (The 'locked in heat pump mode' that is.)
The elements will engage at cold temps regardless of if you have it locked to heat pump-only mode. Mine will do it 2-3 times a year if it gets cold enough in the garage.
3 Times so far here in 2024, where you see the spikes far above the normal 5-6 KWh is when it decided that it was futile to run the pump and switched to resistive.
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This is exactly the setup they get in Australia. I was watching Dave at EEVBlog a while back talk about his install. He went from a gas tank to the heat pump.
Looks like a mini-split with a tank.
So it's not cheap. But one could replace the tank on its own if it failed. They keep the water in the tank at 170F.
The actual heat pump unit flows water to/from the tank. They talk about the heat pump being outside. What happens when it gets cold out and the heat pump is nut running. Won't the water lines freeze?
If it was close then I would choose against fossil fuels.
What's wrong with fossil fuels? They are the most efficient for heating.
It's a personal view to help us get to greener energy.
Using far more resources, decreasing reliably and increasing complexity to save some CO2 and clame it's "greener" is at the very least deceptive.
Where do you think most electricity comes from?
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