Electric WH is 1/3 my power bill. Heat pump or Tank-less propane?

[zimm]

My 2018 house was built with an el-cheapo grade State 50 gal 240v water heater. The energy score is at the bottom of the scale. It's installed in a closet under the stairs.

It's only 5 years old but I'm thinking about a more efficient replacement. Family of 4, not a lot of hot water demand. 2 showers in AM, 2 in PM. But the house has 3 full baths and we sometimes have guests.

Options:

Heat pump or hybrid. I already have the 240v in place. Ventilation is a concern- I can swap out the closet door for louvered. The door opens to the main family room/front hall area. Condensate- there's a pan with floor drain - maybe tee into that? Or I can run a new one. House is on a crawl space and outside wall is at end of closet.

Tankless gas. I have a propane fireplace in the living room so the gas line is right under the floor. Would have to see if it needs to be upsized, I know it tapers down as the gas line makes it's way across the house from tank-->cook top-->furnace-->2 fireplaces. Again, outside wall for venting is right there.

My concern with the heat pump is in the winter, it's going to be getting all its "heat" from my propane powered furnace anyway, so am I gaining much? However we have hot summers and the AC can use all the help it can.

 

[Twowaxhack]

I wouldn’t replace it because of the power bill. I wouldn’t use a heat pump water heater.

I’d try to use less hot water if I wanted to “ save “ money.

If you go gas tankless you may need to upgrade your propane tank and gas lines. This would take care of the extra demand for guests. You’d never run out of hot water but you might run out of propane. You’ll never run out of electricity.

You’re in a tough spot

 

[GymBag]

You could install an industrial-grade timer, set for daytime heating and turn it off for most of the night. My parents had that and it saved a good amount of money.

 

[Twowaxhack]

You could install an industrial-grade timer, set for daytime heating and turn it off for most of the night. My parents had that and it saved a good amount of money.

With his family taking 2 showers in morning and two at night the standby loss would be minimal at best. I doubt a timer would provide any energy savings.

 

[Twowaxhack]

Who piped that water heater ?

 

[Ludington]

I wouldn’t replace it because of the power bill. I wouldn’t use a heat pump water heater.

I’d try to use less hot water if I wanted to “ save “ money.

If you go gas tankless you may need to upgrade your propane tank and gas lines. This would take care of the extra demand for guests. You’d never run out of hot water but you might run out of propane. You’ll never run out of electricity.

You’re in a tough spot

No heat pump water heater ? Don't like them ?
Personally, I think there to new in the market, lord knows who works on them if they break.

 

[GymBag]

With his family taking 2 showers in morning and two at night the standby loss would be minimal at best. I doubt a timer would provide any energy savings.

We did the same at home when the timer was installed- it made a difference, but I have no way of finding how much. An energy audit would be best, before any decisions are made.

 

[Mitchell-DIY-Guy]

...new in the market, lord knows who works on them if they break.

Well, since it is basically a heat pump (like you may have in an HVAC system) you get an HVAC firm (or those who sold you a heat pump water heater in the first place) to work on it.

All heat pumps make heat on one side, and cold on the other. If you are making heat to put into water, the cold then has to go somewhere. If it is in your house, then you have to make up the heat with space heating. A bonus in the summer as it may reduce your a/c bill. Maybe less of a concern if its in a basement but not all homes or regions have basement. Also less of a concern if its outside, which some places have outside water heaters.

While the timer per se might not save THAT much--many electric companies offer different rate structures with time of day usage for things like space heating, water heating, etc. Worth a look into.

 

[Ludington]

Well, since it is basically a heat pump (like you may have in an HVAC system) you get an HVAC firm (or those who sold you a heat pump water heater in the first place) to work on it.

All heat pumps make heat on one side, and cold on the other. If you are making heat to put into water, the cold then has to go somewhere. If it is in your house, then you have to make up the heat with space heating. A bonus in the summer as it may reduce your a/c bill. Maybe less of a concern if its in a basement but not all homes or regions have basement. Also less of a concern if its outside, which some places have outside water heaters.

While the timer per se might not save THAT much--many electric companies offer different rate structures with time of day usage for things like space heating, water heating, etc. Worth a look into.

I know my hot water is the majority of my household electric bill, but the cost break even point of installing a hpwh over what it saves isn't good enough. It would save me roughly 200 -250 a year so that's 6 to 8 years to break even. Plus lots of extra break points. Tempting, as itvwould help cool my basement. But I think they have to come down in price.

 

[RS]

How is your water quality? If your water has minerals in it, it can mean high maintenance on a tankless water heater. How good are you at troubleshooting and doing maintenance on appliances? One or two service calls is going to cost more than your electric bill. Conventional electric water heaters are pretty maintenance free.

 

[BlueSkyHigh]

I wouldn’t replace it because of the power bill. I wouldn’t use a heat pump water heater.

I’d try to use less hot water if I wanted to “ save “ money.

If you go gas tankless you may need to upgrade your propane tank and gas lines. This would take care of the extra demand for guests. You’d never run out of hot water but you might run out of propane. You’ll never run out of electricity.

You’re in a tough spot

Cold water showers are invigorating!

 

[zimm]

Who piped that water heater ?

It is pretty janky isn't it? I have no idea who the builder used on this house. The cheapest one I bet. I have no idea why it has a "high loop" of pipe, that isn't needed right?

Sounds like I should leave it alone for now. I thought saving $60/mo on the heater would be nice, plus my 9000 watt generator could power it during a power outage. But I am a bit worried about running an air conditioner under my stairs- I know it'll be noisy and my propane furnace doesn't need to work any harder than it already is.

 

[RS]

The high loop is probably there to reduce thermosiphon circulation, and that is saving you money

 

[Twowaxhack]

We did the same at home when the timer was installed- it made a difference, but I have no way of finding how much. An energy audit would be best, before any decisions are made.

When I say it wouldn’t make a difference I mean that it’s not worth doing, not that you couldn’t save $5 on the monthly bill. You Probably couldn’t pay for the cost of the timer with the savings over the life of the timer in this man scenario. Maybe you could if the demand was only once a day or once every 2-3 days.

New heaters are insulated fairly well and being his demand is equally spaced between morning and night there’s not much standby loss for the hours between the demand.

 

[Twowaxhack]

It is pretty janky isn't it? I have no idea who the builder used on this house. The cheapest one I bet. I have no idea why it has a "high loop" of pipe, that isn't needed right?

Sounds like I should leave it alone for now. I thought saving $60/mo on the heater would be nice, plus my 9000 watt generator could power it during a power outage. But I am a bit worried about running an air conditioner under my stairs- I know it'll be noisy and my propane furnace doesn't need to work any harder than it already is.

It’s suppose to have 18” of metal piping before connection to the water heater. But that doesn’t mean it has to be straight up !

 

[zimm]

Ah I see. 18" of metal. It looks taller than it because the photo is wide angle.

As for the timer- Not only do the kids shower at 7pm, but the dishwasher runs at 9pm. So I could have it shut down from 11pm-5am, but I doubt it'll save much that way.

Also don't I have to worry about bacteria building up if the temp drops below 120?

Again, I think I'll just leave it alone.

 

[Twowaxhack]

Ah I see. 18" of metal. It looks taller than it because the photo is wide angle.

As for the timer- Not only do the kids shower at 7pm, but the dishwasher runs at 9pm. So I could have it shut down from 11pm-5am, but I doubt it'll save much that way.

Also don't I have to worry about bacteria building up if the temp drops below 120?

Again, I think I'll just leave it alone.

Legionella, yes but you need to be hotter than 120 to kill it.

If you shut the heater down from 11-5 the heater is just going to fire off and run at 5am to make up for any heat loss it had from 11-5 so you’re just delaying the inevitable with a timer.

I wouldn’t install a timer.

If you want to save on hot water, use less. That’s the answer.

 

[MicEd69]

If you shut the heater down from 11-5 the heater is just going to fire off and run at 5am to make up for any heat loss it had from 11-5 so you’re just delaying the inevitable with a timer.

It's similar to living in New Orleans and turning off your A/C from 8;00AM to 5:00PM because no one is home. By the time the A/C wrings out all the water from the air and cools down all the furniture and inside walls of the now hot house, the A/C has to run continuously until the wee hours of the morning. Something NOT to do.

 

[Twowaxhack]

It's similar to living in New Orleans and turning off your A/C from 8;00AM to 5:00PM because no one is home. By the time the A/C wrings out all the water from the air and cools down all the furniture and inside walls of the now hot house, the A/C has to run continuously until the wee hours of the morning. Something NOT to do.

Yes, same here. I live about 2hrs east of New Orleans. I ran a lot of copper in the garden district of New Orleans in the late 1980’s.

 

[chinarus]

I have a large tankless conversion in my primary house and had to run multiple new 240 connections.
I also have 2 smaller tankless in a rental house and the larger one required multiple 240 lines. Both properties are standard Heat Pump HVAC. Different tradeoffs depending on HVAC zones, water source/sewer fees, distance from tankless to faucet/shower, family patience to wait on hot water, etc. There are small tankless that can go under a sink that don't require unusual wiring.
Heat pump is barely adequate for very cold days but has 8KW Heat Coil that will activate when the Heat Pump looses efficiency due to outside temp.

I am satisfied with utility bills - my wife is not so satisfied waiting on hot water sometimes.