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Water heater: Gas to electric conversion illegal in California?

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I contacted a water heater company saying gas conversionsto hybrid electric storage is "illegal" in California. He said he received 15 calls about this.

I did some research. https://www.energy.ca.gov/2015publi...ters/chapter_5-Water_Heating_Requirements.pdf

5.2.2.3 Storage Heat Pump Water Heater A storage heat pump water heater is an electric water heater that uses a compressor to transfer thermal energy from one temperature level to a higher temperature level for heating water. It includes all necessary auxiliary equipment such as fans, storage tanks, pumps, or controls. DOE classifies heat pump water heater under the category of electric storage water heater, and it must meet the federal minimum efficiency standards, depending on tank size. Heat pump water heaters are not allowed through the prescriptive approach to compliance but can be installed using the performance approach as long as the water heating energy budget is not exceeded. (See Section 5.5 for more information on the energy budget and performance path to compliance.)

The only way is to comply through the "performance approach":

5.5.1 Energy Budget Calculation The computer performance approach allows for the modeling of water heating system performance by taking into account building floor area, climate, system type, efficiency, and fuel type. The standard design water heating budget is defined by the corresponding prescriptive requirements. The performance method allows for modeling alternative water heater and distribution system combinations. Some of these options will offer compliance credits, and others will result in penalties. 5.5.2 Systems Serving Single Dwelling Unit In the case of single dwelling units, any type or number of water heaters can theoretically be installed. The calculated energy use of the proposed design is compared to the standard design energy budget based on a single natural gas instantaneous water heater with a standard distribution system. Adding multiple water heaters to a single-family design will generally result in an energy penalty in the water heating budget that must be offset elsewhere in the total energy budget.

Though a heat pump hybrid water heater could perform more efficiently than a traditional gas storage water heater. I don't think anything electric, heat pump or not, can outperform a natural gas instantaneous water heater.

Case closed for me.
 
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I contacted a water heater company saying gas conversionsto hybrid electric storage is "illegal" in California. He said he received 15 calls about this.

I did some research. https://www.energy.ca.gov/2015publi...ters/chapter_5-Water_Heating_Requirements.pdf

5.2.2.3 Storage Heat Pump Water Heater A storage heat pump water heater is an electric water heater that uses a compressor to transfer thermal energy from one temperature level to a higher temperature level for heating water. It includes all necessary auxiliary equipment such as fans, storage tanks, pumps, or controls. DOE classifies heat pump water heater under the category of electric storage water heater, and it must meet the federal minimum efficiency standards, depending on tank size. Heat pump water heaters are not allowed through the prescriptive approach to compliance but can be installed using the performance approach as long as the water heating energy budget is not exceeded. (See Section 5.5 for more information on the energy budget and performance path to compliance.)

The only way is to comply through the "performance approach":

5.5.1 Energy Budget Calculation The computer performance approach allows for the modeling of water heating system performance by taking into account building floor area, climate, system type, efficiency, and fuel type. The standard design water heating budget is defined by the corresponding prescriptive requirements. The performance method allows for modeling alternative water heater and distribution system combinations. Some of these options will offer compliance credits, and others will result in penalties. 5.5.2 Systems Serving Single Dwelling Unit In the case of single dwelling units, any type or number of water heaters can theoretically be installed. The calculated energy use of the proposed design is compared to the standard design energy budget based on a single natural gas instantaneous water heater with a standard distribution system. Adding multiple water heaters to a single-family design will generally result in an energy penalty in the water heating budget that must be offset elsewhere in the total energy budget.

Though a heat pump hybrid water heater could perform more efficiently than a traditional gas storage water heater. I don't think anything electric, heat pump or not, can outperform a natural gas instantaneous water heater.

Case closed for me.
They're selling the Rheem hybrids at my local Home Depot. Somebody isn't enforcing it, lol.

I was thinking gas-electric hybrid water-heater. Gas for primary-heating, heat-pump for maintenance heating. I guess they don't make that yet?

This except a gas/electric hybrid version of it: Natural Gas Heat Pump Water Heater Tech Under Development for US | Proud Green Home
 
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The 2016 CA Energy Code (Title 24, Part 6) applies to new construction, additions, and remodels (called alterations in the Energy Code). But people will do small remodels without a permit, so it doesn't get enforced, hence the electric water heaters available at box stores in CA.

I believe the lack of a prescriptive option for a heat pump electric water heater in the 2016 CA Energy Code is recognized as a flaw, so hopefully the option will show up in the next version.

My understanding of the performance approach for alterations is that if changing two or more components, you get to compare the energy budget of the proposed configuration with the energy budget of the existing components, as long as you have a pre-construction inspection to verify the existing components and their performance. So if you combine your water heater change with something else (e.g. adding attic insulation), it would be enough to show that your heat pump water heater uses less energy than your existing water heater (or if it uses more energy, that you've made up for it with an improvement in the second component).

This is based on a cursory reading of section 150.2(b)(2) of 2016 CA Energy Code, which you can find here: 2016 Building Energy Efficiency Standards - California Energy Commission

Cheers, Wayne
 
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A few months ago I pulled a permit for two sub panels, an EV charging receptacle and a heat pump water heater. This was in Sonoma County, California. The biggest issue during inspection was the grounding of the water connections.
@Ampster Has your house ever have an electric water heater? Did you need to install an electric water heater circuit to add the heat pump water heater (HPWH)?
 
@Ampster Has your house ever have an electric water heater? Did you need to install an electric water heater circuit to add the heat pump water heater (HPWH)?
I bought the house 18 months ago and dont believe it ever had an electric water heater. I added a 30 Amp circuit but it was only a 20 foot run which I did myself. When we moved in we bought an electric dryer but it already had a circuit. No issues there converting from gas but no permit needed.
Bottom line I don't believe anything my gas utility tells me anyway. In my case, they (PG&E) are the same as my electric provider. They are playing with the Title 24 energy rules anyway. I would love to see them try to prosecute for a Title 24 violation given California's RPSgoals. I used to have an induction cooktop in my other house which was all electric. It beats gas in speed and you don't have to breath those fumes.
 
Just under 1 year late on a reply here, but here you go.

HPWHs can be installed for alterations to existing buildings under last year's Energy Code, assuming they are reasonably efficient. See:

https://energyarchive.ca.gov/title24/2016standards/documents/2016_water_heater_efficiency_guide.pdf (page 2)

To determine your climate zone by zip code, visit https://energyarchive.ca.gov/maps/renewable/BuildingClimateZonesByZIPCode.pdf.

Under the current code (2019 Code, effective for permit apps applied for on/after 1/1/2020), HPWHs can still be installed, but additional easily achievable measures must be met. See Section 150.2(b)1H of the 2019 Energy Code for more.
 
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HPWHs are on sale at HD; I've never seen them this cheap.

Screen Shot 2020-05-11 at 5.05.30 PM.png
 
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I had a 65 gallon Rheem (Ruud) put in a few months ago. It's working great and pulls 3kWh-7kWh a day. They gave an App that lets you flip demand modes and see the power usage.

I'm perpetually mystified as to why these aren't more popular... I've spoken to people that will merrily pay $6k for 2kW of solar but cringe at the idea of replacing their electron guzzling resistance water heater for ~$1k even though the end result is the ~same......
 
I'm perpetually mystified as to why these aren't more popular... I've spoken to people that will merrily pay $6k for 2kW of solar but cringe at the idea of replacing their electron guzzling resistance water heater for ~$1k even though the end result is the ~same......

I made my own "hybrid" system. In the summer I solely use a heat pump water heater
Electric Hot Water Heater | Accelera® | Stiebel Eltron USA

And in the winter I primarily use a boiler for my radiant heat and an indirect water heater. I then drop the temperature of my heat pump water heater to @ 100 degrees or less, to act like a preheater.
 
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It's on Home Depot's website right now, I found it just by googling: Rheem Performance Platinum 50 gal. 10-Year Hybrid High Efficiency Smart Tank Electric Water Heater-XE50T10HD50U1 - The Home Depot

HD also notes $600 in rebates in my area, this is pretty tempting. My current HWH is gas (and a 6 year unit into it's 10th year), will have to see what sort of electrical connection this would need.

dm me your PayPal. You just saved me more money than Jake at State Farm, I quite literally picked this up Thursday at the old price and haven’t unboxed it.
 
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I think you’ll see a big push for heat pump water heaters in California starting next year. The state sees them as a way to reduce carbon fuel use, as well as a way to soak up the surplus solar PV during the day by setting when they preheat water. Discussion currently of adding them to the SGIP program. My utility Edison is going to be offering a rebate soon too.
 
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. My utility Edison is going to be offering a rebate soon too.

They actually had rebates on them last year also. I got a $500 credit from SCE. I did pretty well considering that I also got it when it went on sale for $1000 at some point, and also I claimed the $300 Fed credit too.

All in all including the parts I paid to install, it cost me about $400 and is now saving me about $20 a month in Gas. I have Solar, and with the <1 kWh it uses most days, I've not seen a hit yet in my Electric use either, and am still going negative. Love the fact it cools the garage also and soaks up the heat from the cars charging. Its a win win.

My only remaining fossil fuel possession is the clothes dryer, so I'm going to replace that also with a heat pump one... that is when I can be bothered to run a 240V supply to our laundry on the second floor.
 
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