Revisiting hot water heat pumps

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#3406374 22-Aug-2025 10:36

WWHB:

The Sanden is more expensive and takes a little bit more work to install due to it being a split system.
As far as I am aware there is no monobloc style system with a stainless steel cylinder.
The Sanden would outperform everything else on the market (excluding the reclaim and Panasonic units). The CO2 units have much faster recovery and would be cheaper to run than anything thing else available. The Sanden can only be supplied and installed by approved suppliers, I would check with Rheem about a local one to you (the reason I say that is that I am approved but don’t appear on the list on their website). In my case the Sanden is a bit cheaper, quite a bit cheaper than the Reclaim. The Panasonic is mid price point between the 3 units. I had a Sanden at my place for the last few years, I recently moved home and my biggest regret was not taking that system with me.

Thanks for the detailed response - appreciate it! We're Auckland, so finding supplier probably not a problem. Enquiring now about the price premium.

Cheers

acetone

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#3406379 22-Aug-2025 11:03

Kickinbac:

My real world consumption for 2 adults and 2 teenage children - 2.66 kWh per day, this is based 132 days from 1st April 2025 to 11th August 2025

Before the upgrade, our average on a medium pressure hot water cylinder is about 10.8 kWh per day. Sorry that is based on a couple of months last year.

This is only based on data since HWHP installed at end of March 2025. I use a Shelly PM1 to log the power use.

As for hot water use by teenagers its hit and miss between not showering for days and spending an hour in the shower! 🙄 This data is hard to gather.

I'm not doing anything special with running times, it runs when it needs to.

This is a Panasonic CO2 HWHP, split type with 250 litre cylinder.

That is a pretty good saving in power, I bet you noticed that on the power bills.

DjShadow

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#3413737 11-Sep-2025 12:14

Our Carrier HWP just gone in (plumber from A2W plumbing still here as I type), it's a lot bigger than how it appeared in the promotional material. Natural Gas now fully redundant and hoping Genesis will have someone over as early as tomorrow to take the meter out.

Real good timing too as we got an e-mail from Genesis yesterday indicating our line rate was going to $1.63/day and the use rate going from 16c to 24c per kW.

johno1234

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#3413762 11-Sep-2025 13:20

DjShadow:

Our Carrier HWP just gone in (plumber from A2W plumbing still here as I type), it's a lot bigger than how it appeared in the promotional material. Natural Gas now fully redundant and hoping Genesis will have someone over as early as tomorrow to take the meter out.

Real good timing too as we got an e-mail from Genesis yesterday indicating our line rate was going to $1.63/day and the use rate going from 16c to 24c per kW.

May I ask how much the installation cost was (excluding the cost of the equipment)?

I though swapping out the gas califont for a heat pump in the same location would be a reasonably inexpensive job of disconnect and reconnect. However I've seen numbers of a few thousand for the plumber time and materials - maybe a lot of different valves and connectors?

davidcole

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#3413763 11-Sep-2025 13:28

Anyone have radiators? Specially hot water heated ones. Is there an electrical equivalent of a Gas boilers (essentially a Rinnai infinity type unit, but must include a water pump and a return feed because radiators are closed circuits).

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Kickinbac

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Ultimate Geek
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#3413781 11-Sep-2025 14:19

acetone:

Kickinbac:

My real world consumption for 2 adults and 2 teenage children - 2.66 kWh per day, this is based 132 days from 1st April 2025 to 11th August 2025

Before the upgrade, our average on a medium pressure hot water cylinder is about 10.8 kWh per day. Sorry that is based on a couple of months last year.

This is only based on data since HWHP installed at end of March 2025. I use a Shelly PM1 to log the power use.

As for hot water use by teenagers its hit and miss between not showering for days and spending an hour in the shower! 🙄 This data is hard to gather.

I'm not doing anything special with running times, it runs when it needs to.

This is a Panasonic CO2 HWHP, split type with 250 litre cylinder.

That is a pretty good saving in power, I bet you noticed that on the power bills.

Our power bill is approximately the same cost as last year. I shudder with the power cost increases and when I add that saving to our current bill!

Kickinbac

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Ultimate Geek
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#3413784 11-Sep-2025 14:24

davidcole:

Anyone have radiators? Specially hot water heated ones. Is there an electrical equivalent of a Gas boilers (essentially a Rinnai infinity type unit, but must include a water pump and a return feed because radiators are closed circuits).

There are hot water heat pumps specifically for radiator heating circuits. Look up Mitsubishi Electric Ecodan https://www.mitsubishi-electric.co.nz/hydronic-hot-water-heat-pump/ or Central Heating NZ https://www.centralheating.co.nz as a start for information.

DjShadow

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#3413805 11-Sep-2025 14:52

Don't have the final invoice in front of me but ballpark $8500 incl install which included removing of the Califont and the Pad it is sitting on. I used A2W plumbing based in Lyall Bay who are advertising this unit currently on their Facebook page.

I did notice quicky I can hear the unit running from the lounge which is it backs onto but didn't sound any louder when I opened the window

johno1234

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#3413816 11-Sep-2025 15:32

DjShadow:

Don't have the final invoice in front of me but ballpark $8500 incl install which included removing of the Califont and the Pad it is sitting on. I used A2W plumbing based in Lyall Bay who are advertising this unit currently on their Facebook page.

I did notice quicky I can hear the unit running from the lounge which is it backs onto but didn't sound any louder when I opened the window

Thanks - are you able to guess what it was excluding the cost of the heat pump kit? I'm trying to ascertain the plumber's cost.

DjShadow

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#3413818 11-Sep-2025 15:43

Placemakers have the 280L ver of the prev generation unit for $4657. I think they only took about 3 hours to install this before doing a few other small jobs I had for them.

Jase2985

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#3413825 11-Sep-2025 15:57

johno1234:

DjShadow:

Don't have the final invoice in front of me but ballpark $8500 incl install which included removing of the Califont and the Pad it is sitting on. I used A2W plumbing based in Lyall Bay who are advertising this unit currently on their Facebook page.

I did notice quicky I can hear the unit running from the lounge which is it backs onto but didn't sound any louder when I opened the window

Thanks - are you able to guess what it was excluding the cost of the heat pump kit? I'm trying to ascertain the plumber's cost.

Wait till they get the final invoice.....

DjShadow

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#3414065 12-Sep-2025 10:47

Got the final invoice and thankful the quoted price was the final price, this is a copy/paste:

Price $8401.29

Carrier are one of the most trusted heat pump brands in the world and offer a market leading 10 year warranty. This R290 unit with a 300L capacity offers excellent efficiency at a remarkable price point.

✅Ideal for medium to large households
✅Recovery time, 71/Lhr
✅10yr warranty
✅Frost protection
✅COP of 4.6
✅R290 Refrigerant

Included in this quote is the following:
- Disconnect and dispose of existing HWU.
- Supply and install Carrier Blue 300L Hot Water Heat Pump complete with associated valves and pipework.
- Connect hot and cold water to existing supplies.
- Electrical connection.
- Cap gas at meter.
- Base for HWC.
- Test and commission.

Not Included in Quote:
- Removal of gas meter. Please note this must be done by your gas provider.

Gas meter coming out today so thankful that is one less headache charge wise on the power bill!

johno1234

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#3414085 12-Sep-2025 11:31

Sounds like the installation component is roughly $3500 then which is consistent with what I have heard elsewhere. I'm still not understanding why this is so expensive.

It would not be possible to financially justify the expense of replacing our gas water heater with a heatpump - too expensive.

timmmay

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#3414086 12-Sep-2025 11:32

What's the payback time on a $8400 hot water cylinder? It would depend on your water use I guess. I wonder how that compares with a standard hot water cylinder. You'd probably assume power price rises of maybe 5% per year.

I was thinking of replacing our standard cylinder with a heat pump cylinder, but when I looked at the payback period it was fairly long - I can't remember exactly.

Stu1

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#3414103 12-Sep-2025 12:07

johno1234:

Sounds like the installation component is roughly $3500 then which is consistent with what I have heard elsewhere. I'm still not understanding why this is so expensive.

It would not be possible to financially justify the expense of replacing our gas water heater with a heatpump - too expensive.

It’s a lot of money add on top of that replacing gas central heating it’s over 30k, that’s a lot of gas I’m staying put on the infinity as well

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