The gas (storage) hot water system is looking like it’s on its’ last legs – it’s about 13yrs old.
We’re looking to replace it but I’m interested to hear from anyone who’s had any experience with heat pump hot water systems, especially if you live in Perth?
cheers for your advice....
no, just looking @ options currently....
(edited previous post - misread it thinking you were talking about PV, not solar HWS)....
We are in WA and the house we bought had solar hot water system already installed. Have to say it awesome, we had a gas system in the past and was starting to get expensive.
Only cost for solar is the replacement of the sacrificial anode.
+1 for solar HW!! had one installed on my roof, never looked back, so comfy to use with good taps compared to gas.
on a side note you can keep your wine in the same room as the heat pump as it produces cold on the outside !
Solar with heat pump. We put an instantaneous gas HWS in about a decade ago and I can't fault it. Solar wasn't as good then as it is now otherwise we would've gone that way.
Have gone from Solar with heat pump to heat pump only.....sadly.
The system on the old house was faultless. We installed the system and worked out the system broke even with the cheaper options at about year 3 - we had it for 5 before we sold
The externally located heat pump system on the new place is a few years old but prone to blowing the controller (twice).
The heat pumps are very efficient. Usually a coefficient of production of around 3 to 4. It goes down a bit as the water temperature increases, but up to 60deg C it is up around 4.
The problem is in the initial expense. They are (or were, I haven't checked them recently) very expensive.
I see a few places up north are using them. I don't know why when it's so sunny up there you would think solar would be the obvious choice.
I was thinking maybe use solar/electric with some solar panels to help supply the electricity when needed.
Solar panels can still supply significant power even when it's a bit shady.
I like the idea of the heat pump from the point of view of the technical cleverness of them but I think they might lack a bit in the practical aspects.
As with all air conditioners (heat pumps) they have a limited life and are expensive to replace.
It means when either the water tank springs a leak or the heat pump wears out, you have to replace the whole lot.
I know they say you can just replace parts of it if it packs up, but the reality is, when it does pack up they will say it's cheaper in the long run to replace the whole lot. A bit like replacing car parts really. These days you mostly just junk the lot and buy another one. (Well some people do,.. but I don't. 
. )
solar with electric backup works a treat. Heat pumps are just too complicated especially if it's just backing up your solar. Gas backup for the solar would of been handy this weekend with no power and cloudy cold weather but then how often do you get a cyclone in may
Single storey house or two storey ???
Solar panels on a second storey roof should be more expensive to install....
I have a Bosch instantaneous gas heater (with pilot flame - the auto start one I had in the past was a pain in the a..e due to tiny spiders or bugs regularly nesting in the warm gas jet and blocking it up at unfortunate times). Simple to use, cheap to buy and cheap(ish) to run unless you have teenage daughters. The pilot jet sometimes blows out but generally only once or twice a year and mine is exposed to the seabreeze side of the house. It's also easy to adjust for the temperature changes over the seasons.
I've been using an instantaneous gas system for years (Rinnai). Small neat outdoor unit with a pilot light which kicks in when a certain volume of water passes through it. Brilliant. Cheap to run. You get charged for what you use.
Ifyou live in perth go roof top solar ,simple last a long time.heat pumps unreliable costly to repair.
There is nothing hi tech about the heat pump, it's just a window rattler on reverse cycle.
The few I've seen are quite noisy, and motors are D.O.L, not dc inverters.
Don't get me started about pcb's
I like the Turtlehunter's post.
I am going with solar hot water, I have been told that solar hw puts out mains pressure hot water.
Can someone confirm this?
I also had a storage hot water system about 5 years ago,
had some reno's done and coverted to a Rinnai instantaneous system
bloody brillant, never run out of hot water, As Pitbull said, pay for what you use.
Select to expand quotep train said..
I am going with solar hot water, I have been told that solar hw puts out mains pressure hot water.
Can someone confirm this?
we are on our second solar edwards system. first lasted 18 years. replaced as the older generation panels were getting dodgy. on a subzero morning there would be pressure surges through the mains that the panels couldnt handle. new gen with glycol jackets are way more efficient. almost too hot , so i would recommend regular checks of the overheat valve.
here in kal dont use ceramic lined steel storage tanks as they have to shipped by road and develop microcracks and give very poor life.
solar edwards have stainless. so great.
the new type of Vacumn tube solar uses electricity to pump the water, so i cant see the point.
in the adverts they claim the lowest electricity use of any storage system, but the fine print that flashes up says tested in summer in Broome. surely in broome you wouldnt even bother with a booster on a regular solar?
We just got quotes for replacing our old hot water system.
$2000 for Rennai and $2000 after government rebate for a solar with the same rennai back up.
I think we'll just go for Rennai. We had it in the past in our old place and it was great.
All those panels will be just extra hussel I reckon. For what savings ? What if the roof needs to be repaired ?
Been doing a fair bit of research with sparky and plumber for my new house,
Quantum heat pump, $3,700, approx$400 per year running cost
Similar for solar inc booster usage for winter
The sparky has a standard hwsu on a timer
Unit cost $800, $95 last quater power use
The more exspensive options need to run trouble free for a long time to break even, then if you have a failure out of warranty you'll be behind, also will someone give you an extra $3700 if you sell because you've got a heat pump or solar? The main reason I was thinking heat pump was to use the cold air which they produce and vent into the house, cheaper to hose the missus off in the back yard juddy
If you install a heat pump HWS in your garage, it will become an air conditioned garage. How is that for getting the best out of your energy buck???
That's only a good idea in summer when you might like a nice cool garage.
Wot happens in winter when you go to get in the car and find the windscreen is all iced up? 
huh? Well????
I'm still to decide between the heat pump and solar but one thing comes to mind is recovery. Heat pumps are very quick to recover from over use but solar are slow. But I can only think of a few times I have ever emptied a HW of hot wat
Select to expand quotepweedas said..
That's only a good idea in summer when you might like a nice cool garage.
Wot happens in winter when you go to get in the car and find the windscreen is all iced up? huh? Well????
Uuummmm. Life is great in the sunshine state or something like that.
Select to expand quotecisco said...
If you install a heat pump HWS in your garage, it will become an air conditioned garage. How is that for getting the best out of your energy buck???
Wouldn't work so efficient, they prefer a moderate temperature, so having them in a cold climate wouldn't be that great
I've also noted that as they basically suck air in having them in coastal regions or on in protected areas of the house can lead to failures due to salt air
They are temperamental to surrounding temperatures as we fitted 3 inline at dirk Hartog island for the accomadation , we found the middle unit was being starved from the 2 outer units so wasn't operating at the same level as outer units
I paid a bit more for a 600 litre tank for my solar HWS with gas back up. It's great but the gas comes on whether it's needed or not. I now turn off the gas unless sits been cloudy for a couple of days in a row.
gas bill looks very svelte.
no lack of hot water issues.
probably/surely a default but a close mate had half his unit destroyed (by steam and flooding) by the explosion of his heat pump.
