The unit is scheduled to start running after 9AM. It probably should start a bit later than that because my solar system can barely produce 900w of power at 9AM in late winter, if it’s sunny of course. I think it should start in the afternoon so even if it’s cloudy winter day the solar system can carry the heat pump without struggling.
But looking at the home energy chart, the heat pump probably consumed less than 2kw each day given we do a few hot showers and do other daily cooking and cleaning routines, so it’s not a big deal at all even if I don’t have solar.
Water is pre-heated and stored in the well insulated steel water tank, so at the nearest tap the hot water is almost instant, even more instantaneous than my old gas one. Guess it takes a few seconds for a gas heater to warm up its heat exchange pipes which obviously not needed by the water tank.
The unit is almost silent when it’s running. I can only identify its noise when I’m within 5 meters with it. If I’m in my kitchen, I can certainly tell if the fridge is working but not the heat pump which sits just outside of the kitchen wall.
This heat pump also works like a good combo with my induction cook top. For instance when I start to cook some noodle, I use hot water from the water tank, which is an instant boost from 10°C to 60°C. This saves me some time waiting for the water to boil and also some energy thanks to heat pump’s very high thermal co-efficient, ie. only 1/6th energy is used to heat water to 60°C, then 100% energy to heat up to 100°C.
Now I only hope this thing runs reliably and won’t have a break down. Fingers crossed 🙂
After weeks of waiting, thanks to lock downs in Victoria, I finally have a 315L Sanden Heat Pump installed, replacing my who-knows-how old gas instantaneous water heater. The job has been done professionally by SolarFlow, kudos to the team!
I can label myself an environmentalist who keeps trying to minimize my own carbon footprint but this heat pump is also a logical and economical decision.
First of all, a heat pump works like a reverse air conditioner: it extracts heat from the outside and heats up inside. In other words, unlike gas or old school electric water heater, heat pump doesn’t use energy to generate heat but only transfer it. During my little research on heat pump products, I noticed that amongst all heat pumps Sanden stands out as the most efficient one: with 1 unit of energy consumed it can transfer up to 6 units of energy, a 600% coefficient of performance(COP)! This means comparing to my gas water heater which probably has <60% of efficiency the heat pump is a tenfold more efficient. And high efficiency means less running cost.
With solar panels the perk of being an electric appliance is that when the sun is shining, the heat pump runs(almost) for free. Just to be clear, I still need to pay for water regardless weather. With a rough calculation, I paid about 500 dollars a year for hot water with the old gas heater, so this heat pump can possibly pay for itself in 10 years. ( I found it interesting when it is a V8 diesel SUV no one asks if it will pay for itself later but people do ask this question if it’s renewable related products )
Fingers crossed though, the tank is warranted for 15 years but the heat pump itself only has 6 years of warranty.
The temperature of the hot water out of the tank feels like 60°C, which means it needs to mix with some cold water to achieve a comfortable temperature, so the 315L tank practically can supply me much more than 315L of hot water depending on the desired temperature.
Last but not least it’s also quieter when running. I could definitely tell if the gas heater was running 5 meters away from it, but won’t be so sure about the heat pump.