Giantkiller
New Member
Thanks so much for all the information. I just purchased a pallet of New 390watt panels for $112.29 apiece plus tax. Delivered. Will be installing them later this summer for the heated driveway.
DC water heater.
- Thread starter Giantkiller
- Start date
The problem often with running a water heater as a load is the 4500 watt draw on the inverter (or, at least my issue). Has anyone converted their water heater to lower watt elements? I see they're available in the 1000-1500 watt range. I'm sure the recovery will be longer but for just me and my wife (empty nesters) i don't think it would be an issue.
Zwy
Solar Wizard
A 1500W element will take 3 times as long to fully heat the water back up to temp. The only gain is the lower wattage won't tax the inverters as much. The most I've seen my heat pump water heater use is 400W after it initially runs the 4500W element after initial startup. I've been very impressed with the hybrid heat pump water heater I have. I still have the propane in series after the hybrid, this gives us 100 gallons of stored hot water. This helps if we have a few days in a row of limited sun, I can program the water heater with the phone app to only run certain times or shut it off completely. This helps get thru those days and then can run it when the sun is shining. Don't overlook additional hot water storage if you have the room for another water heater. Laundry is done here on days of good sun so it all plays together nicely.
TM48
New Member
I retrofitted my 5500 watt elements with 3500 watt low density fold back style elements. The water heater is also on a electronic timer so I can control when the load occurs. It now takes about 45 minutes to heat the 50 gallons which runs twice a day. This works for me as I'm a widower and don't have a high HW demand.
I also have a propane WH in series with an electric unit which is plumbed to the desuperheater of a geothermal. (I don't run the propane unit, just use it as a storage vessel for a higher deltaT so the desuperheater is more efficient). This does a pretty good job during winter when the geo is in high demand, not so much during spring-fall. We use around 3.5kw/day heating water during the winter, this goes up to around 6kw/day when the geo isn't in demand. The usage isn't the issue as much as the 4500w load when the unit is calling for heat, which is too much added load to my 6000xp. The idea is to spread the load out during the day.
Is your hybrid WH unit located in a basement? I've considered a hybrid unit, but I'm concerned about the extra cold air that will need to be removed from my finished basement. The WH and solar equipment are in a "mechanical room" in my basement adjacent to the finished area.
Zwy
Solar Wizard
Mine uses around 3 Kwh per day, if I turn it off at night it uses about 2.5 Kwh. If she does multiple loads of laundry and runs dishwasher like yesterday, it used 5.8 Kwh but it ran all day.
It is in my basement. The bonus is it will dehumidify the basement. My basement isn't conditioned or finished. The inverters, battery bank and charge controllers are down there plus one freezer and the propane furnace. I have not noticed any real temp difference. It is open to about 900 to 1000 sq feet.
Finished basement I don't know if I would be concerned about it. There is the option to duct the inlet and outlet air.
