solar water heater
Hi all, I bumped into this today. Looks interesting. solar water heater
Forum Discussion
Hi,
Here is a response in regards to freezing from BHA solar:
"Freeze Protection
Our Solar Water Heater Panels are designed to connect directly to your water system, so they contain water. Since they are installed outside they are also subject to freezing temperatures. When the water in the panels freezes it immediately expands by 9%, and if it has nowhere to expand to it will actually stretch and ultimately destroy the tubing in the panels.
If you are using our panels in an area where freezing temperatures are rarely encountered (once a year or less on average) and if you are using PEX tubing to connect the panels to each other there is no need for a freeze protection system. The ice will expand out of the panels and stretch the PEX tubing somewhat.
If you have more frequent freezes one of the following freeze protection systems must be used:
Freeze Valve – A freeze valve is typically installed near the highest point in the solar installation. It is a simple and reliable device that releases small amounts of water when temperatures approach freezing. This way the panels and all the plumbing are kept ice free by allowing warmer water from the inside to slowly flow through the panels.
Drainback Tank – This is a device that is installed inside in the water circuit. When the pump shuts off in the afternoon, the water from the panels and plumbing outside is allowed to drain out, and the outside components fill with air from the drainback tank. This type of system has the advantage of not draining any water, but is more complex and requires a larger capacity pump to re-fill the panels with water when the sun shines again the next morning.
Water Circulating System – In this type of system a very slow circulation of water from inside the building through the panels is maintained during periods of freezing. This solution requires the pump to operate at a reduced speed when freezing conditions are sensed, so a supply of electricity at night is required. Because a failure of this electric supply will cause immediate freezing of the system it is not an approved method of freeze protection.
Manual Drain – You can de-activate the system during the period of frost by manually draining the water out, especially if at your location the freezing period is also mostly cloudy, or if the sun angle is very low, because the
efficiency of the system is low during these conditions anyway."
I've written back to as the price for a drain down system.
BTW I'm harvesting 219 watts @ 1:00 p.m. (16 amps BFL)
Here is a response in regards to freezing from BHA solar:
"Freeze Protection
Our Solar Water Heater Panels are designed to connect directly to your water system, so they contain water. Since they are installed outside they are also subject to freezing temperatures. When the water in the panels freezes it immediately expands by 9%, and if it has nowhere to expand to it will actually stretch and ultimately destroy the tubing in the panels.
If you are using our panels in an area where freezing temperatures are rarely encountered (once a year or less on average) and if you are using PEX tubing to connect the panels to each other there is no need for a freeze protection system. The ice will expand out of the panels and stretch the PEX tubing somewhat.
If you have more frequent freezes one of the following freeze protection systems must be used:
Freeze Valve – A freeze valve is typically installed near the highest point in the solar installation. It is a simple and reliable device that releases small amounts of water when temperatures approach freezing. This way the panels and all the plumbing are kept ice free by allowing warmer water from the inside to slowly flow through the panels.
Drainback Tank – This is a device that is installed inside in the water circuit. When the pump shuts off in the afternoon, the water from the panels and plumbing outside is allowed to drain out, and the outside components fill with air from the drainback tank. This type of system has the advantage of not draining any water, but is more complex and requires a larger capacity pump to re-fill the panels with water when the sun shines again the next morning.
Water Circulating System – In this type of system a very slow circulation of water from inside the building through the panels is maintained during periods of freezing. This solution requires the pump to operate at a reduced speed when freezing conditions are sensed, so a supply of electricity at night is required. Because a failure of this electric supply will cause immediate freezing of the system it is not an approved method of freeze protection.
Manual Drain – You can de-activate the system during the period of frost by manually draining the water out, especially if at your location the freezing period is also mostly cloudy, or if the sun angle is very low, because the
efficiency of the system is low during these conditions anyway."
I've written back to as the price for a drain down system.
BTW I'm harvesting 219 watts @ 1:00 p.m. (16 amps BFL)
