best type of water system flat, tube, tank in or outside?

[inetdog]

But then how does the seal work in the tank where the copper rods fit into? Is that a special seal?

Are you talking about the heater tank? No copper rods there.
Or are you talking about the manifold (large diameter tube at the top of the panel where the heat pipes screw in? At that point it is just a standard pipe thread seal AFAIK. At the top of the tube, the heat pipe is thermally connected to a solid piece of metal that screws into the manifold.

[Naptown]

Are you talking about the heater tank? No copper rods there.
Or are you talking about the manifold (large diameter tube at the top of the panel where the heat pipes screw in? At that point it is just a standard pipe thread seal AFAIK. At the top of the tube, the heat pipe is thermally connected to a solid piece of metal that screws into the manifold.

Actually most are immersion wells such as used for an aquastat etc and are brazed into the manifold. The heap pipe slips into that with a heat transfer grease.

[rainworm]

controller

What type of controller is needed with this system? I see this one. solar water heater controller SR609C for compact pressurized solar water heates with electric element. Why would they do electric element? Is that the right type of controller?

[inetdog]

What type of controller is needed with this system? I see this one. solar water heater controller SR609C for compact pressurized solar water heates with electric element. Why would they do electric element? Is that the right type of controller?

Many solar tanks for on-grid systems contain an electric element to be used when the solar heat is insufficient. To get the maximum benefit from solar heating the controller has to be able to selectively shut off the electric element so that all of the heat comes from the panels, just slower.

[russ]

Many solar tanks for on-grid systems contain an electric element to be used when the solar heat is insufficient. To get the maximum benefit from solar heating the controller has to be able to selectively shut off the electric element so that all of the heat comes from the panels, just slower.

My tank does - Especially in the winter time during stormy periods it is used - either that or have 80° F water

[cssolar]

controller

What type of controller is needed with this system? I see this one. solar water heater controller SR609C for compact pressurized solar water heates with electric element. Why would they do electric element? Is that the right type of controller?

Hi Rainworm

The typical Chinese swh controller you are looking at, is for a high pressure heatpipe swh ( can also be used in a pre heat type swh )

It consists of a sensor you fit in the swh tank and a control panel ,

It can be used for 2 things

1 , Just to show the water temp in the solar tank

2 , To maintain the water at a pre set temperature by automatically turning on and off a heating element in the tank,

there are normally several programming options ie, maintain a minimum tank temp or combination of timer and min tank temp

Most also have a manual override , so you can just fire up the element until it reaches the pre set max temp and shuts down.

Also available are low pressure controllers ( have one on my own system ) they have the same features as above but also have a water level sensor and controlled electro filling valve.

Which is great if the weather is poor as the solar tank will not fill to the next stage unless the water temp reaches 65 degrees Celsius ( 4 filling levels quarter full to full ) it will also start to fill the tank if the water level drops to just before empty ! and give a low water level audible warning telling you to get out of the shower quick !!


If you are building a split system I guess a differential controller may be best as it has 2 sensors which will tell your circulating pump when to fire up.

Tony

[rainworm]

thanks

Thank you for the clear explenation, this helped a lot.

[mocapetan]

Hear exchanger

Mocapetan from sunshine state.
Just looking for an inexpensive way to raise temp in tank of water to evap. I have a pretty good atmospheric evaporator that gets rid of 12 to 15 gals. a day. I've read that by raising temp. of waste water in tank by as little as 10 degrees, increase rate of evaporation immensly.
I have 500 ft. of black 1/2 " pvc pipe and a huge flat foof. I might even have 800 or more of 3/4".
Any help on heat exchange, flow rate, pipe size, is appreciated. It sounds quite simple, but i'm a little in the shade.

[inetdog]

Mocapetan from sunshine state.
Just looking for an inexpensive way to raise temp in tank of water to evap. I have a pretty good atmospheric evaporator that gets rid of 12 to 15 gals. a day. I've read that by raising temp. of waste water in tank by as little as 10 degrees, increase rate of evaporation immensly.
I have 500 ft. of black 1/2 " pvc pipe and a huge flat foof. I might even have 800 or more of 3/4".
Any help on heat exchange, flow rate, pipe size, is appreciated. It sounds quite simple, but i'm a little in the shade.

IF the water you are trying to evaporate does not contain corrosive chemicals, and you do not have a need to withstand freezing temperatures, then a simple loop of pipe with a convection circulation (lots of parallel runs with a manifold at each end rather than one long run) may not even need a pump.
To reduce the energy needed to pump the water, again keep the length of the individual 1/2" or 3/4" pipes small. Put many in parallel instead.

Why are you evaporating this water?

[russ]

If you are trying to evaporate the water because it is contaminated - some significant part of the contamination will come out in your system - open trays might be better.

[mocapetan]

IF the water you are trying to evaporate does not contain corrosive chemicals, and you do not have a need to withstand freezing temperatures, then a simple loop of pipe with a convection circulation (lots of parallel runs with a manifold at each end rather than one long run) may not even need a pump.
To reduce the energy needed to pump the water, again keep the length of the individual 1/2" or 3/4" pipes small. Put many in parallel instead.

Why are you evaporating this water?

Again i'll emphisize there is nothing hazardous in this liquid.There is a small amount of a colored floresent penetrent we use for nondestructive testing of parts that we weld and inspect for any cracks that may develop from welding.The remaing liquid in this tank is just water needed to flow thru our machines for coolent. The EPA rules that any liquid uesd in industrial processes, including water, must be disposed of per fed./stste regulations, and atmospheric evaporation meets there standards.
Periodically, between a year and 18 months, we clean out our tank. There is generaly a55 gal. drum of non-hazardous sludge the we have a reputable disposal company pick up and dispose of.
Now back to some ideas of solar--I really do not want to pump this fluid on to the roof for obvious pipe leakage/burst, anything like that, I would like to just use water on the roof and a heat exchanger in or near my tank to avoid any possible accidents.
I thought some slow gpm flow thru some 1/2" pvc pipe or 3/4", if more heat was produced by a bigger size,run it thu a little water to water heat exchanger, and it could raise my tank temp. by ,say, maybe 10 degrees.That would make a huge increase rate of evaporation.

[inetdog]

I thought some slow gpm flow thru some 1/2" pvc pipe or 3/4", if more heat was produced by a bigger size,run it thu a little water to water heat exchanger, and it could raise my tank temp. by ,say, maybe 10 degrees.That would make a huge increase rate of evaporation.

Sounds like the right way to go and potentially will save you from going to a larger evaporator as you grow!

If you are worried about freezing, you will need to use glycol in the roof loop or else use a drainback system. You will want to have a thermostat in the system to prevent the roof loop from cooling the evaporator instead of heating it if the weather turns cool, or at night when the roof loop will radiate heat to the sky and go below air temperature.
Putting the collector on a flat roof may give you even more solar heating because of the air heated by the surrounding roof.
Just painting the evaporator black may help too.

[Naptown]

Again i'll emphisize there is nothing hazardous in this liquid.There is a small amount of a colored floresent penetrent we use for nondestructive testing of parts that we weld and inspect for any cracks that may develop from welding.The remaing liquid in this tank is just water needed to flow thru our machines for coolent. The EPA rules that any liquid uesd in industrial processes, including water, must be disposed of per fed./stste regulations, and atmospheric evaporation meets there standards.
Periodically, between a year and 18 months, we clean out our tank. There is generaly a55 gal. drum of non-hazardous sludge the we have a reputable disposal company pick up and dispose of.
Now back to some ideas of solar--I really do not want to pump this fluid on to the roof for obvious pipe leakage/burst, anything like that, I would like to just use water on the roof and a heat exchanger in or near my tank to avoid any possible accidents.
I thought some slow gpm flow thru some 1/2" pvc pipe or 3/4", if more heat was produced by a bigger size,run it thu a little water to water heat exchanger, and it could raise my tank temp. by ,say, maybe 10 degrees.That would make a huge increase rate of evaporation.

Probably the easiest way to do this is to put a heat exchanger in the tank (think coil of copper tubing) Pipe to the roof to the "collector" and back Insert pump. fil.l drain. and check valves. expansion tank, and add a controller fill with a glycol solution (Think RV antifreeze if just plastic tubing on the roof)