solar water heater tubing that is sun light rest breaking down

[lcrop1]

I am looking for a black tubing that is sun light restant to make solar water heaters

 

[IRstuff]

But your pipes are going to be insulated, aren't they? So, does it matter what color the pipe is?

TTFN

FAQ731-376

 

[lcrop1]

no they will be in an area that will not freeze

 

[MintJulep]

Copper + black paint.

 

[lcrop1]

have you priced copper lately I am goung to need to covr 400sqft to do the job I will paint if I half to.

 

[willard3]

Unmodified types of plastics that are regarded as having unacceptable resistance to UV are POM (Acetal), PC, ABS and PA6/6. Other plastics such as PET, PP, HDPE, PA12, PA11, PA6, PES,PPO, PBT and PPO are regarded as fair. Note that a PC/ABS alloy is graded as fair.

Have you priced any of these? Copper may be cheap for how well it works.

 

[IRstuff]

Even on just a cold day, you'd probably want insulation on the pipe to lose as little heat as possible.

Frankly, if you're willing to paint the pipe, then insulating is only a minor additional step. This will divorce the pipe material selection from UV resistance.

TTFN

FAQ731-376

 

[lcrop1]

what about heat absorbing if you insulate the pipe you need the pipe to absorb the heat from the sun to heat the water inside right?

 

[IRstuff]

Well, if you read the literature on solar heaters, rarely is the piping itself used as the direct collectors, since their surface geometries are not optimized for collection efficiency.

It's much more efficient in piping to use an efficient collector that's thermally sunk to relatively sparse piping. Particularly since you need about 5 m^2 of collection area to get a reasonable amount of heated water:

capacity = 100 gal/day
effective insolation = 3.3kWh/m^2/day
temp rise = 70ºF

That would be a lot of piping to get the equivalent amount of collection area.


TTFN

FAQ731-376