My $125 solar hot water heater (StarPak Solar Systems)

[simplemanlance]

For a while now ive been wanting to build a solar hot water heater like gary's $1k drainback SHW system. extra funds have really been whats holding me back.  i turned to craigslist to try to some used panels, pumps or anything that might help save some cost on the build. after a long search i finally came across something good. well what i think is good.

its a Starpak Solar Systems solar hot water heating system. this company was out of Novi MI from 1975 to the mid 1980's some time.  Novi is 20 minutes from my house so i thought that was kinda neat that these were made local.  I tried to google them but came back with nothing useful.  Anyways the stuff i bought off craigslist came with 2 4x8 panels, 2 pumps(one has the controls on it), 80 gal storage tank, furnace chimney heater, a coil that goes in the cold air return of your furnace, and most important the original instructions.  the date on the panels say 1983 that a year older them me   the guy i bought them from said everything works and the only reason they were taken down was that the roof was getting replaced and he didnt want to put them back up.  i will post up some pictures shortly along with some more info.

[simplemanlance]

sorry for the delay on the pictures, weather was nice this weekend so i spent my time outside cutting and splitting wood.   here are the pictures.






i plan on pulling apart the panels this winter and making sure the insulation is still good and just checking out whats inside.  I'm also not sure if i want to hook it up like it was intended too or if i want t make a true drain back. this kit is a drain back but when it drains back it drains right into a drain so in the spring/fall when the the nights get cold i will be wasting a lot of water at night because it drains the panels so they don't freeze.

[huntedheads]

Looks like four fittings on the top? maybe just something sitting there but some of the lochinvar tanks had a stainless steel heating coil built it but the ones I've seen had the fittings for the internal coil on the front. Good buy any way! I am going to pick up a Lochinvar 119 gallon tank for my solar heating in the morning, the old tank has sprung a leak. Google the model number might want to make it a closed loop in Michigan if it has an internal coil.

[MattM]

What do you mean it drains back to a drain?  Is the tank not designed to store the heat?

[GaryGary]

Hi,
Nice buy!

I sounds like it might be a drain down system rather than a drain back system.

The drain down systems used a valve to drain water from the collector if the temperature drops down near freezing.  They were intended to provide some freeze protection for areas that don't get much freezing weather.  The water drained from the collector just went right down the drain (or on the ground). 
A true drain back system drains the collector water back into an unpressurized tank every time the pump turns off.

I'm wondering if this is not the type of system in which the potable water from the hot water tank is circulated through the collector and then back into the tank?
In other words, there would be no heat exchanger to transfer heat from antifreeze that is circulating through the collectors to the potable water in the hot water tank.

Any chance we could get a bigger picture of the instructions sheet?  I can't quite read it.

The drain down systems did not have a very good reputation for reliability in that if the drain down valve fails, the water in the collector freezes and this can easily burst the collector tubing.  I'd try to do a check to make sure that has not happened to your collector.



Gary

[huntedheads]

Your rite Gary in the bottom rite of the instructions is says whenever the collector temp drops below 50 degrees the controller auto drains the collector.

[simplemanlance]

yes Gary you are right on both things. it is a drain back system and it does circulate potable water through the collectors.

i havent had a chance to do anything with these parts yet. Im still unsure as to where im going to mount these collectors. The plan was to mount them on the roof of my shed (45* angle)  but it does get shaded by a huge wallnut tree from like 2pm on. i was also thinking of making it a true drain back system with a big storage tank so i could try and take full advantage off the sun i will get. However i did get 13 new energy star windows on my first floor, and i can already feel a huge difference over the 85 year old single pane windows i had before.

 

Hi,
Nice buy!

I sounds like it might be a drain down system rather than a drain back system.

The drain down systems used a valve to drain water from the collector if the temperature drops down near freezing.  They were intended to provide some freeze protection for areas that don't get much freezing weather.  The water drained from the collector just went right down the drain (or on the ground). 
A true drain back system drains the collector water back into an unpressurized tank every time the pump turns off.

I'm wondering if this is not the type of system in which the potable water from the hot water tank is circulated through the collector and then back into the tank?
In other words, there would be no heat exchanger to transfer heat from antifreeze that is circulating through the collectors to the potable water in the hot water tank.

Any chance we could get a bigger picture of the instructions sheet?  I can't quite read it.
 

[GaryGary]

Hi,
I'd suggest you run this Solar Site Survey:
http://www.builditsolar.com/SiteSurvey/site_survey.htm
Figuring out shading for the full year by eyeball can lead to some big mistakes -- the site survey is an easy way to get it right.
Only takes about an hour and its FREE

Gary

[tomtank]

The Star Pak system had a very nice collector. The thermal performance was very impressive. You did very well!