I need help identifying HVAC parts.

[DualFuel]

The junkyard just took in an inventory of HVAC parts from a business that closed. Unfortunately, I do not know what I am looking at.
 I was hoping there would be a part that could be placed in the flow of a hydronics system, that would turn on a switch at a certain temperature. I don't even know the name of such a part, consequently, am not having any luck with Google. I don't have any hydronics books. Would ASHRAE be a good place to start? Dunno?

 I'd like to find a switch that would sit in a solar collector, and upon heating up, turn on a 12volt circulation pump. Please show me where Clueville is!
Thx DF

[rossw]

The junkyard just took in an inventory of HVAC parts from a business that closed. Unfortunately, I do not know what I am looking at.
 I was hoping there would be a part that could be placed in the flow of a hydronics system, that would turn on a switch at a certain temperature. I don't even know the name of such a part, consequently, am not having any luck with Google. I don't have any hydronics books. Would ASHRAE be a good place to start? Dunno?

 I'd like to find a switch that would sit in a solar collector, and upon heating up, turn on a 12volt circulation pump. Please show me where Clueville is!
Thx DF

Like so many things in life, there are a myriad of ways to do this, none necessarily "right" or "wrong".

The general term for the device you want is a thermostat.

There are non-electrical devices that will open a valve at (or about) a nominated temperature and permit water flow - much as the thermostat in your car opens to regulate the engine temperature by letting water out to the radiator once it gets hot enough.

There are thermostats that have sensors IN the water flow (require a break in the pipe to install), and sensors that bolt on the outside of a pipe (more convenient but less accurate). Some are electronic devices (temperature sensing components), some are electromechanical devices (bi-metal strips), and some are basically a liquid-filled tube that operates a bellows to operate a microswitch.

As for your small circulating pump - many people believe a small solar panel just for the pump is a better option - the pump runs only when there's enough solar power to make it worth the effort, and runs harder when there's more solar energy. (I'm not a great proponent of this alternative however, as it doesn't take into account cloud - you could have a very hot collector, then plunge into relative darkness - and with no pump to move the water you have excessive temperature. Similarly, when the sun comes out, the collector may still be cold but the pump is running full bore. It needs to be smarter. I use a differential thermostat on the manifold and inlet)

[ghurd]

"Clueville" may be in reply #26, but the rest is great too.
It is dirt-simple, meaning no bells & whistles.
http://fieldlines.com/board/index.php/topic,136388.0.html
G-

[beyonder]

 You could use an RV water pump, along with an automotive thermostat, positing the t-stat after the RV pump, when it heated up, the t-stat would open reducing the pressure and engaging the pump, it would shut off automatically at night when the tank cooled and the t-stat closed ( increasing pressure making the pump turn off )...It may require tho that you use an open loop system for this approach, if closed it may just pressurize and make the pump shut down.   Also, these pumps are 12volt, they're not cheap tho, they can run between 200 - 300.00 ( here in Canada anyways )...

 If your system is like the other posted in the link there :

 Is this closed loop?  If so you may want to use a fresh water intake and a dump valve ( along with the pressure relief valve ).  A dump valve could be as simple as a car t-stat with a higher setting, just below the steam point, the fresh water fill valve ( a good idea in both closed and open systems, one to relief pressure by cooling down, the other to counteract evaporation ) could be as simple as a fill valve from a toilet ( keeping to simplicity ).  Another option you may want to consider, if this is only going to 1 reservoir or 1 radiator is no pump.  Position your collector lower than the other and let the heat migrate on its own ( at the moment i cant recall the proper term for this lol ).... you could easily make this a 0 energy ( not counting water from the tap ) deal....   just my thought's tho...

 

[kenputer]

Here is a site for DTC that would work for you. http://sites.google.com/site/mydtcstore/home