[Pops]

Tempering valve:
http://www.watts.com/pages/learnAbout/t ... asp?catId=

[vtsnowedin]

$this->bbcode_second_pass_quote('Ibon', '
')
Most of the pressure relief valves I am seeing on line are rated for 150psi and 210 degree F. Does this mean that the valve only opens at this psi and temp range when the water would actually start boiling? If so is this the right one for this system?

[Pops]

$this->bbcode_second_pass_quote('vtsnowedin', '')$this->bbcode_second_pass_quote('Pops', 'T')hanks VT, I was afraid of that

I made a tank for the greenhouse out of a series of 55gal plastic drum and had to order some fittings to go through the sides of the tank, I assume you can make it work through sheeting

http://www.mcmaster.com/#tank-fittings/=sbh92x

[vtsnowedin]

$this->bbcode_second_pass_quote('Pops', '[')
Or take out only the top element and plumb your collector hot return into that fitting and come off the drain valve at the bottom to supply to the collector. That gives you insulated, thermostated, electric back-up heated solar hot water.

[Ibon]

$this->bbcode_second_pass_quote('Pops', '
')Or take out only the top element and plumb your collector hot return into that fitting and come off the drain valve at the bottom to supply to the collector. That gives you insulated, thermostated, electric back-up heated solar hot water.

[Ibon]

I got this from a site on the diameter of the thread on electric hot water tanks that the elements get screwed into.

The thread is a 1" (diameter) x 11-1/2 NPSM thread and is standard for all residential water heaters that use screw-in elements.

In Panama I have problems finding fittings so I want to get this before I leave in a couple of weeks. I need the fittings to adapt 3/4 inch CPVC pipe into this thread. Where do I find this? Any ideas?

[Newfie]

Try grainger

http://www.grainger.com/product/EATON-M ... pp%3Dfalse

Or Eaton
http://www.eaton.com/Eaton/ProductsServ ... 259#tabs-1

Or Parker hydraulics
http://ph.parker.com/us/en/fittings

[vtsnowedin]

$this->bbcode_second_pass_quote('Ibon', '')$this->bbcode_second_pass_quote('Pops', '
')Or take out only the top element and plumb your collector hot return into that fitting and come off the drain valve at the bottom to supply to the collector. That gives you insulated, thermostated, electric back-up heated solar hot water.

[vtsnowedin]

I'll bet that cruse ship designers have a set of tables that show how much hot water they need when all 3000 passengers come back from their day on shore. It shouldn't be too big a secret.

[Ibon]

$this->bbcode_second_pass_quote('Newfie', 'T')ry grainger

http://www.grainger.com/product/EATON-M ... pp%3Dfalse

Or Eaton
http://www.eaton.com/Eaton/ProductsServ ... 259#tabs-1

Or Parker hydraulics
http://ph.parker.com/us/en/fittings

[Pops]

NPSM have the same thread pitch as NPT but are straight whereas pipe threads are tapered. The fitting you need will have an O ring, like a hydraulic hose to make a seal. It's called ORB for O Ring Boss.

[Ibon]

$this->bbcode_second_pass_quote('Pops', 'N')PSM have the same thread pitch as NPT but are straight whereas pipe threads are tapered. The fitting you need will have an O ring, like a hydraulic hose to make a seal. It's called ORB for O Ring Boss.

[Pops]

How about this page
http://www.discounthydraulichose.com/product_p/6405.htm

this item
6405-16-12 | #16 SAE/ORB Male x 3/4" NPTF Female

then just straight npt union?

I think that's right, worth a call.

[Pops]

And if That doesn't work, get Newfie's fitting, a short straight pipe nipple and an O ring; thread the straight pipe into the Female fitting, put the O ring on the pipe and tighten 'er down on the water heater.

[Pops]

Just for those observing, NPT is National Pipe Thread and it is how all domestic plumbing is threaded, the male and female are tapered (male is smaller diam at the end and larger diam toward the pipe) so that as you tighten them the threads deform and that makes them watertight.

Straight pipe looks the same as NPT but there is no taper, so just like a nut and bolt you can keep turning forever and until they come up against a stop (the head of the bolt for example) they never tighten. Straight pipe uses a washer or O ring to make the seal.

Usually high pressure systems i.e., steam and hydraulics don't use NPT because to be able to deform the pipe must be soft ("lead" pipe) and being soft, it can strip out under pressure. Straight pipe doesn't need to deform to make a seal so the material can be harder and the connection stronger.

Probably the reason straight to npt adapters are rare is to keep people like me from blowing their fool heads off cobbling up some galvanized pipe in a 2,000psi hydraulic system - which btw I've seen but not been guilty of personally.


ETA, too bad Patience isn't around much, he knows all this stuff.

[MD]

you need a cheap frequency drive connected to a small 3 phase circulating pump motor with a feedback loop from an analog temperature sensor that is positioned at the hottest part of the loop.

less than $400 for the components.

[Scrub Puller]

Yair . . . bloody hell fellers, I don't believe this conversation.

The fitting is called a "bush" threaded externally (male) 1" NPT (or BSP) and internally (female) 3/4" NPT (or BSP) . . . just glue a male adapter onto the PVC and you are in business . . . put 1" NPT x 3/4" NPT bush into Google images and thousands are shown.

Or am I missing something?

Cheers.

[vtsnowedin]

$this->bbcode_second_pass_quote('MD', 'y')ou need a cheap frequency drive connected to a small 3 phase circulating pump motor with a feedback loop from an analog temperature sensor that is positioned at the hottest part of the loop.

less than $400 for the components.

[vtsnowedin]

$this->bbcode_second_pass_quote('Scrub Puller', 'Y')air . . . bloody hell fellers, I don't believe this conversation.

The fitting is called a "bush" threaded externally (male) 1" NPT (or BSP) and internally (female) 3/4" NPT (or BSP) . . . just glue a male adapter onto the PVC and you are in business . . . put 1" NPT x 3/4" NPT bush into Google images and thousands are shown.

Or am I missing something?

Cheers.

[Pops]

$this->bbcode_second_pass_quote('Scrub Puller', 'p')ut 1" NPT x 3/4" NPT bush into Google images and thousands are shown.

Or am I missing something?

Cheers.