Dip Tube in storage

[eriesigtau]

I have a 500 gal propane tank with two 3/4" fittings (1 of which is a dip tube), one 1" fitting, and two 1-1/4 fittings on the top of the tank. There is also one 1-1/4 fitting on the bottom of the tank. If I need two supplys and 2 returns, how should I utilize these fittings the best way? I would asume I will use the fitting at the bottom of the tank as a drain. Any input would be appeciated.

 

[Piker]

I have a 500 gal propane tank with two 3/4" fittings (1 of which is a dip tube), one 1" fitting, and two 1-1/4 fittings on the top of the tank. There is also one 1-1/4 fitting on the bottom of the tank. If I need two supplys and 2 returns, how should I utilize these fittings the best way? I would asume I will use the fitting at the bottom of the tank as a drain. Any input would be appeciated.

I had similar fittings on my propane tanks... i didn't use any of them except for a 3/4" fitting for a dry well that houses the temperature sensors. I used a standard hole saw to cut holes for 1 1/4" black pipe that was then welded to the tanks. The supply was just a 4" nipple welded flush with the inside of the top of the tank... and each return was a dip tube at the opposite end of the tank that dropped to within a few inches of the bottom of the tank. It's a good idea, especially if your tanks are horizontal, to have the supply as far away from the return as possible to help prevent cross currents that bypass the water volume in the tanks and travel directly from supply to return.

cheers

 

[stee6043]

Since I didn't have access to (nor did I want to pay for) welding I used my top fittings exclusively to plumb my 500 gallon tanks. I rigged up 1" copper pipes to drop through one of my 1-1/4" openings and affixed them with JB Weld to the inside of a 3" nipple. They reach to within 3-4" of the bottom. Works great for the return. I used 1-1/4" lines straight off the top for supply. No welding, no cutting, works great. I used my 1" openings for vents and for filling...

 

[btuser]

Do you need two supply/return sets of equal btu volume, or is one set for heating and the other for DWH. If that's the case I would imagine the two 3/4" fittings would be enough for the DHW, maybe use the in-place dip tube to provide return. Its my understanding when using for DHW you want to draw off the top for hot water and return to the bottom with the mimimal amount of mixing.

 

[in hot water]

DP

 

[in hot water]

you can tee together several small connections if you need handle larger flow rates. I paired the two 3/4" into one 1" for good flow.

I also turned the level gauge (4 bolt) opening into a 1" connection by welding a 1" nipple onto a piece of 3/8" plate, made a gasket and bolted it onto that connection. Save the gasket that fits into the recess if possible then build a flat gasket to fit over the 4 bolt holes, for double gasket surface.

If you have a large bottom opening it can serve as multiple returns and a drain port with a couple tees combined.

It's good that you caught that the one top connection does have a dip tube to the bottom. It is easy to assume it is a top of the tank connection.

A float type air vent is another good idea at the highest connection on the top of the tank. Install a tee with a 6" nipple pointing up and put the air vent there. That way you always, and automatically "burp" the air bubble that traps in the top of the tank.

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