Side arm question

[Tom Sawyer]

My Portage and Main OWB is finally hooked up and the house is warmer than it has ever been 8).  However, I have a question about how the side arm was installed on my hot water heater.  The guy that installed it (he does this for a living) put the input end of the side arm at the drain of the water heater, and the output end at the hot water output of the water heater.  The problem is this:  when I turn on a hot water tap (or shower ) it runs hot for a short time, but then siphons the cold water from the bottom of the tank instead of taking hot water from the top.  This tends to lower the temperature of the water coming from the tap (and therefore the enjoyment of the shower :().   

As I think about this, I wonder why the output of the side arm can't be connected to the cold water input of the tank, perhaps with a check valve to keep the hot water from moving up the cold water input.  Would the hot water from the top of the side arm flow down the cold water pipe to enter the tank near the bottom?

Any help would be appreciated!

Tom

[Jeff]

This is the way its supposed to be hooked up:

http://crossfirefurnace.com/options.html

You dont draw water out of your water heater any differently then you did, the side arm puts the heat into the heater.  It should still be drawing from the top.

[Tom Sawyer]

Thanks Jeff.  My heater is slightly different than the one in your link.  The pressure valve is also on the top of the tank on mine rather than the side.  I  don't think my heater has any place to connect the side arm to the side.

[Tom Sawyer]

Just to clarify further, on the diagram in your link, my side arm would be connected to the hot water outlet, just under the mixing valve.

[Gary_C]

You are correct. The top connection of the side arm should be connected to the cold water inlet pipe if there is not a third top connection on the water heater.

The only connection to the hot water outlet line should be for a tempering valve to prevent scalding.

The side arm should not be connected to the hot water outlet line.

[Jeff]

They usually hook into the drain on the bottom, then the side arm is fitted with the new drain. That's what you are seeing in that diagram.

[woodmills1]

I have a free heat machine from timber ridge and also their side arm water heater.  It is installed exactly as pictured.  The inlet is at the drain and the outlet is at the overflow valve.  When I bought it they took the specific info from my hot water heater and the side arm was constructed so it fits the heater perfectly.  Also am glad I added the tempering valve as without it we would suffer skin loss.

[BBTom]

The cold water input on every hot water heater I have seen has a dip tube that runs to the bottom of the tank.  Do not hook the outlet of your sidearm to the cold water inlet.  You can however hook the input of your sidearm to the cold water inlet and it should still thermosyphon thru the water heater due to the dip tube.  It works better when hooked to the drain at the bottom of the tank.  

Teeing off of the hot water outlet: If your water heater has the "built-in" check valves. (built into the close nipples on top the tank) it will cause you to pull most of the water from the sidearm and not from the tank, thereby giving you the nice "cool rinse cycle" you are experiencing. If you replace it with a normal nipple, the problem should be better.

I put a tee under the relief valve and hooked in there.  My relief valve is on the top also.  It allows the water to "mix" some before going out the hot water line.  

[Tom Sawyer]

Thanks for the information.  For now I have partially closed the ball valve at the outlet of the side arm to restrict the flow, hopefully causing more hot water to be drawn from the tank.  However, this will also restrict the thermo siphoning effect which means more time needed to heat the incoming cold water.

[Tom Sawyer]

Just a quick update.  After partially closing the ball valve at the top of the side arm my shower stayed hot ( ), and the water seems to be siphoning through the side arm properly, so for now I am going to leave it the way it is.  If I have problems down the road I will change things around. 

By the way, Heatmor also suggests connecting the side arm the way mine is connected (outlet of side arm connected to hot outlet from tank).

Tom

[sawdust]

Dang, here i thought we might be discussing guns.

On a recent call we found a very small perfect condition Derringer!
Actually I don't know what it was. Turn of the century .22 revolver 5 0r 6 inches overall. The trigger folded down. octagonal barrel.

[woodmills1]

side arm    :D :D :D :D

[Tom Sawyer]

Sorry to disappoint you! :D :D

[OneWithWood]

Sawdust, that sounds like a starters revolver.  Is there a vent in the barrel just past the cylinder?

[sawdust]

No vents, this is a lead spitting ladies garter gun.
I am hoping to get a couple pictures before the RCMP destroy it.
Our government treats these guns the same way yours treats marijuana.

[Jeff]

No vents, this is a lead spitting ladies garter gun.
I am hoping to get a couple pictures before the RCMP destroy it.
Our government treats these guns the same way yours treats marijuana.

First come first serve?