Guidance on swivel fittings for heater tank nipples

[Sarg]

Getting together items needed to install a new water heater.
I intend to use 3/4 swivel elbows for the water connections and have questions on the proper technique to tighten them when they have a rubber sealing grommet or washer as pictured.
Is it hand tight and then 1/2 a turn or should they be tighter ? Would a thread sealant be beneficial to lube the threads ?

 

[Phog]

You're overthinking it. Tighten it until it stops leaking, and you're done. No thread sealant needed & in fact if you use sealant, it has a small chance of interfering with the rubber washer sealing. (But 99% it will still be fine either way).

 

[Sponsor]

 

[Reach4]

You can use silicone grease on both the rubber and the threads. On the rubber, it helps the rubber adjust into the space, and on the threads makes for less turning torque required. Thread sealant could work too. I am not a pro.

 

[Sarg]

You're overthinking it. Tighten it until it stops leaking, and you're done. No thread sealant needed & in fact if you use sealant, it has a small chance of interfering with the rubber washer sealing. (But 99% it will still be fine either way).

I agree ... I "overthink" everything when it comes to plumbing.
This installation is in a mobile home and the heater and pressure tank are stacked within the wall. So any maintenance involves emptying a large sideboard ... moving furniture ... removing a 4 x 8 panel and the wife is not thrilled when we have to go through the chore.

I've recently had pump cycling issues and discovered the pressure in the supply tank was very low ... so I upped that to 3 lbs. below the low setting on the 30/50 switch. I've been adjusting the switch so the pump would consistently start ............ AND now I just noticed the ceiling adjustment on the square D ( The smaller one ) The adjustment nut is totally off the spring ..... Time for more research.

 

[Phog]

If you snug up the fitting to where it's not leaking during install, that should be good enough where you'll never have a problem. It will probably take a more than 1/2 turn past hand tight. But you'll know it visually (by not seeing any water weep out with the pressure on), and once it's sealed, it's sealed. And should remain so indefinitely.

 

[Reach4]

The adjustment nut is totally off the spring ..... Time for more research.

If you are talking about the nut on the small spring, that is not really a problem. To get the 20 psi differential, that spring is often not compressed much, and the difference with not-at-all compression might typically be an 18 psi differential.

Pressure tanks can go bad. Fairly predictable that they will fail with time and use. A good tank will typically be able to supply about 1/4 of the nominal tank size in water. For example, a 32 gallon tank may be able to supply about 8 gallons during a test. Let the pump run until the pump shuts off while not using more water. Turn off the pump. Measure how much water you can get out. You can use a 5 gallon bucket as a measure.

A mobile home might only have a 20 gallon tank.

 

[Sarg]

If you are talking about the nut on the small spring, that is not really a problem. To get the 20 psi differential, that spring is often not compressed much, and the difference with not-at-all compression might typically be an 18 psi differential.

Pressure tanks can go bad. Fairly predictable that they will fail with time and use.

My concern is the range is OK .... starts at 30 ( my fiberglass pressure tank is at 27 ) but the upper shut off is a little above 60 and the nut is totally off the adjustment spring ( I must have done it trying to get the cut-off down. I've got the crappy Poly-B piping and I doubt any extra pressure is beneficial.

 

[Reach4]

My concern is the range is OK .... starts at 30 ( my fiberglass pressure tank is at 27 ) but the upper shut off is a little above 60 and the nut is totally off the adjustment spring ( I must have done it trying to get the cut-off down. I've got the crappy Poly-B piping and I doubt any extra pressure is beneficial.

Pressure switch is bad. Adjustment will not reduce the current 30 psi differential, since the loose spring is the best you can do to lower differential.

If your pressure tank is Wellmate, those are prone to failing earlier than other tanks. Those have a bladder, and the better tanks have diaphragms.

The Flexcon fiberglass pressure tanks are good, but you are not likely to have a premium tank installed OEM.

 

[Sarg]

Just a closing post & update. I have replaced the Square D switch and the new one is functioning as it should. I will not be messing with the adjustments as I'm sure I caused my own problems with the old one. Only existing issue with the 2006 installation is that there now is a minor leak at the cold water entry nipple to the heater ( at the base ) that is easily removed with a small cloth periodically.
The new Rheem 30 gal. heater and Dayton 20 gal. steel tank are in the garage ... on stand-by ... waiting for a couple more components due in the mail today. I've attached a picture to show the mess I created in 2006. I've realized that the replacement will involve rebuilding the shelf structure .... removing the full cut 2 x 2 support legs with 1" or 5/4 lumber to make room for the larger diameter tank (17.5" versus the new 20" diameter ). The opening now is right at 20" . Created my own problems and realize it 14 years later.
And now the big decision is to do the replacement this year before the freezing weather hits .... or live with what we have until spring. With my level of "expertise" I'm planning on a day or 1 1/2 days to get it done.