[dumbengineer]

my double water heater tank is at the attic of my house (see pic). i've read instructions how to drain water heater tank but it's for single tank.

what different thing i should take note if i have double water heater tank to drain.

 

[joecaption]

Why are you draining them, replacement, just drain the sediment out?
Draining two of them is no differant then drain one, just have to do it twice.
Shut incoming water off shut gas off, open facuet to relieve pressure, open drain and flip up the pop off valve so it will come out faster.

 

[Bondo]

Why are you draining them, replacement, just drain the sediment out?
Draining two of them is no differant then drain one, just have to do it twice.
Shut incoming water off shut gas off, open facuet to relieve pressure, open drain and flip up the pop off valve so it will come out faster.

Ayuh,.... either Times 2, or run 2 drains hoses, 'n do 'em at the same time...

 

[jagans]

There should be a little panel near the bottom with a typical hose bib behind there. I dont see any in this illustration.

 

[dumbengineer]

if you open faucet will it still relieve pressure if only tank1 is being drained while tank2 is still in service?

if you noticed the hot water pipe from the tanks will combine and become one.

also if i drain tank1 first, will tank2 hot water go to tank1 during draining coz the pipes are tied-in together?

 

[Bondo]

if you open faucet will it still relieve pressure if only tank1 is being drained while tank2 is still in service?

if you noticed the hot water pipe from the tanks will combine and become one.(you need isolation valves, Here)

also if i drain tank1 first, will tank2 hot water go to tank1 during draining coz the pipes are tied-in together?

Ayuh,... In yer drawin', you don't have enough valving in the Hot side to take 1 outa service, 'n run only 1...

 

[dumbengineer]

Ayuh,... In yer drawin', you don't have enough valving in the Hot side to take 1 outa service, 'n run only 1...

so how do i drain this now if the 2 tanks dont have dont have isolation valve?

 

[joecaption]

If both cold water valves are off and your draining both tanks what differance does it make?
Water heaters in the attic are in the the worst possible place possible.
One falure and it could cause thousands on dollars in damage.

 

[ben's plumbing]

for what you are asking you need more service valves .....can't drain just one and leave other in service....ben sr

 

[Bondo]

so how do i drain this now if the 2 tanks dont have dont have isolation valve?

Ayuh,.... As I said, ya Can't do what yer askin' to do....

Hire a Plumber to fix it, so's ya can...
Or,...
Do it Yerself...

 

[plummen]

Around here we're not allowed to put shutoffs on hot side of heater.
If youre only trying to drain one tank the other tank shouldnt really matter as long as cold water is turned off to both.
If it did manage to create enough of a backflow to suck the other heater dry youd just have to wait a few more minutes for it to quite draining,or you could just open the pop off on the heater when it started to happen to break the vacuam

 

[jagans]

1. Fill one Bathtub with water and plug. Leave Bucket for flush.
2. Hook Hoses up to the drain valves and run into the sump pump.
3. Shut off HWH's
4. Shut off the water main.
5. Open the drain valves, and open all the fixtures above, and flush all toilets.
Also open laundry fixture in basement if you have one.
6. Cut cold in pipes about 14 to 16 inches above both HWH's and install Ball valves. Put one on the hot side too if you want isolation. Put wet rag on tie in tho HWH if you sweat.
7. Close all fixtures.
8. Open water main and flush HWH's to sump with installed valves till water runs clear.
9. Fill tanks and flush to laundry two handle fixture with aerator removed.
10. Crack Open fixtures and bleed off pressure.
11. Turn Water Heaters on.