Hot water heater not working well after draining

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JWblue

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Plumber came to drain the hot water heater.

Now we barely get hot water.
 

Snoonyb

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Gas, elec.?

Why did you think it need to be drained?
 

Snoonyb

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What is the setting on the temperature control. It should be slightly on the hot side and there is the possibility that it was turned to it's lowest setting while being drained, and they didn't stick around thinking that you would reset it to you comfort level.
 

JWblue

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What is the setting on the temperature control. It should be slightly on the hot side and there is the possibility that it was turned to it's lowest setting while being drained, and they didn't stick around thinking that you would reset it to you comfort level.
I could swear it was on the "Low" setting before the plumber came but not sure that makes sense. Plumber said he didn't touch the dial which I do not know if is true or not. It was on "Low" when he left.

Turned it up to "A" this morning. Had no hot water for a morning and afternoon shower. Just turned it up to "B".
 

Jeff Handy

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Is there a recirculation line and pump on your hot water line?

Also, some water heaters only have a shutoff valve on the incoming cold line, others also have one on the outgoing hot line.

Make sure these are both fully open.

When you open a hot water faucet all the way, do you soon hear the main gas burner ignite?

You might be only getting a tiny amount of heating from the pilot flame, if yours has a pilot.

Post some pics of the gas valve.
 

JWblue

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Is there a recirculation line and pump on your hot water line?

Also, some water heaters only have a shutoff valve on the incoming cold line, others also have one on the outgoing hot line.

Make sure these are both fully open.

When you open a hot water faucet all the way, do you soon hear the main gas burner ignite?

You might be only getting a tiny amount of heating from the pilot flame, if yours has a pilot.

Post some pics of the gas valve.
Pictures attached.

I was not clear. When taking a shower and turning on faucets we are getting minimal hot water as opposed to none. Certainly not like it was before the draining.

When opening a hot water faucet all the way the main burner does not ignite.

It has a pilot light which I have a question regarding. The gas dial has three settings. "Off", "Pilot", and "On". If I change the setting on the gas dial to "Pilot" does that turn off the gas to water heater or does the setting need to be to "Off" to do that?

Is it important to turn the gas off before draining the water heater? What are the consequences of not doing this? I asked the plumber to do it and he insisted it is not necessary.

Rheem Model SG40T12AVG00


IMG-1699.JPGIMG-1700.JPG
 

Jeff Handy

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Gas valve setting on PILOT does not turn gas off, but it is only on that setting while lighting the pilot.
After holding in the dial and lighting the pilot and waiting one minute, the dial is turned to ON.
This allows the thermocouple to heat up, which keeps the pilot on.

Gas does not need turning off during draining, as long as incoming cold line is left open, and house main water line is left on.

Your pictures are not very helpful.
Pull back farther, take more pics, up down and all around, show any valves within ten feet of the heater, maintain a wider angle of view to give people more perspective.

Post a pic of the gas valve as it currently is, while you are getting only weak warm water, BEFORE you start trying to adjust it.
 

JWblue

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There are not any valves within ten feet of the water heater besides what is in pictures.

Can increasing the pressure on the gas valve improve performance of the water heater?

IMG-1706.JPGIMG-1707.JPGIMG-1705.JPG
 

Jeff Handy

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You would never adjust the gas pressure on the valve.

Meanwhile, I requested a pic of the gas valve, still waiting.
I can’t see it clearly in your pic.
 

Jeff Handy

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I see a valve on the right hand insulated pipe on top of the heater.
Is that the incoming cold?

Your pics don’t show all of the left hand pipe.
Is there a valve on that left hand pipe or not?
 

Jeff Handy

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If all else fails, call the plumber who did your flush.

Explain that you had good hot water until he flushed the tank, now you don’t, he needs to fix whatever he changed or broke.
 

Jeff Handy

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Whenever I do a flush, I know the heater is working well, because it is now full of fresh cold water, and the burner is roaring away trying to heat all that cold water.
 

JWblue

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You would never adjust the gas pressure on the valve.

Meanwhile, I requested a pic of the gas valve, still waiting.
I can’t see it clearly in your pic.
This is the picture of the gas valve on the water heater.

IMG-1708.JPG






I see a valve on the right hand insulated pipe on top of the heater.
Is that the incoming cold?

Your pics don’t show all of the left hand pipe.
Is there a valve on that left hand pipe or not?
There is not a valve on the left hand pipe. I am pretty sure the one on the right is incoming cold.
 

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Jeff Handy

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Take a picture of the gas valve that I can read the settings and see everything clearly.

Your shot is blurry and too off to the side.

By gas valve, I mean the water heater thermostatic gas valve, not the gas shutoff valve.
My fault for not being specific.
 

JWblue

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The plumber also installed a new rotatable exhaust pipe that connects to the straight pipe. Does that look ok? I do not want exhaust fumes in our home.

IMG-1709.JPG

I guess this is the thermostatic gas valve. There isn't anything else with settings.

IMG-1710.JPG


This is the second straight time a plumber drained the water heater and we did not have hot water after he left. FML.
 

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Jeff Handy

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The new exhaust pipe is basically ok.

The upper ribbed end should really be INSIDE the older pipe above it, but the seal looks fairly tight as is.
EDIT, it is INSIDE the upper pipe, but not inserted far enough.

Another poorly framed picture, I can’t see the position of the button where it says PILOT.
The temperature setting is ok.

At this point, you should be calling the plumber to come back and clean up his mess.

EDIT, Your pics are good enough, I did not give precise directions of what I needed to see.
 
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JWblue

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Another poorly framed picture, I can’t see the position of the button where it says PILOT.
The temperature setting is ok.
Does the gas setting look ok? It is set to "On". What is the green button to the right?

I will call the plumbing company tomorrow.

IMG-1711.JPG
 

Jeff Handy

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It looks good.

Maybe the pilot is not lit?

Do you know how to light it?

The green button is pressed to make a spark that lights the pilot.

There is a procedure printed on the water heater.

In short:
Rotate the knob with the arrow back to the middle Pilot setting.
Push it down and hold it.
After a few seconds, push the green button a few times, which should light the pilot flame.
Keep holding the top black knob down for one minute.
Then let the button come back up, and rotate it to ON.
The main burner should come on.

You can lift off the little metal cover door just under the thermostat before you do this, so you can see if the pilot flame is lighting, and you will see the big burner come on.

Put the door back on if all is well.

If any of this confuses or scares you, let someone do it who has experience with it.
 

slownsteady

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It probably wasn't the draining of the tank that causing problems but rather something that may have been bumped in the process. Have you checked the connection between the black and the yellow wires that run out from the thermostat and into the burner compartment? Can you see the actual pilot flame ( a small blue flame)? More often than not these days, there is not an actual pilot light, but a (sorry, can't think of the actual name for this part) glowing metal filament that ignites the gas burner. Can you see the filament turn bright hot red (maybe orange) when the heater is called on?

Turn on the hot water somewhere in the house and then feel the incoming and outgoing pipes at the water heater. Even if you can't hear the flow of water, you can feel the cold input getting colder as water travels through it and the output getting hotter as water flows out of the heater.

Is the water hot elsewhere than the shower? If you have temperature balancing faucets, it's possible that the balancing mechanism is stuck at the shower faucet. If so, you may have reduced hot water flow at the showerhead. Turn the faucet all the way to hot and see if you have about the same water pressure (flow) as the cold side.

The answer to these questions can give clues to the problem.
 

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