reduced hot water supply

Plumbing Forums

Help Support Plumbing Forums:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

SGkent

Thank You
Joined
Jul 19, 2016
Messages
119
Reaction score
11
Location
near Sacramento, CA
One last question for a newbie. I have put this a separate thread in case anyone searches for the same issue.

Our hot water is reasonable throughout the house except at the clothes washer which it is always much slower than the cold. I have replaced the washer valve and swapped hoses to see if it is one side or the other, and the problem always follows the hot water faucet on the wall. I have replaced both laundry faucets and that did not change anything. The supply lines to both are 1/2". The main cold water is 3/4 to the reducer where it drops to 1/2" thru the house. The hot water comes off the 3/4" cold line and is 3/4" to the water tank and a 3/4" outlet where it goes back up inside the wall to a 1/2" reducer adjacent to the cold water reducer in the attic. The 1/2" hot and cold lines parallel each other thruout the house. The only difference I can see is that the hot water has about a 10' longer run of 3/4" than the cold water because of the drop to the water heater in the garage and back up to the lines in the attic. Both hot and cold drops to the washer come back down from the attic as 1/2" pipe to the faucets I replaced. All pipe in the house is copper.

About 2003 I replaced the water heater with a AO Smith 40 gallon unit. The nipples at that time were new, and the problem still existed when the water heater was replaced. I did find a penny inside the old water heater and I have no idea where that came from but I think it was too big to fit inside the pipes so maybe the original installer tossed it in there as sacrificial - I don't know. There is a gate valve on the cold water side just above the water heater. It is fully open, has a red handle, probably put there in 1979 when the house was built. I used this style lines when hooking up the water heater. They have 3/4 fittings and are about 16" long. Can these be the cause of the historical slower water supply on the hot side?

026613142838lg.jpg
 
Last edited:
Thinking the same thing, I put in a new valve, then the hoses at the faucets a while back to see if the problem followed the valve, hoses, or the faucets. It followed the faucets meaning the hot side hose connected to the cold faucet increased in flow strength, while the cold side hose now attached to the hot faucet on the wall slowed. The problem reversed sides making it unlikely the issue is in the hoses, valve, or washer.

I did not know if water heaters in general slow the flow by design, or the flex hoses I used could be responsible.
 
I suspect this is going to end up one of those duh moments.

One of the guys I work with here has a side business as a handyman, of which he does a lot of plumbing. I thought since I am asking why not run it by him. He said he has run into this many times before. Some manufacturers have a rubber protector which looks like a gasket deep inside where the nipples screw in that has slits in it. He said most likely I left those in and they are restricting the flow. He said if I remove the nipples they will probably still be there. Said he sees it all the time when that specific complaint comes to him.
 
well that did not work well. Called a local plumbing supply who sells AO Smith to buy a new dip tube and anode. The water heater was installed in late 2003. So they had trouble figuring out what anode it took. They also could not locate a dip tube for it. The model is FGR-40-248E, S/N GE03-1551769-248E. Part number FGR-40-F00L010S45 I guess there is some homework to do. I noticed that there is a sticker pasted over where the anode would be, and it says relief valve. The spot on the side for the relief valve is plugged, probably at the factory. This is how it came. My research leads me to believe that this could be a unit with a combo nipple and anode on the hot side, and the dip on the cold side. The pressure relief looks like it is all brass so I doubt if there is an anode under it. I am also hesitant to pull the top off to see if there is an anode hidden inside the top inside the foam.

Anyone know from the photos exactly what I am dealing with. The last WH lasted 24 years. This one is at 13 years and I thought maybe by swapping out the anode and dip tube I could get close to what the original got with some luck.

Serial
aosmith-kent.jpg


Relief
aosmithrelief.jpg


Top
aosmithtop.jpg
 
Last edited:
yes but I found my problem and created a real mess.

The anode is a combo anode. It is some metal and mostly gel. some of the pieces fell off obviously and while I figured they would flush out thru flushing the tank into the driveway, some carried into the house and stopped up every hot water faucet in the house. I ended up having to use compressed air backwards with the hot supply line into a bucket until each seemed Ok and several took many tries to get opened back up. As soon as everything is flowing and tidied up the drain fitting starts leaking (no heat is on yet) and when I touch it the leak gets worse. So now the water is back off and I am draining the tank again so I can remove that valve and see why it is leaking so bad. The reason that the hot water is slow to begin with is because that is the design.

This tank has an optional factory installed pressure relief in the top where a plug anode normally is, that is what AO Smith called it in the early 2000's documents I found online at archive.org. The anode has a 2" riser, a 2" body and guess what, at the bottom of the riser are two small slots that the hot water exits thru. Not sure what I am going to do. One option is to move the pressure relief to the side if the plug will come out, and put a standard nipple in the tank combined with a plug anode like they usually have. It is 11:00 pm and we get up at 5 so maybe I am not going to work tomorrow. We'll see how long it takes the tank to drain and why the valve is not sealing.

this is the restriction and the style anode that is in it. You can see the hot water exit holes on the side. Rather limiting.

drain valve was leaking because the rubber washer split. Replaced it and we have water in the house again. Now to find the parts to keep it energy efficient.

ComboRod90.jpg
 
Last edited:
Read the section on ALUM anode rods (and the miseries they can cause) at the same place you sourced the combo rod photo.

When you get the plastic drain valve out, replace it with a 3/4" full flow ball valve for easier future serving.

Sediment Draining _4  Drain - Full Port Ball Valve.jpg

Heat Trap Nipples - Bradford White.jpg

WM Inlet Filter.JPG

Filtration @ Outlet High Temperature Water Filter Housings - WH34 & ST-1.jpg

GRD-Bonding _2.jpg
 
Read the section on ALUM anode rods (and the miseries they can cause) at the same place you sourced the combo rod photo.

When you get the plastic drain valve out, replace it with a 3/4" full flow ball valve for easier future serving.


Actually you can use a monkey wrench LH if you use a RH one while standing on your head. :)

I read the page, quite informative. The filters you posted would have been nice last night. The rubber washer on the valve split into two pieces and that is why it was leaking. I replaced it with a spare and it sealed up but I like the idea of the ball valve.

Called AO Smith to see if they could locate the model, what a joke. Sorry we don't keep any "data on models over 10 years old."
 
aosmith-kent.jpg


:eek:

Here is your Parts List- (Will Be Back)

I was instructed repeatably to find a dedicated LH monkey wrench on a certain contributors service truck. It took me a few attempts to realize that there is no LH wrench.

These exercises in futility usually occurred on FRI afternoons after lunch... :mad:

FINAL EDIT- :rolleyes:

OK, it seems there is no info (not archived) regarding this model (FGR 40 248E) @ http://www.hotwater.com/resources/pr...e/parts-lists/

While carousing with my browser, I came across this-

These are very good heater but they are no longer available in most counties of California due to LoNox AQMD requirements.

Think about exchanging the aluminum anode for a magnesium.
 
Last edited:
Think about exchanging the aluminum anode for a magnesium.

one would think that in a city the size of Sacramento and area - 1.5 - 2 million people the few plumbing houses here would have various models to choose from rather than "we can order one." or "I had one on the shelf for 4 - 5 years before it sold. Why not buy a new water heater."

I believe this will be resolved but I haven't a clue when. Part of me wants to move the pressure relief from the top to the side, install a nice drain, and swap in a standard magnesium plug anode. The other part wants to keep the energy efficiency of the combo style anode. The dark side of me sees the plug not coming loose on the side where the pressure relief would go in this swap... . after all, I was able to break a one inch Craftsman breaker bar on an axle nut on the VW bus once, I certainly can break a smaller one to get the side plug out, or worse, only 1/2 out and leaking ... .
 
Last edited:
impact wrench.
Magnesium is further down the chart on the galvanic series, so it probably offers better corrosion protection. There are some issues if you have well water with sulphur content, the magnesium can produe sulfure oxide, or dioxide, and put an odor in the water. In those instances, you go with the aluminum.
 
Most depends on water quality and how the WH was installed. The ALUM rod will give you exactly the problems you have now. The rod breaks down more quickly and gives off the particulates (and bacteria) you have experienced.

If it were mine, I would flush the hell out of it and install a combo rod of the suited material. Then flush on a needed schedule.

That same site where you came across the anode photo has an extensive page dedicated to anodes and they can also supply about any one you may need. The choices of anode rods are ALUM, ALUM/ZINC, MAG and powered. You have to decide which to use with your particular water source.

Combo Rod - Damaged Water Feed @ Nipple.jpg
 
If you are patient enough to read through most WH manufacturers part lists, they will offer anodes of differing materials.

I would imagine the biggest reason that supply houses don't stock them is low demand. Most usually replace the appliance instead of servicing it.

Online supply houses are a better source I think. It seems every time I went into FERGUSONS they didn't have what I needed and would have to order usually with a hefty handing fee.
 
AO Smith sent an e-mail that they could not locate any parts list on the model. My guess is that because it was for Sacramento Air Quality rules they did not make that many of that series. They recommended 3 different standard anodes. I found a couple anodes that were combo but no one in town had one so I gave up on hoping to find it locally. I need to add the expansion tank and plan to do it this weekend. Ferguson had a standard 45" KA90 rod that I went with because the mag one they had was short. We pass their supply house on the way home so it was easiest to get it there. The other supply house who had rods was about 1/2 hour out of our way. Buying on the Internet everything was a week from delivery unless a huge shipping price was paid. Hopefully the pressure relief plug will come out and I can move it. As I indicated our water is mostly Sierra snow runoff from the American River, and has very few minerals in it. The last WH lasted 24 years. By using a standard anode I am hoping to get another 10 years from this one. Fergusons said right now they are supplying electronic control units for the newest water heaters almost once a year on many. They said it doesn't matter which manufacturer but almost everyone is seeing a 100% failure rate on the control units in warranty. The blogs and ratings services online have the same pattern of comments so I'd like to keep this one with a mechanical burner control going for as long as I can until a time when the WH manufacturers are more reliable again. Thank all of you for your help and suggestions. I appreciate it.
 
Last edited:
Back
Top