The Tank › Brand new A.O. Smith GAS WH with sediment, low pressure, need help!
- December 3, 2017 at 1:13 pm #23976
First let me say thank you to the creators and contributors of this site, it is truly helpful and I have learned a great deal from reading through the articles and forums….BUT I am not sure what to do in my situation and would appreciate some advice before I buy any parts or possibly a new WH. Please beware, this is a LONG post, so I apologize in advance and thank you if you take the time to read it…I am just trying to paint a complete picture so you can know everything I know.
Here is the background. I am living in my new house in Los Angeles. The house was built in 1948, but I have remodeled from pretty much the bare studs, in addition to adding about 300 sq. ft. to the main structure. I say this so you know the plumbing is all brand new copper. During construction, my contractor had issues with the first plumber who was doing the rough plumbing work and was fired. Before he was fired he had installed a brand new line from the street (1.5 inch copper line) along with a pressure regulator and relief valve. Part of the new main line runs underneath a 3 foot wide sidewalk. This is relevant for a few reasons. One, I know he pushed the pipe under the sidewalk to connect to the meter, but I dont know if he capped the line when he pushed it under so I am not sure if dirt or anything else got in it. Two, I actually dont know if the whole line is copper. I can see where it comes out and goes through the house foundation is copper but without digging out the front yard, I can’t be 100 percent sure part of its not galvanized.
The 2nd plumber who came in finished the rough plumbing and it seems like he did a good job. I have a return line for the hot water and a separate cold line for the fridge, pot filler, and whole home humidifier that runs through a sediment filter. The 2nd plumber DID NOT install any of the fixtures, WH, or filter. My contractor was only hired to do the rough work, so once the drywall was up and the rough plumbing and electrical was done and permitted, he was gone.
A 3rd plumber was brought in for the finshing work and WH. I purchased a 50 gallon A.O. Smith gas WH and a Grundfos UP15-29su recirc line pump, which was installed. However, please note that between the rough plumbing being finished and the final plumbing work being installed, about 3 months passed. My 3rd plumber complained that the 2nd plumber did not flush the lines before he capped them and that there was some issues with the lines. Ultimately, he says he flushed them but we had a few sinks that had low pressure from day one of when we moved in. I chalk this up mostly to gunk being in the screens and cartridges that the 3rd plumber never flushed out because after about a week of my wife complaining, I managed to flush them out and get them working at proper pressure. Since then, however, I have been in a recurring cycle of sediment and gunk build up and low or almost no pressure in some of the faucets and showers.
The worst problems have been the kitchen sink and master bathroom, I have flushed these lines about 5 times now (these are the heaviest used areas). For the master bathroom, I have disassembled the main thermostatic valve 5 times, cleaned out the gunk, cleaned out the cartridge, and reinstalled. After each cleaning, pressure and normal temperature control resumes, but only temporarily. I also have issues with maintaining hot water temperature in the shower, it will last for about 5 minutes then I need to increase the temp, at which point pressure also decreases.
I have also flushed the water heater once at this point. I drained it with a hose completely, then turned the cold supply line on for 15 minutes to flush it. During the flush, white and green sediment came out in somewhat alarming amounts. Towards the end of the flush, the amount decreased significantly, but if I held my hand under the hose, I could still feel some granules of sediment coming out, but they were mostly clear, not green or white. After this WH flush, I flushed all the sinks and showers and for 2 weeks I was good, but then the low pressure and temp loss came back. I should also note the grundfos recirc line pump is ALWAYS on, as in, it’s not connected to a thermostatic switch or timer, it was just ON 24 hours a day..I did fix this issue yesterday myself, and installed a timer switch based on reading some of the comments here about the recirc line being a culprit of sediment in screens and cartridges some times. If you are wondering why it was always on, i have no idea…my 3rd plumber who installed it said its not a big deal but somehow that does not reassure me.
So, at this point I have brought in a 4th plumber who has told me I should buy a new WH since the tank on my current one likely still has sediment in it. I am not eager to do this and am willing to try and use the flush kit sold here and see what happens. I have also asked my neighbors if they have hard water or pressure issues and none do. So, I am not sure where the sediment is coming from…whether its from the new line being shoved under the sidewalk, dust and debris entering the lines during construction, or just left over residue from connecting so many new copper joints. I also called A.O. Smith yesterday and got some conflicting information. One rep told me my model WH has a magnesium anode rod while another rep told me it was aluminum. Both confirmed the anode rod is in the cold water supply inlet and there is only 1 rod. I have not removed the anode rod to see if it is corroded…i just cant imagine 3 months of living here would corrode it.
So, that is it. I know this was super long and detailed and I thank you for reading this, I just wanted to be thorough so you get a complete picture of the situation. Any advice or ideas would be greatly appreciated. Should I try the flush kit? Should I get a pre-filter for the WH?December 3, 2017 at 4:03 pm #23977geno03245Participant
I would start investigation by digging hole(s) in front yard … this will indicate possible source of problems.
Then locate outside spigot that is closest to incoming water line. Open this tap full flow and note color of water. Use a paint strainer catch what comes out.
When experiencing low pressure inside house, put a water pressure gauge on this spigot…. this will give you a baseline of incoming water pressure.
Don’t replace the tank …. buy a cheapo plastic tank rinser that connects to garden hose, and insert into drain valve…. hopefully you have full flow valve, or a brass drain valve that can be removed… the thicker insulation around tank might make drain removal difficult.
If outdoor line is suspect, put a water filter on the line to catch stuff before it enters house… then stock up on filters, and consider re-plumbing the street line.December 3, 2017 at 4:41 pm #23978
Thanks for the reply.
Are you suggesting the holes in the front yard to check for leaks or to check if it’s galvanized and not copper?
Will do the other suggestions and report back.December 3, 2017 at 8:49 pm #23979Larry WeingartenParticipant
Hello, I’ve a few comments also. There is no way you need a new tank. Did any of the plumbers install a check valve in the return line from the recirc system? If not, you are likely getting sediment from the heater into the lines. A photo of where the line connects back to the heater would be nice to see. Your heater likely has an aluminum anode rod. Replace it with a magnesium rod to greatly cut sediment generation. Check for cross connection in the plumbing. That test is described elsewhere on this site, but could be part of the problem of insufficient hot water at times. And lastly, I would not expect a modern day plumber to use galvanized pipe as it’s much more work. I would expect to see PEX, (which I like) or copper. 😎
Yours, LarryDecember 3, 2017 at 11:46 pm #23981
Thanks very much for the reply, Larry!
I’ll do the crossover test tomorrow and report back. I’ll also send over a picture of the recirc pump setup, but I’m pretty sure there is no check valve installed, but I could be wrong.
I checked the main line in the front in 3 places, definitely all copper and looked like it was in good condition.December 4, 2017 at 12:14 pm #23984
Here is a pic of the recirc pump.
I also checked the color of the water at the spigot closest to the main line and its clear, no visible particles or sediment so I dont think its from the city line.
Also, i tried something last night. I turned off the recirc pump completely and left it off overnight and this morning. My temp issues in the master shower seemed to be gone…the hot water maintained temp the entire time. Pressure still seemed slightly low, but it was at least consistent.
Larry, I also tested for cross connection and couldn’t find any faucets that ran while the WH supply was turned off…still think it could be a cross connection issue or is it a bad check valve on the recirc pump?December 4, 2017 at 12:36 pm #23985Randy SchuylerKeymaster
Please give us another picture of the line just upstream of the recirc pump. That is where a check valve would probably be if there is one.
Randy SchuylerDecember 4, 2017 at 12:51 pm #23986
Thanks for your response. Here is the pic you asked for.
Also, I removed the pump and flushed the recirc line and the water is green, in addition there are bits of copper pipe shavings and particles. I’ve flushed it all out it seems, but there is still a bit of stuff floating on top of the water still. What do you think?December 4, 2017 at 1:04 pm #23987Larry WeingartenParticipant
Hello, I don’t see a check valve. The way I like to set up a recirc line is shown in the drawing. I prefer to use a spring check valve as they hold up better and make a more positive seal than a swing check. Another photo from further away would give us a clearer idea of just what you have, but certainly a check valve is a must. In the meantime you could just turn off the pump and close a valve in the line to see what effect that has on hot water delivery. 😉
Yours, LarryDecember 4, 2017 at 3:25 pm #23988geno03245Participant
Check the manual … but I’m pretty sure that series grundfos pump is installed vertically …
..while a swing check valve is installed horizontally…
… a spring check valve might be specified for vertical, the installation sheet would say.
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