OK, since you guys solved my last HWH problem (with the propane HWH in my attic), here’s another one for you.
I have two electric HWH’s connected in series in the basement (yes, it’s a large house). Within a single hour last week the following all happened:
1. The T&P valve opened on the first HWH, while my wife happened to be in the same room. She shut off the water valve to the HWH.
2. My wife called the water company to ask if there was any work going on in the water supply system in our area.
3. A Hot Water Heater repair truck showed up at my next-door neighbor’s house (we later found out he replaced his HWH, and the plumber recommended he install a pressure regulator).
4. My kids saw the water company flushing the fire hydrant across the street.
5. The water pressure began increasing/decreasing/increasing/decreasing/… for all of our house – shower, outside hose, etc. It’s been doing that constantly ever since! When watering the garden, for instance, it feels like a wave coming out of the hose every couple of seconds. The shower goes hot/cold/hot/cold/… at the same rate.
6. The water heater began clunking. It goes “click-CLUNK” about once every two seconds. It sounds almost like ball bearings in the pipes, but it is more of a regular sound. It stops sometimes, but is usually there. It’s been doing it ever since also. I haven’t been worried about that sound since one of the HWHs at the office where I work has been making a similar sound for three years now.
So the obvious questions:
1. What happened? I presume some sort of pressure spike in the mains.
2. Is there something that needs to be repaired/replaced/maintained in my HWH?
3. What is the clicking sound?
4. Is the waving water pressure related in any way to the clicking sound?
5. Could the water company have messed something up that they should know about?
6. What is causing the pressure waves?
7. What would cause a pressure spike in the mains?
The heaters are 40-gallon Rheem’s from about 1992.
Thanks,
Ken
Replies
For starters, teach your wife to shut off the fuel supply when the PT valve lets loose, not the water supply: usually, the PT valve will go when the unit has malfunctioned and the water is getting too hot and the system is being pressurized. (That might not be "usually" in areas with overall high pressure, but it is still a possible cause and shutting off the water without shutting off the fuel is potentially dangerous.)
Second, A Hot Water Heater repair truck? Do you have that sort of specialist? Or was it a plumber's truck?
3rd: I'd look to see if you have a pressure regulator; I'll bet it's been blown.
There are Water Heater Repair companies out there! I would even look into it if I was in a bigger area. These guys are usually very good... changing anode rods regularly, etc. Thought you'd like to know about this.
WHW I don't think that there are any companies that just do water heaters in my area (Kansas City).
But there are several companies that advertise how many service parts that they have on all of their
truck and that includes a new water heater. I am not sure what size or type that they keep on the
truck. Maybe a couple as they are often large size cargo van styles.
Often those have anywhere from 1 to 4 WH on a truck like that. In an old issue of P&M (a trade journal) I remember seeing a WH company that carried 6 plus they had a runner using a Chevy S10 pickup to bring anything that wasn't on the trucks. They had numerous trucks to do this. Interesting concept. If I remember right they were making good money doing it this way. They also did gas and vents for WHs.
Do you have a water pressure reducing valve installed? Darkworksite4: When the job is to small for everyone else, Its just about right for me"
This is pure speculation based on limited evidence and experience but IMHO it would explain most of the symptoms you describe.
If you water is slightly or previously hard I would suspect lime build up, possibly broken free when the hydrant check thumped your system, water hammer caused by the hydrants valve being closed rapidly leaving the oncoming water volume no place to go, is separating the water from the heating elements. Large pieces of lime can allow water to get to the element in small quantities that are so small that the element, sized to heat a larger volume of water, flashes it to steam.
The stream expands rapidly, shifts the deposit and pressurizes your water system. The pressure released the piece of lime falls back in place after allowing more water in to make more stream. The released steam cools rapidly and condenses back to its original size and returns the system pressure to normal.The sound you hear is the pinging and gurgling caused by this cyclic action. About every 2 seconds.
A damaged pressure regulation valve is the only other thing that I can think of that might have something to do with the pulsing pressure but I can't imagine how it would cause the noise described and would remain my second guess. Around here a limed waterheater is handled by replacing the unit.
Please let us know any new information or results. I love a good mystery and would like to find out how my hair-brained idea is fairing in the hard, cold world.
Speaking from recent experience, I would put my money on a blown pressure regulator. Hey, your lucky, I ended up with 120 psi of water pressure throughout the house and 2" of water on the floor in a matter of minutes. Seems somebody was working on the water main and somehow, not sure exactly, hooked the homes on my street to the high pressure side instead of the regulated side. Mine and several other homes suffered broken water lines and severe water damage. As a matter of fact, I just finished replacing the sub floor in the living room and have the dry wall cut back 4 feet up the walls.
Steve - in Northern California
More clues, based on today's exploratory research:
1. The clunking noise continues when the power is turned off.2. The noise continues when the power is off, and only cold water is in the tanks.3. The noise stops when the valve at the HWH's is turned off.4. The noise continues when only one of the HWH's is connected.5. The noise stops when both HWH's are disconnected, but the cold supply is connected directly to the hot side (how I love flex pipe...).6. There is no pressure regulator that I can find in my house.7. There is no expansion tank for the HWH's.8. The plumbing has always been rather noisy in this house (hammer, etc.). The house was built in 1992. It has four stories - basement, main, 2nd, attic - all with plumbing.
- Ken
Maybe you need a priest, not a plumber.
With electric heaters in particular, you need to make sure that
1) the hot and cold sides are hooked up properly because if they aren't, the water won't flow properly through the heater as it is heated (man, I wish I could draw you a picture!), and will cause hot spots where steam pockets can form, especially with a series system.
2) Check to make sure that the drop, or dip tube is in the inlet side. I've seen (so called) plumbers remove them because thay can't figure out what they are for. Or yours may be damaged.
I don't think the noise is steam pockets, since it is heard even when the power is off and the tanks are all cold.
The dip tube is a possibility, though, and that would even explain the hot/cold/hot/cold cycling.
The dip tube is a possibility, though, and that would even explain the hot/cold/hot/cold cycling.
How is this a possibility ?
Did you, or someone else remove the dip tube during that "single hour last week" ?
If you haven't been having this problem before, and are now, the only way the dip tube could be involved is if someone removed it, and thereby started the problem.
You're right - this all happened suddenly. It would only be explained by the dip tube falling off . And no dip tube problem can explain the inlet pressure fluctuations. The guage shows pressure fluctuations even with the HWHs disconnected.
So my best guess right now is a fluctuating high pressure from the city supply, plus some air bubbles in the line. Does anyone know if the city is required to meet certain standards for water delivery (pressure/volume, etc.)?
- Ken
You state might have some reg's on this, but probably not.
Also the "Americna Water Works Association" or for rual and smaller areas the "Rual Water Association" might have recommendations for these. Note, these are generic names, I am not sure what the exact names are for these groups.
But I suspect that it comes down to the cities design standards.
Call the city water department and get a hold of the engineering department.
I think that it is time to get a pressure gauge so that you can see what is going on.
I think that part of the problem might be fluctuation city pressure. But is it going from 40 to 50 psi or 80 to 150 psi?
Pressure Guage says...
75 to 85 psi on "click". 85 to 75 on "CLUNK".
Sometimes the pressure varies between 60 to 70, and sometimes between 80 to 90.
This seems a little high to me, but my highest fixture is 30 feet above the lowest.
Wow, complicated problem. Beats me. You need a plumber. Preferably one who does lots of service calls and trouble shooting. Avoid the new house guys and less experienced techs. You want an old timer who has seen it all and done most of it. Please let us know what the problem really was. I'm dying to know.
I bet there's air locked in the main supply somewhere. Probably needs blead out.
Just a thought.
From the what you have said, I would guess that the noise is coming from heat traps which are in your water heater to increase the energy efficiency. If your water pressure is rapidly varying, then water can be moving in and out of the heater and making the traps function...some heat traps make noise. I am not familar with how Rheem makes their heat traps but it is certainly the mostly likely source of your noise. Certianly the dip tube would not be expected to cause such a noise. If you are going to continue to experience such water pressure variations, I would strongly suggest that you install a water regulator and an expansion tank (on cold line before the first heater).
Fixed.
Adding an expansion tank alone did not solve the noise, but when the regulator was put in, the noise stopped. It still occurs when a neighboring faucet is turned off quickly, but only once, not repeatedly. I guess it is definitely a pressure-change related noise.
Thanks everyone for your help and ideas!
Ken.
Hey bill -
How do heat traps work (in general)? I saw a note on the HWH to be careful not to solder near the intake fitting, so I figured they were some sort of plastic baffle tubes. The noise would be more consistent with some sort of valve, however.
Some heat traps have a hard plastic ball which acts as a check valve so when the natural currents would tend to make the hot water rise out of the w/h, the ball blocks the flow. Others have a plastic flap. In any case, if you get them too hot, they will not function properly.
I forgot to say, it is well known that some of the ball type heat traps are noisy...they are used because they are more effective than most of the flap type heat traps.