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gdeangel
06-27-2014, 02:50 PM
Hello - I have an Amana / Maytag Model ASD2624HEB side-by-side refrigerator which started to make a knocking sound when using the water dispenser. It is about 9 years old.

It sounded like classic water hammer at the filter. The first time it happened, I removed the filter, dumped it out and then filled it with water at the tap, reinstalled, and the problem was gone. I think that was just dumb luck. The second time it happened, as I removed the filter, there was a "pop" sound of pressurized air being released. I proceeded to seat and unseat (tighten and loosen) the filter a few times until there was not more air-pop sound, then reinstalled the filter and everything was fine for another few days. Now the problem is back. This time the problem persists even after air-bleeding as above. I tried with the bypass cap in place of the filter, and the knocking is still there. It happened after dumping out the whole ice bin, but as it was making the new ice there was no water hammer. It only seems to happen when dispensing water. Also with the filter / bypass cap OFF, if I push on either nub-valve (there are two cross shaped nubs arranged vertically) to manually activate them, the water comes squirting out in bursts and the knocking sound happens just like it does when you activate the water flow from the door dispenser.

I got here following a thread on another forum that described similar symptoms, but apparently the appliance forum there shut down. That one suggests it could be (a) incorrect filter, (b) filter head, (c) lines, (d) shut off valve, and (e) fill valves. I did change the filter a few months ago, but the filter was purchased in a lot with others that have all worked fine. The case on that other forum was the filter head, but in that case the knocking went away when the bypass cap was installed. I searched repair clinic and there seems to be only one inlet valve for both water and ice - and also since the problem happens even when manually actuating the filter head, I'm inclined to rule out the valve electronics. I have no reason to suspect the shut off valve which is hasn't been touched in 8+ years. That leaves me without a clear idea of what I should start with.

Pulling it out of the cabinet space to get at the guts is going be a real pain... putting it off until I know where to begin. Thanks in advance for advice!

jeff1
06-27-2014, 05:24 PM
Hi,

If not air in the lines ( which often happens after a repair or filter change ) the fill valve, house water pressure ( esp if a little low ) or water tank/reservoir as prime suspects. If the fill valve cannot shut closed it can flucuate causing the noise ( lower water pressure also can cause the fill valve to not close properly ). I'd be inclined to bypass ( join the 2 lines together ) on the water tank/resevoir to see what happens. If still the same, fill valve would be a good place to start.

762 LINK> Dual water inlet valve (http://www.repairclinic.com/referral.asp?R=153&N=1071263)

763 LINK> Plastic connector for 5/16 inch plastic water line (http://www.repairclinic.com/referral.asp?R=153&N=298777)

jeff.

gdeangel
06-27-2014, 08:38 PM
Hi,

If not air in the lines ( which often happens after a repair or filter change ) the fill valve, house water pressure ( esp if a little low ) or water tank/reservoir as prime suspects. ...

jeff.

Here's a quick update: Since the easiest thing to get at was the shutoff valve I gave it a look and it was partially closed. That would reduce pressure, so I opened it up all the way, and the knocking stopped. However I think that is only a band-aid fix because (1) nothing has changed in the overall house pressure and it was working for 8+ years with the valve partially open and (2) as I run the water from the dispenser continuously with the refrigerator side door open, I can hear a very faint sound of air bubbles flowing through the filter / filter head.

So air is somehow getting into the lines, probably accumulating during "idle" periods which creates an air pocket. I think it was too much air to purge with the partial pressure from a restricted shutoff valve. With the shutoff wide open, the higher pressure seems to have purged the air pocket. That's just my theory. I understand the issue with the intake valve opening and shutting improperly would cause a knocking sound, and could even cause hammer from the pressure of the water flow, but it wouldn't involve air in the line, correct? What would be the issue with the reservoir that would cause the hammer, and is it related to air in the line?

jeff1
06-27-2014, 10:04 PM
so I opened it up all the way, and the knocking stopped. However I think that is only a band-aid fix because (1) nothing has changed in the overall house pressure and it was working for 8+ years with the valve partially open

Will only change the pressure to the refrigerator. Things like the shut off valve will get a build up inside over time causing low(er) pressure.

Water hammer isn't just air....we get it on washers when the fill valve closes too fast and the water has no place to go when the valve shuts off the flow and the pipes bang.


So air is somehow getting into the lines, probably accumulating during "idle" periods which creates an air pocket

Not normally but is possible...if there is a place where air would get in, we normally would see a water leaking out.
Chilled water tank/reservoir is one place where air can gather.

jeff.