Bath Hot Water Flow Obstruction - Delta Model 602 Bath/Shower Valve

[Karl Weis]

My hot water side of the Delta Model #602 "Single Knob Handle Shower and Bath Valve" keeps getting obstructed over time with scale/rust, causing the hot water to slow considerably. I have in the past removed the ball assembly and hot water side seat and spring and been able to use a piece of wire to dislodge a small piece of scale that frees up the water flow for a few weeks, then it happens again. This did not produce any results this last try. Do I need to do some kind of a flush procedure to really clean out the hot water supply line here? I do not have the same problem at my other tub/shower on the other side of the wall. Do I need to do a "backflush" procedure back through my hot water heater while draining it to the outside? If so, should I backflush through the shower head, and would this clean out the debris at the hot water inlet side to the valve itself?

[Joseph Meehan]

How old is your water heater? If it is between about 15 and 7 years, it may be the problem. Many water put into service about then had a new dip tube design. The dip tube would fail and cause a number of problems.

I was one of the lucky ones. I found out about it and did a little research to find mine was one of them with the problem and repair was free. In order to get the free replacement you had to request it within the time the courts had set. I don't know if anyone could have a free replacement now.

As it turns out, mine was about ready to go, it showed damage, but was still in one piece.

You may want to check this out. I might add that different designed valves may have more or less of a problem with it.

One thing you can do to check it out is check all the strainers you have and see if any have small chunks of white plastic in them. The chunks are about the size of a grain of sand.

[Karl Weis]

[Joseph Meehan]

It sounds like you have a dip tube problem. While it would seem that 15 years is a little too old, I would not count it out. First it may have been the same problem, but not part of the agreement, or it may have been a similar problem and you will need to pay the repair cost.

Check out:

[Karl Weis]

[Joseph Meehan]

Sorry I don't know that valve.