Residential Hot Water Recirculation issues

[RyGuy]

Howdy Folks-

I am a homeowner, well my dear sweet old widowed mother is the home owner, I just live here and help keep things around here in decent shape.

When we moved into this house in 2005 (built in 2003) we had installed a water softener and about 8 years later a Grundfos hot water recirculator, with those little bypass or free flow hoses underneath 3 of the sinks in order to get hot water to those areas quicker. At the time we had them replace the hot water heater at the same time they installed the water recirculation device, due to several issues with the original heater. We got a good deal, or so we thought. While we now had hot water on demand thanks to the pump, I noticed that when turning on the cold water, we were getting hot/warm water from there, which seemed a bit awkward. Foolishly I let it go a few years until the water softener crapped out 2 years back, and we had a highly reputable company come in and replace that. He pointed out at that time that he did not think things were plumbed in correctly with the original water softener as well as the recirculation pump, and offered to have one of his contractors come take a look. Well as it turns out, the plumbing was indeed not done correctly. Resign from the water softener had gotten into the hot water tank and filled the bottom part of the tank. he could not drain it out because the resign was like mud in there and also blocked up the flush/drain ports on there. He tried for about an hour or so. It was then decided to go ahead and replace the hot water heater since it was pretty much toast with that resign sludge in the bottom of it that wasn't going to go anywhere. He said he would get things plumbed correctly. We also have him install a whole house water filter system as well. And so we thought he did. We are very pleased with the water softener, however- I get hot water coming out the cold water side everywhere in the house as long as the pump is on.

I've gone over this in my mind over the past year or so and I've come to the conclusion that perhaps there needs to be a check valve of some sort to prevent hot water from contaminating the cold water side with having this recirculation pump? There should be no reason why I have to run my cold water for a minute or two in order to get cold water! Also- because of what is going on, is it a good bet that resign from the new softener has gotten back into the new hot water heater and contaminated that one?

Thoughts?

Thanks

Ryan

 

[KULTULZ]

-Snipped For Brevity-

...and about 8 years later a Grundfos hot water recirculator, with those little bypass or free flow hoses underneath 3 of the sinks in order to get hot water to those areas quicker.

... I noticed that when turning on the cold water, we were getting hot/warm water from there, which seemed a bit awkward.

Click Here and Read This- -Passive Flow Control causes a number of Hot Water Circulator problems on systems which utilize the cold water line as the return line-

The below illustrations depict how check valves, thermostatic valves / sensor valves and thermostatic elements are designed to easily allow flow in one direction (hot line to cold line) while preventing flow in the opposite direction (cold line to hot line).

Thermostatic valves remain OPEN anytime water contacting them is less than 95F, and

...water easily siphons out of hot water line when valve is in default OPEN position

Additionally when these valves leak, you are introducing contaminated water heater waater into your drinking/bathing water.

 

[Mr_David]

Replace the thermo valves under the sink. one has failed and allowing the hot water to continue flowing into cold system.