On-demand hot water recirculation

[ryoo1257]

After purusing the forums on a recirculation system I see that Grundfos is mentioned often, how warm is the water coming out of the cold water faucet?

Anyone have experience with this one, Chilipepper CP6000? Supposed to save energy because it is not running all the time and summoned by the press of a button. There doesn't seem to be too much info out there except a handful of negative reviews on Amazon.

I thought I read somewhere on the forum that using such a fast pump is bad on the copper pipes, for some reason.

[LiQuId]

grundfoss is mentioned often because their pumps are whisper quiet and Pure awesomeness.

I dont have experience with the mentioned product but if its getting negative reviews on amazon of all places then I wager its utter Crap.. using a fast pump is bad on copper becasue it prematurely wears on the piping and joints causing expensive problems in a short time ( replacing all piping )

What are you meaning by your question about warm water coming out of the cold faucet?? this often happens when a hot line is run too close and directlly under a cold, and also when a cold line is in a duct space for heating ..

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[LiQuId]

i just checked it out... its crazy loud. and as you have found has bad reviews. I would not recomend this product.

[ryoo1257]

Originally Posted by LiQuId

What are you meaning by your question about warm water coming out of the cold faucet?? this often happens when a hot line is run too close and directlly under a cold, and also when a cold line is in a duct space for heating ..

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good to know about Grundfos, will highly consider this one, and Laing Autocirc. I was reading on Amazon with regards to Grundfos, Watts(looks just like Grundfos), Laing autocirc, Metlund, and that Chilipepper, all confusing.

A couple of reviewers commented on how when they turn on the cold water faucet the water is not cold but a bit warmer. It's Amazon, I forget which system it was, though. One reviewer wrote this about the Watts which I found interesting...but whether it's true or not I would leave it up to you pro plumbers to discern. He wrote "I installed the Watts recirculating pump November '07, along with under sink mix valve kit in the kitchen. I bought an extra valve kit for the master bathroom sink. The pump timer was set for the busiest times of day. There was a nearly immediate improvement in hot water at both faucets, which was glorious! The cold water side runs warmer, but so what? But the story gets more interesting:

Being an engineer I was always a bit curious why the pump was necessary, since a law of thermodynamics states that heat always flows toward cold. Theoretically, the mix valves under the sinks ought to function without the pump. Well, one day I unplugged the timer to see what would happen. You know what? The faucets produced hot water just as fast without the pump running! Now we leave the pump off all the time. My advice is to save yourselves money and just purchase the undersink valve kits (about $50 each). The pump can always be added later if you find it's still necessary. Maybe some water systems require the pump. Hope this helps!"

So, no pump? just the undersink valve kit

[johnjh2o]

The watts and grundfos systems do work but any system that uses the cold water line to circulate the water will cause a slight cold water temperature rise. The only way to avoid this is to have a dedicated recirculating line.

John