Recirculating Pump gone bad?

[cap684]

We moved in to new house and found cold tap on all faucets have warm water (including toilets). I unplugged recirc pump and closed the valve and all water was cold so I plugged it back in. Would this indicate the pump is bad? There is a check valve present between pump and hot water heater. I should also note that the master bath tub hot water does not get as hot as all other faucets.

 

[Terry]

The Master tub may have a tempering valve on it to prevent scalding.

There could be mixing of hot and cold from the water heater location. You would need to follow the pipe to see if the proper checks are in place. Normally you just need to make sure that the hot return is going the correct direction. I like to install an aquastat that turns off the pump when the return reaches 108 degrees.

 

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[cap684]

I thought the same about the tempering valve, but the tub is dual lever. I took off the hot lever and did not find anything. I stopped at the cartridge, maybe I missed something?

I should mention that I am no plumber what-so-ever! Just been trying to research and figure this thing out.

The house is only 3 years old and the pump is a Taco 006. We had a plumber out last week and he had no idea but wanted to rip into the side of tub to see the plumbing inside...I requested we hold off on that for now.

 

[Reach4]

Feel or measure the temperature of the cold water line at various points. If the cold pipes are above room temperature, I would expect the highest temperature near the crossover/leak point.

I am not a pro.

 

[Earl]

We moved in to new house and found cold tap on all faucets have warm water (including toilets). I unplugged recirc pump and closed the valve and all water was cold so I plugged it back in. Would this indicate the pump is bad?

No the pump is not bad, this is normal for the most popular Laing brand. The reason is that when the unit senses the hot temperature supply drops below some threshold, it pumps this (now warm) water into the cold line until the temperature rises back up to the predetermined hot temperature. In other words it sets up a reverse loop through your hot water heater. Therefore, for the first few hours, even if only cold is turned on, it actually will be warm.
There are some devices out there which will pump the warm water back though a dedicated return line to the water heater. But that is expensive to install and typically only used in commercial applications.

 

[hj]

If his "cure" was to rip off the side of the tub, then he was either NOT a plumber or he was a fairly incompetent one. You "rip things off" AFTER you find out what the problem is and determine that that is necessary to fix it, which is seldom the case.

 

[Jadnashua]

There are more than a few ways to do recirculation, but if the house wasn't plumbed with a dedicated return line, it uses the cold water line(s), and as a result, it(they)will become at least warm for part of their length. Depending on the controls and the cross-over(s) will determine how warm they get. An inadvertent cross-over somewhere can make the cold lines warm, regardless of whether you have recirc or not.

 

[hj]

He said he "closed the valve" and it has a "check valve" so it is a dedicated return line, not a retro fit unit. But it still has several possibilities to cure it, even though cutting into the tub space is not one of them.