hot water circulation pump makes noise, is this normal?

[John]

Hello group, Just built a new house and about to move in (doing punch list) and one of the things we had installed as an upgrade was a hot water circulation system to prevent water waste. During installation they did what looked like a really nice job, as all hot water lines are insulated in the slab (copper) They installed a "Taco" pump in the water heater closet, it is connected to the water heater where the drain valve is then goes off into the house. When the pump is plugged in you hear a distinct "hum" in the bedroom in which the wall of the water heater is shared. The pump seems to be hot soldered directly into this copper line and my guess is the pump vibrations are carried into the house this way. Is there any way to dampen this sound? Will the pump break in eventually and not make noise? Surely these pumps are designed to be silent, or I would guess they would. Hoping someone here has experience with this system. Thanks! John

[Charles Spitzer]

mine hums too. however, it's about 60' from the bedroom so it doesn't matter.

you'd have to put some sort of rubber connection between both sides of the pump and the copper pipes to prevent it from transmitting noise through the pipes. you'd still get some audible noise from the pump through the wall, if it's making any noise that you can hear when you stick your head in the utility closet. you'd have to enclose it somehow to get rid of that.

[John]

Hi Charles, That's what is wierd. In the water heater closet you don't hear it. If I touch the pump or the line I can feel it's vibrations, but if I go on the other side of the wall you can definately hear it hum. I wonder how I can put some sort of rubber or other flex line on the pump, it seems to be directly soldered to the copper lines..Being main line pressure my guess is it would have to be something durable and could withstand the heat. Will look around at plumbing sites and see what I can find. Thanks! John

[Charles Spitzer]

maybe it's rubbing on something in the wall, or using the wallboard as a sounding board.

[m Ransley]

If it was instaled wrong and run dry it would rattle. If you cant hear it in the closet the pipes are touching wood or walls, perhaps a piece of foam rubber where the pipe touches or is strapped tight will remove the harmonics. You are hearing a specific frequency that is resonating through a wall. Separation of pipe and structures and insulation should work. If it doesn`t work and it is just pipes a rubber collar is needed. Btw circulators need a shutoff, Timer and temp. Timer for after say 5. or your hot water pipes are heaters. you will waste more money in gas than you will ever save in water. A push button 4 min timer would be best.

Bottom line circulators waiste more energy heating water, than water costs. If distance is a problem gas tankless are best, even if distance is not a problem gas tankless can not be beat. Bosch or Takagi. My

1000$ unit has a 4-5 yr payback. A good investment.

[John]

"m Ransley" wrote in message news: [e-mail]...

Hi there! Yes, I think it might be the harmonics of the pump vibrating thru the pipe into that wall. May try putting a foam pad between it and the water heater and see if that might help. Also noticed the pipe coming out of it is heavily insulated and is wedged against the wall. Even though it's foam that might be the culprit too. They installed it with no timer or temp control. Was on the Taco website and saw they have nice timers and even a seven day digital timer that you can program differently depending on day. Also need to put the aquastat thermostat on it so it isn't constantly circulating hot water. I had the Takagi TK-1 tankless in my last house..Really nice unit..Two showers, no problem. The reason we went with the circulator on this house is the house is really long (one story) and has three baths. Also on septic and want to not waste water but will be very frugal with the pump so not to waste gas either. Just don't want the pump going on and off to wake up my guests as it is the guest bedroom which is behind the water heater. have concidered X10 automation with motion sensors in the bath and pushbuttons in laundry and kitchen. M. Ransley, you mention rubber collar on the water lines. This too makes sense, but do they make something for 3/4' copper lines? This is the sweated on pump so I am sure this would even complicate matters further. Thanks for all your help!!! John

[John Grabowski]

Since this is a new house and you haven't moved in yet, why don't you have the builder or the plumber address this problem. Add it to the punch list.

[m Ransley]

Best is cutting walls away from touching the pipe, You had a Takagi and now have no tankless , timer , clock, well wait to you get your bill and please report back. As there are alot of people that think energy savings do not exist. I have a Bosch so I know you do save alot me 50 % .

[Bob K 207]

put it on a timer so it shuts off at night & comes back on in the morning; it can double as an alarm clock :)

[John]

The Takagi was great. Really saved money, specially in the summer. Three people in a large house, nobody was shortchanged on hot water and could easily run two showers at once. I will have a timer and/or thermostat on the circulator before we start to use it. Have already identified one on the Taco website and is available at Grainger. The issue of the noise has been added to the punch list so will see what they do or say about it. Thanks everyone for the comments!!! John

[jay]

replying to m Ransley, jay wrote: There's no ROI for a $1,000+ tankless water heater. NONE. My gas bill is $6/mo in the non-heating months. Saving even half of that would take decades to pay for the difference. Tank is the best.

[JedW]

replying to John, JedW wrote: I had this problem after a remodel. Plumbers were flummoxed and after replacing the pump with a new one, they tried reconfiguring pipes and adding insulation. The noise just seemed worse. It was intolerable. Finally, we made them try an entirely different brand of pump (Taco) and the noise completely went away. These pumps should be silent, and good ones are!