Any favorite or least favorite manufacterers of these? I know they are notorious for cheap construction. I’ve got two kitchens with long runs to the domestic WH and need to provide faster hot water with a small 120V WH. 120V is already roughed in.
Scott.
Learn how the pros keep their hand tools sharp without breaking the bank.
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.
Start Free Trial NowGet instant access to the latest developments in green building, research, and reports from the field.
Start Free Trial Now
Replies
Another option is to install a HW recirculation system.
Bill has a very good point recirc lines are the method of choice I have installed more than I can remember & the small pumps being under a hundred bucks & cost less than a light bulb to run work great. Here is the kicker if you can't install another line from your sink to your water heater than a point of use pump works great it forces the hot water back into the cold side untill it reaches the desired temp.
This sounds like a controversial issue, "costs less than a lightbulb to run", I'd like to see the math behind the cost of keeping all that hot water moving continuously through 100 feet of pipe, losing heat all the while. And then there's the (small) cost of running the pump. I'd like to see cost comparisons with this versus keeping 1 gallon of water hot under the counter.
Anyway, this house is already built, so adding a recirc line would be costly. Unless there is a clearly better alternative I suspect it's best to use a small under sink unit.
Thoughts?
Scott.
OK I was referring to the pump energy usage the small pumps are 1/17hp so the current is minimal. As far as heat loss you have a good point every hot water line should be insulated. Like I said if there is no way to install a new pipe point of use pumps which install under the sink have several modes of operation some work on timer others on motion detectors they kick on when your about to use them forcing hot water into the cold pipe until it reaches the desired temp. I recommend this over another water heater for a couple of reasons 1 most point of use water heaters have a relief valve that needs to be indirectly ran to a drain or daylighted outside of the house check your local codes. 2 rather bulky take up too much space in my opinion, and 3 water sits in these stiles too much causing corrosion. but if your sold on using a water heater under your sink Bradford white makes excellent residential small water heaters as well as A O smith. I don't recommend point of use tankless unless you have 220 available cause the 110 systems restrict the flow so much to get a good temp rise it makes your sink run like a coffee pot. and one last thing here is a link to an undersink pump. hope this helps http://www.grundfos.com/web/HomeUs.nsf/Webopslag/PAVA-56TMVA
"I'd like to see the math behind the cost of keeping all that hot water moving continuously through 100 feet of pipe, losing heat all the while.I'd like to see the math behind the cost of keeping all that hot water moving continuously through 100 feet of pipe, losing heat all the while."But they don't.Via either a timer and/or thermostatic control they only run a fraction of the time.
Thanks guys. Good points. I've got some reading to do.
Scott.