My contractor says either I get two tankless water heaters (mid sized or small size) nor have a high capacity one with recirculation pump. The reason is, I have 3.5 baths, I need tankless heater to be installed in my garage(in a corner so the water heater will be at the left most of the house) which is next to kitchen and laundry(laundry is in the garage right next to the water heater), and a bath is right above the garage which is fine. 1.5 baths in first floor are in the middle of the home, the master bath is at the farther end of the home ie it is diagonally opposite side of the garage. Which is the better way to go? Also, one of my friends uses noritz-084m and his house has 4.5 bath, kitchen and separate laundry room. I dont see any recirculation pump on the noritz nor does he has another water heater. I am perplexed now.

i would be inclined to use a small heater for the master bath and a medium for the rest. no recirc..
why don't you contact noritz and speak to one of their specialists.
one thing you must be aware of..
you will be sizing the gas line for maximum continual usage which could be over 400,000 BTU when you include 2 heaters, cooktop, dryer and oven..
your gas line and meter must be sized accordingly.
noritz site says the heaters are recirc compatible but they 'recommend' a 8 to 10 gallon storage tank.

if you don't care about instant hot water then don't get a recirc pump.....if its something you want then get it

its never necessary

I also agree if your going to get 2 tankless units that id put 1 small under the master bath and have the 2nd one for the rest of the house...

im not a fan of tankless....I think they are a scam...id just get a 50 or 75 gallon tank unit and save $4,000

i'm with ya on that one. wauke..

Thanks. In that case, do you think the second water heater is necessary? Can I just get the 50 gal or 80 gal for the entire house and get it installed in the garage? Thanks.

yup, with a much simpler recirculating line than noritz shows on their site.
you can have the recirc line set up with a motion sensor in the master bath. it will not run until someone is actually in the bath. so if you go into the master bath to take a shower, by the time you get your towel, shampoo and soap all ready, the pump will have been called on and hot water will be at the faucet.

packy,
you mean to say, get a 75 gal tank with recirculation pump? I heard, I will be burning more energy with recirc pump usage. Is that correct?

In any case if yes for recirc pump, what is the recommendation for both? I want the pump to cutoff when recirc water reaches a certain temperature. Appreciate it.



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there are many ways to wire a recirc pump. you can use a timer so it comes on only certain times of the day or night. that is the most common way. of course you would have an aquastat at the return end which would turn off the pump when it senses warm water. and of course all the hot water pipes and the return pipe would be insulated.as i said, a motion sensor can be incorporated into the wiring so the pump knows to come on when the master bath is being used.
bradford white makes very good water heaters. a quick recovery model with a higher power burner is required if you are going to have a car wash type shower with multiple body sprays and shower heads.
a Grundfos recirculation pump, model UP 10-16 BN5/ATLC which has a built-in aquastat, timer, check valve is the type pump i would use.

Thanks Packy. From energy perspective is recirc a good option or will I be burning same or less or more energy as a second heater?

Appreciate the reply.

Comparable when it's running to a 30 or 40 watt lightbulb.Probably less, because that would be a boiler circ. Minimal power usage anyway.



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Thanks Paul. Then I will go with a 50 gal with recirc pump

the key to efficiency is to INSULATE BOTH the HW supply pipe AND the recirc. line

the recirc. line can be 3/8" OD and insulated with 'rubbertex' slip on

the supply line (preferably) would be insulated with 'split fiberglass'

the insulation will save you $$$$ regardless of any recirc, line

an 'aquastat' on the return circ. line near the water heater to control the SMALL pump is a good thing

some pumps have the 'stat' built in and plug directly into AC power - available from our sponser


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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638



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As Bernabeu said .... insulate insulate insulate.

With a recirc pump you've created a radiator .... the pipes are going to give off its heat and that can cost you a LOT in energy loss.

Again.... any moneys you put into "over" insulating you will get back in a short time and if you fail to insulate at all its just a matter of time when if you're like many people most likely will turn off your recirc system completely due to the heavy energy expense.