Recirculating water heater/pump?

Supermatch

Supermatch

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My wife is looking at alternatives to a piece of equipment for her business, as none are manufactured domestically, and freight shipping from China is over $1000 before duty and costs of getting it to/from a terminal.

The idea requires the use of a plastic basin that recirculates hot water to a regulated temperature. Ideally, we're needing an all-in-one 110/120v plug in device that is quiet (ideally no louder than an aquarium pump) that can heat and pump about 1.5 GPM while maintaining an outlet temperature of 100°F. It can either maintain temperature of the water basin which will have water circulating like a fountain, or right at the outlet. Volume of the basin will likely be between 10 and 20 gallons. If we need to split this into two separate components (pump and heater), that is also an option if we keep current draw low enough (standard outlet, so figure < 15 amps).

Any thoughts on this? I'm not sure if there are aquarium pumps/filters that can maintain that temperature for that volume/flow of water (the few I've seen that looked suitable maxed out at 90F), or if there are maybe something intended for RV's or similar that could work. Ideally we would not require a heating element in the basin itself. Suggestions would be greatly appreciated.
 
Maybe something designed for a hot tub, or maybe even a church baptismal pool (though that may be overkill)?
 
Supermatch said:
It will get dumped after 60-90 minute of use.

My issue with the RV heaters is that I don't think there's any way of recirculating the water back into them.
Click to expand...

If there is an inlet and an outlet, you make a closed loop system, Heater -> basin -> pump -> heater. Your pump recirculates water back to the cold water side of the heater.
 
Supermatch said:
It will get dumped after 60-90 minute of use.

My issue with the RV heaters is that I don't think there's any way of recirculating the water back into them.
Click to expand...

The one I linked has a cold input and hot output so it should do what you want as long as you put things in the right order.

Here's my engineering schematic:

1697561438101.png

Edit: nvm you'll need a tankless heater like this
 
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Yep - if I go that route, I'll just need to find a pump that can handle being deadheaded or has an internal bypass, since I will likely have to regulate the outlet pressure to the nozzle where it returns to the tank (need more of a trickle than a jet).

(I've also been deceived by the blue "inlets" a few times on the heater photos).
 
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I would separate the pump from the heater.

Grundfoss makes quiet, commercial duty pumps for in-floor radiant heating systems. They last for years. Depending upon how huch heat rise you need a 120v engine block heater for a diesel engine can provide the heating source. They usually utilize a 3/4" ID hose.

Amazon product ASIN B000JGH2F6

Amazon product ASIN B097J5NVGP
 
Scsmith42 said:
I would separate the pump from the heater.

Grundfoss makes quiet, commercial duty pumps for in-floor radiant heating systems. They last for years. Depending upon how huch heat rise you need a 120v engine block heater for a diesel engine can provide the heating source. They usually utilize a 3/4" ID hose.

Amazon product ASIN B000JGH2F6

Amazon product ASIN B097J5NVGP
Click to expand...
Heat rise needs are minimal. Water will never start below indoor ambient temps (70ish), but can likely start as hot tap water.
 
maybe can go with a heat tape on the piping coming from the tank outlet to the pump, then have a bypass valve back to the tank in a "T" fitting with an outlet valve.
 
papa_smurf said:
maybe can go with a heat tape on the piping coming from the tank outlet to the pump, then have a bypass valve back to the tank in a "T" fitting with an outlet valve.
Click to expand...
This will have to be a small, self-contained setup, so I'm trying to avoid any type of metallic piping to minimize risk of fire/burns.
 
some_kid6 said:
The one I linked has a cold input and hot output so it should do what you want as long as you put things in the right order.

Here's my engineering schematic:

View attachment 686050

Edit: nvm you'll need a tankless heater like this
Click to expand...
Those instantaneous things have terrible temperature regulation and power is too high. Get a $25 fountain pump and that RV heater but the RV heater uses all the capacity of a house receptacle
 
Just as a follow-up to this, ended up not needing to go this route. We were able to find someone who spec'd and imported these out of Atlanta and drove down there Saturday to pick up a complete solution.

Long story short, this was for a recirculating sink that is used with a spray bar attachment that is part of a hair/facial massage bed deal. You fill the sink, and it recirculates water through a heater and spray bar for the better part of an hour until the treatment is done, and then it gets pumped into a drain. My wife runs a small hair salon in the Charlotte area and there is a huge demand for this service among the clientele looking to get pampered. So she'll get to sit down and have her arms at waist height, which will be a huge quality of life improvement since doing hair has wrecked her neck/back/shoulders over the years.

Since we don't have a floor drain in her suite, I will only need a basic pump for emptying the "sink" now, not one that is capable of recirculating or heating. I still need to find a clever way of teeing off the shutoff valves under the separate sink and running lines to feed the massage bed without making it look like crap.
 
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Dang, I was about to get a salesman in contact with you and get this system installed.

We'd set you up with a server and network engine along with the system controller. Install a domestic water heater with a 3 way valve for temperature reset. Some software and database work, a graphical HMI, bing bang boom...
 
Frack N Cylons said:
Dang, I was about to get a salesman in contact with you and get this system installed.

We'd set you up with a server and network engine along with the system controller. Install a domestic water heater with a 3 way valve for temperature reset. Some software and database work, a graphical HMI, bing bang boom...
Click to expand...
You sound like one of my company's "customer interface" personnel, complete with 250% markup!

The one thing I will have to figure out is how to neatly run supply and drain lines out of the way. I need to see where my wife wants this thing oriented in her shop. I think I can put a grey water sink adapter with an inline pump to handle the discharge into a 3 way fitting like you'd use for a dishwasher to handle that, and maybe a pair of long flex lines with a tee adapter for the supply lines. Need to route them in such a way that they're not a trip hazard, and don't block wherever my wife is sitting. This is a rental unit, and they will not let her add additional supply or drain lines.
 
Supermatch said:
"customer interface" personnel, complete with 250% markup!
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Gotta feed the machine.

Fortunately I just take what the salesman thinks he sold, what the customer thinks they bought, and what the engineer thinks they designed and try to make it all go.

I kid, it's a team effort.

Sounds like a fun project.
 
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