Instant hot water heaters
 

Would like to install an instant hot water heater on my small (1150 sq. ft.) Patio Villa. Have you done this?
What were your results. Also considering a POU water heater.

We had one installed and love it. Takes a short time for the hot water to get to the bth faucet. Happy we did it.

My opinion, they are not instant, not even close. They are endless though, if that is important to you. We had no choice on our house. We solved the time element problem but it cost another $3k .

Our home came with one. Our shower is located at the most remote point from the heater. We run a solid two gallons before the water is hot enough to step into. It does save room in your garage as it mounts on the outside of your house.

We have learned to start the dishwasher or washing machine to clear the cold water in the pipes and "wake up" the tankless heater. We catch the first two gallons in a five gallon bucket and use it to flush toilets and water plants/grass.

Overall, I'm OK with it, but it's a bit annoying. I was always amazed when someone up north got one. I thought "that is going to take forever to warm up".

Also, you will need to set at least at 130 degrees. At the standard 125 the water will be too cold by the time it reaches you most remote point in your house.

Heater
 

Make and model of unit?

Why not just replace the tank type heater? Easier, cheaper, less maintenance, and more repairable. Have you checked into any additional electrical modifications you would need to make to your house?

Unless you can somehow run a return line for recirculating it will just be a tankless water heater. When our house was built we had a recirculating heater installed with the return line. It is instant through most of the house but takes about 20 seconds to get hot in our outside kitchen.

Replacing a Tank hot water heater with a tankless in a home can be expensive becasue if you are using electric a new electric line of higher capacity has to be installed or of you are using gas, the gas line has to be run to the tankless heater.

The only way to get hot water to your faucets, etc at the far side of the house is to install a circulating pump that's controlled by a timer and use a wifi plug and control it via google or alexa. The pump can be installed by DIY'er but i recommend getting a plummer or HVAC professional to do the install. There are several on the market designed just for this purpose. Once done you can purchase a Wifi plug where you can turn on and off the circulator pump when you need hot water. So for example if you want to take a showe you say something like "google turn on the water heater pump for 5 minutes" and you will have hot water by the time you get into the shower. When using this method the timer on the circulating pump needs to be set to ON all the time. This is the best way i've found to manage the circulating pump because using a timer to turn it on and off means you have to be using hot water every day around the same time.

Having never owned one, this is hearsay, but I recall years (a lot of years) ago that the tankless heaters did supply an endless supply of hot water but at a pressure significantly lower than the tank types. Maybe they've changed since then.

The house water pressure is going to be the same whether or not you are using the water heater. When you are using the shower, the hot and cold water are being mixed, so, if your house pressure is 60 psi, that is what you will get at the shower and the faucets.

If you remove the flow restrictor from the shower head.

What do you mean by an "instant hot water heater"? A tankless heater? What do you want to accomplish?

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Why? Water still has to get from the heater to the faucet. Consider a circulating pump if you want how water when you turn on the faucet. You should use a timer to turn on and off. The cold water line is the return route so you will lose cold water when the pump is on.

What I would buy would be an 'instant heater' right under each sink. One that runs on just 120 volts that is right there. And yes use the 1/4" piping. No wait and not the 60 amp breaker need.