[lawngilander]

Originally Posted by djlnc

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

I currently have to run the water at the bathroom faucet for 30 sec. or more to get hot water. That’s a lot of wasted water. I could install a POU heater, but I’m not sure that would help. Was just curious if anyone else had done this.

[retiredguy123]

Originally Posted by lawngilander

I currently have to run the water at the bathroom faucet for 30 sec. or more to get hot water. That’s a lot of wasted water. I could install a POU heater, but I’m not sure that would help. Was just curious if anyone else had done this.

I am a little rusty, but here is the math. The wasted water is the cold water that is sitting in the underground pipe that needs to travel through the shower head before the hot water arrives. Assume the pipe size is 3/4 inches in diameter and the water heater is 50 feet from the shower.

Area of the pipe cross-section is "Pi x radius squared" or 3.14 x 0.375 inches x 0.375 inches = 0.4416 square inches.
Volume is 50 feet x 12 inches x 0.4416 = 265 cubic inches.
In gallons, that is 0.00433 cubic inches per gallon x 265 = 1.15 gallons of wasted water

I invite anyone to check my math.

[JMintzer]

Originally Posted by retiredguy123

I am a little rusty, but here is the math. The wasted water is the cold water that is sitting in the underground pipe that needs to travel through the shower head before the hot water arrives. Assume the pipe size is 3/4 inches in diameter and the water heater is 50 feet from the shower.

Area of the pipe cross-section is "Pi x radius squared" or 3.14 x 0.375 inches x 0.375 inches = 0.4416 square inches.
Volume is 50 feet x 12 inches x 0.4416 = 265 cubic inches.
In gallons, that is 0.00433 cubic inches per gallon x 265 = 1.15 gallons of wasted water

I invite anyone to check my math.

[keepsake]

I'm talking about a Junior model. I've never seen one. But like a 1200 watt 120v unit that does smaller volumes of water on a single sink basis. So wait is seconds.

[chvlt57]

Doing the same investigating; time to replace the 16 yr old tank WH. Contacted Teco and found out the cost for an 8.4 GPM is $1600 over 5 years, (no interest), plus any additional gas line extension costs. Providing a dedicated 110 line will also be at the homeowner's expense.
I was surprised to learn that the unit will be placed outside to save venting costs, this is of course not an option where we came from. Outdoor units are more expensive but changing the venting through the roof is also costly.
Looking for some bids other than through the Teco approved plumber in case anyone has a referral. Also what brands and size do most use? Are there currently any tax/energy rebates available?

[maistocars]

Installed a recirculating pump last December on hot water tank. Best $490 I ever spent. Instant hot water throughout house (new Courtyard Villa). Has timer to turn off at night or off switch while away. Took about 45 minutes to install by Mike Scott Plumbing.

[keepsake]

Just saw this ...
https://images.thdstatic.com/catalog...742ddd315a.pdf
120 volt 12 amp 1440 watt
Home Depot $199
4 tank sizes

[Rheinl271]

The tankless heaters are two stage based on flow demand. With just the shower running likely with flow restrictor it will take two minutes at least to get hot. Heater runs on low output. If you run two faucets in the bathroom, the heater kicks in to high output and you get hot water in 30-40 seconds. Plumber explained how it works.

[retiredguy123]

Originally Posted by Rheinl271

The tankless heaters are two stage based on flow demand. With just the shower running likely with flow restrictor it will take two minutes at least to get hot. Heater runs on low output. If you run two faucets in the bathroom, the heater kicks in to high output and you get hot water in 30-40 seconds. Plumber explained how it works.

Note that, even if you just have the regular tank type water heater, you can reduce the time to get hot water by more than half by just turning on a hot water faucet and the shower at the same time. It greatly increases the flow rate to the bathroom.

[retiredguy123]

Originally Posted by keepsake

Just saw this ...
https://images.thdstatic.com/catalog...742ddd315a.pdf
120 volt 12 amp 1440 watt
Home Depot $199
4 tank sizes

If you plan to use the existing electrical outlet in the bathroom to power one of these heaters, I think that you may have issues with the circuit breaker tripping whenever you try to use any other electrical device.

[Villages Kahuna]

It will be the best thing you ever did. I’ve had instant tankless water heaters exclusively in homes in the Chicago area, Michigan, and here in The Villages. They are the GREATEST!

[Hape2Bhr]

Originally Posted by retiredguy123

Note that, even if you just have the regular tank type water heater, you can reduce the time to get hot water by more than half by just turning on a hot water faucet and the shower at the same time. It greatly increases the flow rate to the bathroom.

My electric toothbrush runs about 2 minutes; I turn on the hot water while brushing and rinse the sink with it. When I am done I have hot water at the shower.
We ran six of these in our laundromats. They are paired in groups of three with a program control board for each three that communicate with each other, so each heater is used equally. All units are indoor as is the unit in our courtyard villa.

[Bellavita]

WE had one put in 2013 and I love it more room in the garage and plenty of hot water


.

Originally Posted by lawngilander

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.

[Dave951]

The OP said instant hot water heater. This type of heater would typically be installed under a kitchen cabinet so you have instant hot water for the faucet and dishwasher a tankless heater is gor the whole house

[ldj1938]

Originally Posted by Battlebasset

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.

Put in a recirculation pump. Should be standard for all hot water systems. Pump from heater to furthest sink. Near instant hot water.