Tankless waterheater
- Thread starter Coonash
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I just installed one and love it. I spent extra money for a new model that included a recirculating pump and timer, but since I was re-piping already, I just added a 1/2" return line. I now have instant hot water from all my faucets, with no water waste at all.
One downside I failed to look at before the installation was the fact that when power goes out, you will have no hot water. Also, in the event of an earthquake, you won't have that extra water available for use. Just something to think about!
schvilktus
New Member
They work fine when sized/installed correctly, and expectations are reasonable. If you want to run 2 showers, wash laundry, and run the dishwasher at one time, you probably won't be happy with the way it works. If you just run 1 shower at a time, and run the dishwasher when you go to bed, you'll probably like it just fine. There are ways to make them work correctly even if you DO run 2 showers at once, but it may take some hot water storage, or multiple tankless units.
The tankless water heater I just installed is a Navien brand, and is natural gas. It has a 1/2 gallon reserve tank and recirculating pump built into it, and is super energy efficient. The exhaust pipes are just PVC pipes, which makes me believe that the heat is contained inside. It also has a stainless steel burner, with a long warranty. It's been about 6 weeks since it was installed, and so far very satisfied with it.
If you are going this route, be sure to do some research on the products.
I would not recommend purchasing the ones from the major home stores for a full house use.
Lowes and Home depot offer units taht are too small for most homes.
Spend some time and make an informed decision on your purchase. expect to spend $800+ for a good one with the ability to support a whole house with 2 baths, d/w w/d, etc.
I would not recommend purchasing the ones from the major home stores for a full house use.
Lowes and Home depot offer units taht are too small for most homes.
Spend some time and make an informed decision on your purchase. expect to spend $800+ for a good one with the ability to support a whole house with 2 baths, d/w w/d, etc.
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BRad704
Moderation
I have looked at these also, but I would be using it for the Master bathroom which is physically as FAR from the main heater as possible! and its on the second floor, so I have no idea where the pipes are... 
Anyone know if its even possible to add on to the middle of the system? I am just looking to get hot water way faster to the master shower...
Anyone know if its even possible to add on to the middle of the system? I am just looking to get hot water way faster to the master shower...
Before changing to a tankless water heater, I purchased a timer controlled water circulating pump, which is a 5 minute addition to my water heater. It then provides a temp. controlled valve for the farthest supply line, which also took less than 5 minutes to install. Once the timer was set, it pushed hot water from the tank thru the lines, and with the temp. valve, returned the hot water back into the tank until it reached its optimum heat. From that point on, I had near instant hot water into by rear bathroom, which is about 70' away from the hot water heater. I purchased from Costco, where they had them for sale on the shelves. Total cost was ~$175, and is called a recirculating water pump. They are also available at most big box hardware stores, and I would give it a "two thumbs up!"
BRad704
Moderation
Great idea havasu! I will have to bring this up to my wife and see if she cares enough to let me have a go at it. My concern is that since I dont know where the hard lines are in the walls, I will have to end up cutting out drywall...
There is no cutting of the water lines. You add the "T" valve directly to the supply line leading from your wall to your faucet. I'm also certain your faucet is on the same leg as your shower, like mine was, and I was able to have a hot shower in less than 5 seconds. In Southern California, water is extremely expensive, and this really helped my water bill. Before the installation, I would turn on the hot water into the shower, and walk away for about 5 minutes, due to my clogged galvanized pipes. That right there was a huge waste of water. I would also set the timer to start pumping between 6 AM and 7 AM, which was when I usually got into the shower before work.
One final note is the fact that a plug must be within 6' of your water heater, since the pump runs on 110 volts. If you have a nearby plug, you are good to go.
One final note is the fact that a plug must be within 6' of your water heater, since the pump runs on 110 volts. If you have a nearby plug, you are good to go.
BRad704
Moderation
but you still had to run an new hardline back from the "T" to the pump, right? Just trying to make sure my mind has all this right....
On my new tankless water heater, I did have to run a return line back to the tank, but the recirculating pump needs nothing more than the return valve, which is about 7" long. It's a 4 way valve. You connect your cold and hot water supply line on one side, and connect included cold and hot water supply lines to your sink. This creates the valve necessary to push the tepid hot water back through the cold water line, creating a recirculated system.
BRad704
Moderation
OOOHHHHHH>...... NOW i get it...
But what happens when you want instant cold water? you have to wait?
If I want instant cold water, I go to the refrigerator! All kidding aside, the cold water line never got hot, just luke warm for a bit. I still have a hard time understanding how or why it worked so well, but it was a great addition.
BRad704
Moderation
I guess its not like there is 160F water in both your pipes from start to end... you are just forcing the hot water (now semi-hot from sitting in the pipes) around to the cold line. Thus getting water from your water heater further into the hot pipe by the time you turn on the hot water... I think I could like with lukewarm water to brush my teeth, as long as my shower didnt take 5 minutes to get warm anymore.
You really need to do your homework before going tankless. Not all units are the equal or the same quality. I hear good things about Rinnai. Know what the warranty requires. Some need to be installed by a Pro. I read about people increasing the water line size to 3/4" before and after the unit since most have 3/4" inlet and outlets. Not sure if this would be kosher as far as a warranty. Realize that many Plumbers will install them, but will not do maintenance or repairs since they are state of the art units. If you have hard water or high minerals, forget tankless. The tubing in them is small and will clog easily. As for circulating pumps, I think the best thing is a point-of-use switch. Installed at the furthest fixture from the heater, you push the button before using the water and the pump activates. This means the pump is not continuously running while no water is being used. Just some thoughts.
You are very correct about doing your homework when deciding on a tankless heater. The one I just purchased has a built in filter, which can be cleaned in 5 seconds. So far, we have run both showers and the washing machine all at the same time, with no loss of heat, just a little loss of pressure. I just received my first natural gas bill today since the installation, and is down about 15%. With the freezing Southern California weather we have been experiencing (got down to 45 degrees once last month, woo hoo!) it is still hard to judge accurately.
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one of the most common misunderstandings is that people think a tankless heater provides instant hot water. Not true! Your tankless heater supplies you an endless supply, until the power goes out, of hot water. I dont recommend the electric ones as most require more power upgrades to feed a whole house than most people in a residential home. Not to mention you could blow dry your hair at the meter base it will be spinning so fast. Also one of the big benefits of a tankless heater is you dont pay to heat water that you are not using while you arent home, or in a no flow situation. I would think a circulating system would cause the heater to fire more than needed which counteracts the whole heating process causing it to heat more than what is needed. It could be done but just doesnt seem cost effective. I will have to look into this setup to be sure so dont hold me to it.
Grundfos makes a retro-fit style recirculation system as the other guys are describing that is cheaper than a tankless heater and I have heard several good reviews.
Grundfos USA
Hope this helps. I dont claim to be right just my $.02
Grundfos makes a retro-fit style recirculation system as the other guys are describing that is cheaper than a tankless heater and I have heard several good reviews.
Grundfos USA
Hope this helps. I dont claim to be right just my $.02
The circulating pump timer is broken down to 15 minute segments. I have my pump turn on twice a day, when hot water is needed. This is good for people who shower at the same time of the day, or wash dishes at a certain time. Yes, if a shower is needed when the pump is not activated, then you will wait about 2-3 minutes for hot water.
Thanks havasu. I didn't realize you were running a timer on your recirc. Makes a little more sense to me now. Basically it just comes on twice a day to try an accomodate the user at That pre selected times each day. Not a bad idea. Still not over heating a lot of water.
