Beware of Tankless Water Heaters

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Chuck Fowler
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Re: Beware of Tankless Water Heaters

Post by Chuck Fowler »

Steve Collins wrote:But doesn't a "no return" style system make your cold-water hot? So you trade waiting on hot-water for waiting on cold-water?

sc
turn on the pump and open the cold water tap to remove warmish cold water :lol:
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Re: Beware of Tankless Water Heaters

Post by George Schilling »

Steve Collins wrote:But doesn't a "no return" style system make your cold-water hot? So you trade waiting on hot-water for waiting on cold-water?

sc
Water on the cold side is luke warm for the first few moments. It's typically not a problem since most don't want "cold" water in the bathroom. But by the time you're ready for a cold drink, it's there.
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Re: Beware of Tankless Water Heaters

Post by Ashley Armstrong »

Moving into a 700sqft 1br/1ba in July with very little storage. The only large cabinet in the kitchen area is filled with a water heater tank, and I'd really rather have a pantry in that space. My mind went right to this thread!
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Re: Beware of Tankless Water Heaters

Post by Rick Brown »

Eric Clements wrote:http://www.grundfos.com/web/HomeUs.nsf/ ... MAT-6DMQV8

I've installed a couple hundred of these. They work great. Doesn't work with tankless, will increase gas useage, will decrease water useage.
My water heater is electric, but wouldn't it be more expensive in either case? Gas & electricity are more expensive than water aren't they? My water bill is only $13 a month.
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Re: Beware of Tankless Water Heaters

Post by George Schilling »

Ashley Armstrong wrote:Moving into a 700sqft 1br/1ba in July with very little storage. The only large cabinet in the kitchen area is filled with a water heater tank, and I'd really rather have a pantry in that space. My mind went right to this thread!
Hi Ash. As long as your water is soft, you could consider it, but there are other limitations/problems to consider. Give me call and I'll fill you in.
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Re: Beware of Tankless Water Heaters

Post by Ashley Armstrong »

George Schilling wrote:
Ashley Armstrong wrote:Moving into a 700sqft 1br/1ba in July with very little storage. The only large cabinet in the kitchen area is filled with a water heater tank, and I'd really rather have a pantry in that space. My mind went right to this thread!
Hi Ash. As long as your water is soft, you could consider it, but there are other limitations/problems to consider. Give me call and I'll fill you in.
Thanks George! I'll give you a shout after we move in--I don't know anything about the water yet.
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Re: Beware of Tankless Water Heaters

Post by Thomas Smith »

George

I own the typical 1500 sqft Lakewood house built in 1946. My water heater is located in my laundry room and if it burst and flooded the house my hardwood floors would be ruined. I've considered getting a gas tankless for peace of mind as much as anything. I don't really care about energy savings as my gas bill is pretty reasonable. I mention the burst water heater because it happened at my parents house years ago and luckily only flooded the basement and garage. How often should water heaters be replaced? Will a smitty pan with a drain to the outside be able to deal with a burst water heater?

Thanks
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Re: Beware of Tankless Water Heaters

Post by George Schilling »

Thomas Smith wrote:George

I own the typical 1500 sqft Lakewood house built in 1946. My water heater is located in my laundry room and if it burst and flooded the house my hardwood floors would be ruined. I've considered getting a gas tankless for peace of mind as much as anything. I don't really care about energy savings as my gas bill is pretty reasonable. I mention the burst water heater because it happened at my parents house years ago and luckily only flooded the basement and garage. How often should water heaters be replaced? Will a smitty pan with a drain to the outside be able to deal with a burst water heater?

Thanks
The smitty pan piped outside will handle any normal water heater leak. Water heaters are glass lined. Imperfections in that glass lining leads to rust through in the metal tank in the form of pin hole leaks. As long as you have an operable temperature and pressure relief valve to protect against accidental over-pressurization, a tank won't fail catastrophically. Without this valve, the tank is capable of over pressurization with super heated water. This failure is very unlikely in gas fired tanks, more likely in electric water heaters. If the pressure is not relieved, the superheated water could cause the bottom of the tank to blow out turning the water heater into a missile. I remember an electric water heater in Bellflower a few years ago that was mounted below the stairs on the bottom floor of a three story townhome. It blasted right through the roof. Here's an example.

http://www.youtube.com/watch?v=pu3FwgIHsQA" onclick="window.open(this.href);return false;

Oh, BTW, the T & P drain line should be piped to a safe location separate from the pan and drain to a flower bed or driveway outside you home. Remember that water coming out of this pipe could be as hot as 210 degrees. Ouch.
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Re: Beware of Tankless Water Heaters

Post by Thomas Smith »

George Schilling wrote:
Thomas Smith wrote:George

I own the typical 1500 sqft Lakewood house built in 1946. My water heater is located in my laundry room and if it burst and flooded the house my hardwood floors would be ruined. I've considered getting a gas tankless for peace of mind as much as anything. I don't really care about energy savings as my gas bill is pretty reasonable. I mention the burst water heater because it happened at my parents house years ago and luckily only flooded the basement and garage. How often should water heaters be replaced? Will a smitty pan with a drain to the outside be able to deal with a burst water heater?

Thanks
The smitty pan piped outside will handle any normal water heater leak. Water heaters are glass lined. Imperfections in that glass lining leads to rust through in the metal tank in the form of pin hole leaks. As long as you have an operable temperature and pressure relief valve to protect against accidental over-pressurization, a tank won't fail catastrophically. Without this valve, the tank is capable of over pressurization with super heated water. This failure is very unlikely in gas fired tanks, more likely in electric water heaters. If the pressure is not relieved, the superheated water could cause the bottom of the tank to blow out turning the water heater into a missile. I remember an electric water heater in Bellflower a few years ago that was mounted below the stairs on the bottom floor of a three story townhome. It blasted right through the roof. Here's an example.

http://www.youtube.com/watch?v=pu3FwgIHsQA" onclick="window.open(this.href);return false;

Oh, BTW, the T & P drain line should be piped to a safe location separate from the pan and drain to a flower bed or driveway outside you home. Remember that water coming out of this pipe could be as hot as 210 degrees. Ouch.
Thanks George. I just took a look and my T&P valve simply points down with no drain piping. There's also never been an earthquake strap on my water heater. The water heater was installed by the previous owner of my house who is a plumber! I think I found my next home improvement project.....
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Re: Beware of Tankless Water Heaters

Post by Steve Ekstrand »

AP-Gaza City

Hamas leaders have announced a new ballistic missile capability that will allow them to deliver a dirty bomb warhead to Tel Aviv. The missile dubbed the Whirlpool Flame Lock 50 gallon has an unknown range and payload capacity, but makers claim an annual savings of $379 on your average gas utility billing. Israeli officials declined to comment.
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Re: Beware of Tankless Water Heaters

Post by George Schilling »

Thomas Smith wrote:
George Schilling wrote:
Thomas Smith wrote:George

I own the typical 1500 sqft Lakewood house built in 1946. My water heater is located in my laundry room and if it burst and flooded the house my hardwood floors would be ruined. I've considered getting a gas tankless for peace of mind as much as anything. I don't really care about energy savings as my gas bill is pretty reasonable. I mention the burst water heater because it happened at my parents house years ago and luckily only flooded the basement and garage. How often should water heaters be replaced? Will a smitty pan with a drain to the outside be able to deal with a burst water heater?

Thanks
The smitty pan piped outside will handle any normal water heater leak. Water heaters are glass lined. Imperfections in that glass lining leads to rust through in the metal tank in the form of pin hole leaks. As long as you have an operable temperature and pressure relief valve to protect against accidental over-pressurization, a tank won't fail catastrophically. Without this valve, the tank is capable of over pressurization with super heated water. This failure is very unlikely in gas fired tanks, more likely in electric water heaters. If the pressure is not relieved, the superheated water could cause the bottom of the tank to blow out turning the water heater into a missile. I remember an electric water heater in Bellflower a few years ago that was mounted below the stairs on the bottom floor of a three story townhome. It blasted right through the roof. Here's an example.

http://www.youtube.com/watch?v=pu3FwgIHsQA" onclick="window.open(this.href);return false;

Oh, BTW, the T & P drain line should be piped to a safe location separate from the pan and drain to a flower bed or driveway outside you home. Remember that water coming out of this pipe could be as hot as 210 degrees. Ouch.
Thanks George. I just took a look and my T&P valve simply points down with no drain piping. There's also never been an earthquake strap on my water heater. The water heater was installed by the previous owner of my house who is a plumber! I think I found my next home improvement project.....
Tom, if you want your install to be to code, the t & P drain line needs to be copper, steel or CPVC piping. No PVC. You can use PVC for the smitty pan drain.
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Re: Beware of Tankless Water Heaters

Post by Bob Beamesderfer »

Steve Ekstrand wrote:AP-Gaza City

Hamas leaders have announced a new ballistic missile capability that will allow them to deliver a dirty bomb warhead to Tel Aviv. The missile dubbed the Whirlpool Flame Lock 50 gallon has an unknown range and payload capacity, but makers claim an annual savings of $379 on your average gas utility billing. Israeli officials declined to comment.
Forget about car bombs!
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Re: Beware of Tankless Water Heaters

Post by Rick Brown »

George Schilling wrote: I remember an electric water heater in Bellflower a few years ago that was mounted below the stairs on the bottom floor of a three story townhome. It blasted right through the roof. Here's an example.

http://www.youtube.com/watch?v=pu3FwgIHsQA" onclick="window.open(this.href);return false;
The high speed camera stuff is very cool. Do these guys have the best job on the planet or what?
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