Tankless Water Heaters (Pittsburgh: credit, hotels, home)

[Hopes]

My water heater is leaking. I'm considerng a tankless water heater. It's more expensive than a traditional water heater, but there is a constant supply of hot water and it saves energy.

I've been doing some research, and I'm concerned about Pittsburgh winters. Apparently, the colder water gets in the winter, the bigger the unit. I also wonder if a tankless water heater might put my pipes at a greater risk of freezing in the winter. I guess regular water heating doesn't keep the hot water pipes in the walls hot all the time so maybe that's a silly concern.

Does anyone have a tankless water heater? I'm interested in hearing the pros and cons---from a Pittsburgh perspective.

[ditchdigger]

If the cold water pipes to any given room aren't prone to freezing, then the hot water pipes won't be any more prone to freezing, regardless of what kind of hot water tank you have.

[Hopes]

I know for a fact that hot water freezes faster than cold water.

I'm also finding information that nondirect vent models can freeze even if they're installed indoors.

It's a scary decision to go with something unconventional to our area of the country, but I'm very interested.

[Johnny C]

Originally Posted by Hopes

I know for a fact that hot water freezes faster than cold water.

I'm also finding information that nondirect vent models can freeze even if they're installed indoors.

It's a scary decision to go with something unconventional to our area of the country, but I'm very interested.

You would be wrong - cold water freezes faster than hot water, but the urban legend you speak of is based on some misconceptions:

When hot water is subjected to freezing temps it undergoes evaporation, so you are actually freezing less liquid water then if you were to freeze cold water. If you attempt to freeze the same MASS of cold and hot water, the cold water will freeze sooner every time. Put hot and cold water into your freezer and you will find that the hot water freezes sooner but only because some of it evaporates and you are freezing less mass of the hot water due to evaporation. The laws of physics still apply.

That being said, tankless water heaters are ok. but they are much more expensive to buy and install than tank heaters and take years to offset the initial cost of purchase. Also,tankless water heaters have a certain "delay" time when you turn on the faucet that takes some getting used to. I still like the tank heaters for value, but the tankless heaters are ok if you are willing to deal with their quirks and cost.

[Hopes]

Originally Posted by Johnny C

You would be wrong - cold water freezes faster than hot water, but the urban legend you speak of is based on some misconceptions:

When hot water is subjected to freezing temps it undergoes evaporation, so you are actually freezing less liquid water then if you were to freeze cold water. If you attempt to freeze the same MASS of cold and hot water, the cold water will freeze sooner every time. Put hot and cold water into your freezer and you will find that the hot water freezes sooner but only because some of it evaporates and you are freezing less mass of the hot water due to evaporation. The laws of physics still apply.

It still freezes faster regardless of the process. And I did find some information about certain tankless versions that are prone to freezing.

My main concern is using a tankless water heater in the Pittsburgh climate. I've been reading about a reduction of output when the input water is colder in the winter.

I'd hate to install one this month only to find that it doesn't serve us well in the winter.

Originally Posted by Johnny C

That being said, tankless water heaters are ok. but they are much more expensive to buy and install than tank heaters and take years to offset the initial cost of purchase. Also,tankless water heaters have a certain "delay" time when you turn on the faucet that takes some getting used to. I still like the tank heaters for value, but the tankless heaters are ok if you are willing to deal with their quirks and cost.

The cost isn't much of an issue. Tank water heaters are becoming expensive so the initial cost difference isn't as great. Plus tankless water heaters last longer, cost less to operate, and qualify for federal tax credit of $300.

I think unlimited hot water offsets the time delay. Point of use water heaters eliminate the wait time. I might install more than one system to address that issue. Still it's a huge change. I don't want to spend money installing it only to hate it.

I also want to talk to my heating/cooling contractor. I remember our boiler has a feature for heating tap water, but I think it still stores in a tank.

I'm sick of water tanks and water in the basement when they need to be replaced. They don't last long, but tankless water heaters last 20 years.

[ditchdigger]

It still freezes faster regardless of the process. And I did find some information about certain tankless versions that are prone to freezing.

But it isn't hot water in a tankless until you go to use it, so isn't that a contradiction?

[Heit]

Originally Posted by Hopes

My water heater is leaking. I'm considerng a tankless water heater. It's more expensive than a traditional water heater, but there is a constant supply of hot water and it saves energy.

I've been doing some research, and I'm concerned about Pittsburgh winters. Apparently, the colder water gets in the winter, the bigger the unit. I also wonder if a tankless water heater might put my pipes at a greater risk of freezing in the winter. I guess regular water heating doesn't keep the hot water pipes in the walls hot all the time so maybe that's a silly concern.

Does anyone have a tankless water heater? I'm interested in hearing the pros and cons---from a Pittsburgh perspective.

I have a regular hot water tank with a re-circ pump added into the line right beside the tank. It cost a fraction of a tank-less and gives you nearly instant hot water. We have yet to run out of hot water as well.

The name on our pump is: TACO Cartridge Circulator.

[aveojohn]

Originally Posted by Heit

I have a regular hot water tank with a re-circ pump added into the line right beside the tank. It cost a fraction of a tank-less and gives you nearly instant hot water. We have yet to run out of hot water as well.

The name on our pump is: TACO Cartridge Circulator.

They are also much less energy efficient. There is nothing wrong with Instant (tankless)water heaters and they are very energy efficient, due to the fact they only heat the water when you need it.

[JoeLeaphorn]

Originally Posted by aveojohn

They are also much less energy efficient. There is nothing wrong with Instant (tankless)water heaters and they are very energy efficient, due to the fact they only heat the water when you need it.

In terms of fuel, yes, but if you pay for water and have to wait for it to heat up, you're spilling the rest down the drain. Hotels don't install recirculating pumps for the convenience of the customer, they do it because it saves on their water bills. Of course, the proportional savings for the home maybe less.

As for tankless, if you are going to use a hot tub, soaking tub, Jacuzzi, etc., think carefully about having an auxiliary tank heater for those applicances. My brother-in-law has a large Jacuzzi and it takes a long time to fill it with hot water from his tankless water heater. So much so that they almost never use it.

[Hopes]

Originally Posted by JoeLeaphorn

In terms of fuel, yes, but if you pay for water and have to wait for it to heat up, you're spilling the rest down the drain.

Not if you install point of service water heaters.

Originally Posted by JoeLeaphorn

As for tankless, if you are going to use a hot tub, soaking tub, Jacuzzi, etc., think carefully about having an auxiliary tank heater for those applicances. My brother-in-law has a large Jacuzzi and it takes a long time to fill it with hot water from his tankless water heater. So much so that they almost never use it.

He didn't have a larger water line installed for his Jacuzzi.