40
There are two main and opposing risks:
Too high, and users get scalded
Too low, and you risk pathogens, particularly Legionella bacteria, which causes legionellosis (Legionnaires' disease)
Minimum temperature
Legionella risk
According to the paper "Legionella and the prevention of legionellosis," found at the World Health Organization website, ...
30
I have had similar problems in the past when running out, what I found is I had to hold the pilot for several minutes to get the lines full of propane again. I found it easiest to light the stove top or try until it would burn then I went to the furnace and water heater it still took a few minutes as the pilot is a very small draw but once the lines had ...
29
I'm from Serbia, just like the OP, and we do have such a myth there. After my initial rant, aimed at explaining why some of the safety assumptions that many answers here may have are wrong, I'll show installation of a typical water heater and explain a couple of issues that I see with the installation.
(Feel free to skip this part)
First, some background, ...
26
If the water on the floor is from the water heater I would fix that problem before I do anything else. If it is coming from the tank then it probably needs replaced. You can raise the tank as high as you want but if you do I would also replace the copper flex water lines and the flexible gas line. Once those lines get older, the flex gets hard and rigid and ...
25
I wouldn't worry about it at all. A gallon of water is roughly 213 cubic inches. Assuming that you filled the tank completely (which is unlikely - see below), you would have displaced 213 * 75, or 15,975 cubic inches of air inside your plumbing. One atmosphere of pressure (14.7 psi) is defined as the pressure exerted by a 33.8 ft column of water. Assuming ...
23
If the water heater is not properly grounded, it could be dangerous but then it would be dangerous all the time, not just when you take a shower.
Sounds to me like a myth that got started because someone once was injured by a faulty water heater and then the myth took on a life of its own.
If the water heater is wired properly you have nothing to fear.
...
20
I'd say it's a mark left by the plumber's torch while soldering the copper pipes rather than an electrical problem.
19
The pressure of the air trapped in the system is exactly the same as the water pressure. There is no area for concern pressure-wise.
However, air is much less dense than water, so these problems could occur:
tiny leaks which were clogged by debris might be cleared (unclogged) by air and might introduce a new drip
water surge hammering might shake pipes ...
17
If you have an electric hot water heater, it may mean that one of your two elements has burned out. Most electric hot water heaters have an uppper and a lower element; the upper runs until the top of the tank is hot, which provides quick recovery time, then when the top thermostat is satisfied, it transfers power to the lower thermostat, which heats until ...
17
If you've got a gas water heater, there is a common problem that can occur with certain models. Because of the way they're designed, many have a "dip tube" that sits underneath the cold water inlet. It runs most of the length down the heater and channels incoming cold water down to the bottom of the tank where it can be heated closest to the flame.
If ...
17
Regardless of code, I like to get them off the floor just in case the basement floods. My preferred (and easily available anywhere) solution is a few solid concrete blocks; one under each foot. You can stack them if you want, too. This is an easy way to increase the height in 4" increments.
I don't suggest using lumber. If your floor is the least bit ...
13
There are three reasons a T&P valve opens. Temperature, pressure, or a faulty valve.
Temperature
If the water in the heater reaches a temperature of 210 degrees F, the T&P valve will open and release water until the water temperature is reduced. As water is removed through the T&P valve, cold water enters through the inlet and mixes with the ...
13
My understanding of pilot lights is that they heat a thermocouple, which is a mass of metal that detects heat. The electronics behind that thermocouple will shut off the gas to the pilot if the thermocouple gets cold so that if something blows out the pilot you don't have a gas leak in your home. The side effect is that you have to heat up that mass of metal ...
13
No gas shut off for either line, flex is not suitable for a stationary appliance unless it's approved CSST, duct tape on the flue, draft hood is crooked, pressure relief should terminate in a conspicuous location, those flex lines, globe valve, saddle valve, crooked seismic strap, it's old, it's leaking, plus all the problems not visible from the picture. ...
11
Modern codes generally require 5/8" fire-rated drywall (Type X) between a garage and the living areas of a house. Double check with your local city/county/state as they may have more stringent requirements.
11
After doing a bit of research on what exactly hot water return lines are I found this page which goes into a lot of detail about how they work and their benefits and drawbacks.
The big drawback I see is that you will need to make sure that all your hot water lines are well lagged to minimise the inevitable heat loss that will occur with the hot water ...
11
There is a reason most countries regulate gas-related equipment strictly, because they don't want buildings to explode. If there is no electricity or gas involved, fix it! If it's under - let's say - 50 Volts, go on! If it's 110-230 V, watch out, but you'll be probably okay. If it can leak gas, and fill up the inside of a building, or kill everyone through ...
10
Water heaters have a dip tube on the cold water side that puts the cold water into the bottom of the tank. If water pressure is lost on the cold water side, the tank can siphon down through the cold water inlet till it reaches the bottom of the dip tube. Then since there's no water in the tank to absorb heat, the dip tube can melt and the tank can be damaged....
10
In the UK we have electric showers which heat water on demand - ie they're supplied with 230V using about 9kW, which is enough for a moderate flow of cold water to be heated to about 50C as it flows through the shower.
Not only are they directly connected to the shower hose, they're usually inside the shower cubicle - so the unit gets wet and the electrical ...
10
This happened to me when the water heater in a rental house was replaced by the landlord's "handyman". Check that the cold inlet and hot outlet pipes on the heater weren't installed backwards.
The inlet should have a tube so that the cold water enters at the bottom of the heater. The outlet should pull from the top. That way the cold water pushes most ...
9
This manual for a State Select gas-fired water heater states "Due to the nature of the typical gas water heater, the
water temperature in certain situations may vary up to
30°F higher or lower at the point of use such as, bathtubs,
showers, sink, etc.
This means that when the temperature adjustment dial is
set at the mark approximating 120°F, the actual ...
9
With a tankless water heater it's all about how many degrees the heater can raise a certain quantity of water. In your situation, you will need a heater to raise the temperature of about 5 gallons per minute (two showers running at once or one shower and another hot water tap running). If you live in the north, and the water out of the tap is be 40 degrees ...
9
The drip pan's drain tube may not be large enough to handle the flow if you drain the entire water heater through it, leading to an overflow of the drip pan. I would be safe and use a hose to connect the outlet to the drain.
9
Check out the 1 or 2 gallon point of use heaters that install under the sink. They run on 120VAC and are fairly easy to install with minimal plumbing changes. There are also above sink mounted hot taps that mount into the sprayer hole in the sink. These are usually used for hot water for coffee/tea etc. Both of these type products are available at your local ...
9
How often does your heating system spring a leak? It's not particularly often in my (long) experience with closed-crcuit hot water heating systems - less than once per 20 years, I'd say, and usually with some outside cause. In general, it is a waste of money to remove/replace a system that's working. To address one of your "benefits" - where do you suppose ...
9
The typical way to pre-warm water is to install a standard tank water heater before the tankless, but leave it turned off.
Using an automotive radiator is a terrible idea. You don't want to connect something not designed for potable water to your plumbing. That's just asking for trouble.
The pex idea is interesting. The only reason that I can think that ...
9
Newer water heaters do not last as nearly as long as they used to. Nowadays, you are lucky to get 10 years out of one. This is due to the way they are manufactured.
There are still some water heaters around that are from the 1960s that work perfectly fine. The tanks on some of those heaters are made out of copper, and won't corrode like modern steel tanks.
...
9
Check the manufacturer's installation instructions for the heater. As far as I'm aware, a gas appliance only has to be raised off the floor if there's a possibility of flammable vapors being near it (e.g. in a garage).
IRC P2801.6 Water heaters installed in garages. Water heaters having an ignition source shall be elevated such that the source of ...
9
Answer to Question asked originally
That appears to be unused piping that goes nowhere now. The valves were shutoffs for whatever was that direction. The pipes appear to be capped now, meaning the valves have no function now.
Answer to question as Edited
These pipes and valves still have no purpose. Take the picture you posted to your maintenance people ...
9
There are three things with "thermo" that you need to be aware of. Thermistor, Thermocouple, and Thermopile.
You know what a thermistor is. A Thermocouple generates voltage when its heated, and the voltage varies with the heat. A Thermopile is a collection of thermocouples (in a single package) that generates more voltage.
So, the voltage to open the ...
Only top voted, non community-wiki answers of a minimum length are eligible
