44 votes
Accepted

Why does this pipe feeding a hot water heater dip down like this?

It is highly likely that that piping arrangement is made that way to facilitate the installation of a water softener. A water softener will have a need to accept a pipe with incoming hard water and ...
  • 62.4k
44 votes
Accepted

How to drill through wall without hitting boiler on the other side

Buy a drill stop to screw onto your bit, and set it to the thickness of the wall. Some drills also have a built-in stop that can be adjusted. If you don't know the thickness of the wall, then just ...
  • 3,402
30 votes
Accepted

Are water boilers dangerous when showering?

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 ...
  • 529
30 votes

I ran out of propane and now the water heater pilot light will not stay lit

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 ...
  • 101k
28 votes
Accepted

How do electric hot water heaters explode and what can be done to prevent that from happening?

Yes, that's a scary article but keep in mind that both safety devices have to fail to have the tank explode. The pressure release valve and the high limit on the thermostat both have to malfunction. ...
  • 67.1k
28 votes
Accepted

Turn off hot water without hot water valve

My approach would be to turn off the water heater and the cold supply. Then open a hot tap below, or as close to the area of the leak, to drain the hot pipe. Then be prepared to catch the remaining ...
  • 23.5k
26 votes
Accepted

Is my plan for fixing my water heater leak bad?

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 ...
  • 12.3k
25 votes
Accepted

Can filling up a 75 gallon water heater tank without opening a faucet cause damage?

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,...
  • 6,865
25 votes

Can tankless & conventional water heaters join forces?

I see a couple problems there. First, having a tanked heater operate at less than 140°F (60°C) is problematic. The reason is our science has advanced on the Legionella bacteria which causes ...
25 votes

How to drill through wall without hitting boiler on the other side

Don't. You'll ruin the cable. As Nelson points out in the comments, CAT5 cables have a turning radius of 1 inch to avoid damage to the cable. In a scenario where the boiler is only 2cm from the wall, ...
25 votes

Could my water heater in a 4 unit townhome be shared and explain my high power bill?

If you are paying for electricity, there must be an electric meter somewhere. The electric meter has wires (possibly inside a pipe) that feeds an equipment panel which has circuit breakers in it. If ...
24 votes

Why do gas water heater exhausts have an air gap before the chimney?

The actual amount of combustion air - i.e., air flowing past the burner to provide oxygen and leave with less oxygen but more CO2 and possibly other combustion byproducts - is very little. The gap ...
24 votes

How do electric hot water heaters explode and what can be done to prevent that from happening?

Consider the sources; it is plumbers giving you a scare story to get you to hire them. See also "aluminum wiring". It will take a chain of 3 events at once: failure of the thermostat, causing ...
23 votes

Are water boilers dangerous when showering?

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 ...
  • 19.6k
23 votes

Any special precautions when turning off water to a property?

In addition to what FreeMan stated, if you have an electric water heater you want to turn off the breaker that feeds it. Depending on your plumbing, turning on some hot water faucets to finish some ...
  • 67.1k
19 votes

Can filling up a 75 gallon water heater tank without opening a faucet cause damage?

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 ...
  • 12.3k
19 votes
Accepted

Water leaving the house when water cut off

Three things here. First: since you self-installed it sounds like you might have missed the vacuum break. Here is some brief discussion of why it is required by the Universal Plumbing Code. ...
  • 3,743
18 votes

How high to raise water heater above floor?

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 ...
  • 13.1k
18 votes

Why is water running into my water heater when cold water inlet is turned off?

This is because after turning off your water you still have water in the pipes. The water heater in most houses is at one of the lowest points in the house. Meaning that even after turning off ...
  • 46.9k
18 votes

How can we dry out a soaked water heater (and restore a novice plumber's dignity)?

If you have a wet vacuum cleaner with a slotted attachment, use that first to suck up pooling water and very wet insulation. Then pull out as much of the wet insulation around both elements as you can....
  • 67.1k
17 votes

Can I use existing 30 amp wiring that was serving a traditional water heater for an on-demand WH that requires 40 amps?

No, of course not. You need new wiring and new breakers. Or you need to return the new water heater for one that fits your available power supply. See NEC Article 220 load-calculation for entire house ...
  • 158k
16 votes

Need to know if tankless hot water system for my new house build is a good option if I only have electric power

The catch with any type of electrical heating element is how fast does it need to come up to temperature? The faster and hotter it needs to be, the more electricity it will use. Electric tank water ...
  • 22k
15 votes

Removing water heater, will I still have the use of my cold water while water heater is disconnected? We are replacing flooring in the room

If the plumber does their work correctly, yes. Typically, there should be a shut-off valve just for the water heater. They would turn off water to the water heater, then work on it (after capping the ...
  • 1,892
14 votes

Any special precautions when turning off water to a property?

I've turned the water off at the meter for our house more than once - I even bought my own "curb key" to do it. We've had a small variety of leaks and issues requiring this. The water ...
  • 35.1k
14 votes

How to maximize hot water production given my electrical panel limits on available amperage?

Given the details from all the chatter in your comments, I see four practical solutions: Install a conventional 55 gallon electric or heat pump 80 gallon tank with an added tempering valve. Set the ...
  • 3,743
13 votes

I ran out of propane and now the water heater pilot light will not stay lit

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 ...
  • 535
13 votes

Is my plan for fixing my water heater leak bad?

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 ...
  • 6,156
13 votes
Accepted

Why do gas water heater exhausts have an air gap before the chimney?

This is a draft diverter. If the heater was connected directly to the chimney, the hot flue gas would rise, creating draft in the heater. While that is a good thing, the amount of draft would depend ...
13 votes

Is it safe to shut off an electric water heater for long periods of time?

All hot water heaters already have a regulator. Otherwise the water would boil over and you'd have a boiler explosion. You can feel free to shut off an electric water heater for an extended period of ...
12 votes

Why do gas water heater exhausts have an air gap before the chimney?

manassehkatz covered a lot, but the simple answer is constant air flow The draft will change in the chimney as exhaust vents towards it – especially when going from cold air to hot. A draft hood is ...
  • 22k

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