| Brass Temperature & Pressure Relief Valves for Water: |
| 1/2" with 150psi, standard style |
$12.95 |
| 1/2" with 150psi, with extra long probe style |
$15.95 |
| 3/4" with 125psi, standard |
$11.95 |
| 3/4" with 150psi, extra short probe style |
$13.93 |
| 3/4" with 150psi, extended shank - 2 1/2" |
$13.95 |
3/4" with 150psi The "standard" one
Order 10 or more for greater savings! |
$10.95 |
| 3/4" with 150psi, extra long probe style |
$15.90 |
| 3/4" with 150psi, (up to 200,000 BTU) |
$74.33 |
| 3/4" with 175psi, standard length |
$11.95 |
| 1" with 150psi, (up to 500,000 BTU) |
$69.56 |
"Why would anyone need an expansion tank?"
Water is incompressible. Unlike air, it's impossible to squeeze any quantity of water into a smaller volume.
Where that matters is in "closed" water systems such as a water heater with a check valve (pressure regulator and the like)
ahead of the heater. When the water gets heated it expands and that extra volume has to go someplace. Without an expansion
tank the pressure could rise to a dangerous level in a closed system. A diaphragm type of expansion tank (such as what we sell)
is a pressure vessel that contains a flexible membrane totally separating the water from a captive volume of air. Air compresses
and as the water temperature rises, creating extra pressure/space, the air in the vessel accommodates that increase. Thereby preventing
a potentially dangerous pressure rise.
"Why is there a hole near the top of your diptubes?"
The reason for the hole is to break siphonage effect when the water is shut off and there is a drain down situation (caused by
such things as a valve or a leak that is below the waterheater). A common example would be in a mobile home water heater, where the water supply
is nearly almost always under the floor. If the water gets shutoff (for whatever reason), without that hole, the diptube could possibly backsiphon
(empty most of the water and drain it to the level of the inlet on the cold water diptube),
burning up the elements or possibly allowing the gas burners to damage the near empty water heater. Bottom line, it's for safety.
"I have a rattling sound coming from my water heater when the hot water is running?"
Check to see if you have check valve type nipples installed on the top of your water heater.
They generally look like ordinary galvanized nipples and so sometimes it is
hard to tell if they are installed. Some water heaters come with them. They are
a great idea because they can save some energy, but they also can be very annoying.
"I am looking for 120V water heater I can install under my kitchen sink. I
need one that will provide about one sink-full of hot water on demand (It
currently takes about 60-80 seconds to get hot water to the sink). Will your above undercounter water heaters work for me?"
Yes, the 2.5 gallon "should" just be "perfect" for your situation. It holds 2 1/2 gallons and when mixed with cold water
would give you over 4 gallons of mixed warm water which is plenty for almost all residential sinks.
We like to recommend these for under the kitchen sink and for your "cold" inlet you can use your hot water supply.
"I've read that microwaving hot water can be dangerous?"
Water and other liquids, when heated in a microwave, do not always bubble when they reach the boiling point. They can actually get superheated and not bubble at all. The superheated liquid will bubble up out of the cup when it is moved or when something like a spoon or tea bag is put into it.
To prevent this from happening and causing injury, do not heat any liquid for more than two minutes per cup. After heating, let the cup stand in the microwave for at least thirty seconds before moving it or adding anything to it.
Here is what our local science teacher had to say on the matter: "Thanks for the microwave warning. I have seen this happen before. It is caused by a phenomenon known as superheating. It can occur anytime water is heated and will particularly occur if the vessel that the water is heated in is new, or when heating a small amount of water (less than half a cup).
This is caused by the water heating faster than the vapor bubbles can form. If the cup is very new, it is unlikely to have small surface scratches inside it that provide a place for the bubbles to form. As the bubbles cannot form and release some of the heat that has built up, the liquid does not boil, and the liquid continues to heat up well past its boiling point.
Then, what usually happens is that the liquid is bumped or jarred, which is just enough of a shock to cause the bubbles to rapidly form and expel the hot liquid. The rapid formation of bubbles is also why a carbonated beverage spews when opened after having been shaken.
