Q: My natural gas, 40-gallon water heater discharges about a quart or quart and a half of water from the relief tube every day. This seems to happen when the water heater turns itself on to heat the water, and has been going on since we had our bathrooms remodeled.
At the time of the first bath remodeling, the plumbers installed plastic pipe; measured the water pressure, which they said was a little higher than normal; and installed a new relief valve and dip tube in the water heater. This increased the available hot water, but I noticed that small drips of water were now discharging from the relief tube. During the second bath remodeling, the plumbers installed a circulating pump at the water heater to ensure fast hot water, and again replaced the relief valve. In addition, they installed a water heater safety tank, which they said would compensate for any fluctuations in water pressure and stop the water discharging through the relief valve. This seemed to solve the problem for a while, but it’s returned.
Bottom line is, when the circulating pump is operating and the water heater cycles on to heat the water, about a quart or a quart and half discharges from the relief tube. Can you give me some possible solutions? –Tom L.
A: It definitely sounds like the problems you are having are due to thermal expansion in the water heater. As the water heats up in the tank, it expands. Since water cannot be compressed, the expanding volume of water has nowhere to go, so it drips out of the pressure relief valve. You also indicated that recent remodeling has increased the water pressure, so this is going to add to the problems. You have had to have two new pressure relief valves installed, which is also an indicator of too much pressure. A pressure relief valve is a safety mechanism and isn’t intended for continuous or repeated use, and all the water going through it can cause mineral buildups in the valve that can affect its performance.
The solution is a thermal expansion tank, which is a small tank filled with air that is mounted on top of or adjacent to the water heater. Pressurized water can enter the tank and will compress the air inside, giving the water a safe place to expand into.
I am assuming that at least one of the plumbers you talked to has already addressed this, and it sounds like the extra safety tank that you mentioned having installed is what I’m referring to. If that’s the case, I would think that the tank is not properly sized to your system, or else it’s defective. The fact that it solved the problem for awhile reinforces my thinking here.
In addition to resizing and replacing the tank, I would also suggest a seven-day timer on your circulating pump. The timer allows you to set the pump to come on at the times of most demand — from 6 a.m. to 8 a.m. for morning showers, for example — and to not be on at times where demand for hot water is low. This saves you energy on the operation of the pump, since the pump is on only when you really need it, and should also help with decreasing the continual pressure in the system.
Q: I need to purchase a new cooktop. I have ceramic tile counters, and the existing area seems to be cut out about 1 to 1 1/2 inches larger than most new cooktops. Is there a way this can be modified? –Lily I.
Not really, unless you have some of the original tile available. You can make the opening smaller using a contrasting tile or an insert of Corian, stainless steel or other material, but anything you do is going to look pretty obvious, and may affect your resale value.
However, you do want to make sure that you are measuring the actual countertop cutout, not the outer rim of the cooktop. You may need to squeeze into the cabinet and measure the cutout from below, or you may actually need to remove the old cooktop.
Once you have the actual size of the cutout, visit a large appliance store — not a home center — and have them research several different manufacturers for you to see if there is a top that will fit that opening. If not, see if there is one that is slightly larger, then talk with a tile contractor about cutting the opening larger. (If selecting a larger cooktop, make sure that you will still have sufficient clearance to the upper cabinets).
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