Hot Tip #24 – Stain Gauge

How does the strain gauge on my tunnel loading conveyor work? The strain gauge is one of the most widely used strain measurement sensors. It is a resistive elastic unit whose change in resistance is a function of applied strain. Where R is the resistance, e is the strain, and S is the strain sensitivity […]

Hot Tip #23 – Salt Usage

Are you using too much salt when you regenerate your softeners? Most laundries are. A simple check: Salt usage should be between:      3.1 to 3.6 grains of salt used per grains of hardness removed.    I round it off to between 3 & 4 grains per grain. Another way to state that is, that one pound […]

Hot Tip #22 – Boiler Blowdown Exchanger

Boiler blow-down occurs from two different boiler locations. The first location is from the bottom of the boiler water reservoir. This is known as “bottom blow-down” or “rapid blow-down”. It is usually less than 10 seconds in duration and depending on water quality is performed once or twice per shift. This blow-down is intended to […]

Hot Tip #21 – Refrigerant Type Compressed Air Dryers

Question: I have a refrigerant air dryer after my compressor. The temperature of the exit air is only “slightly” colder than the inlet air, and yet the dryer seems to be working fine. How is this possible? Within the compressed air dryer, there are two heat exchangers. Exchanger # 1 is a compressed air to […]

Hot Tip #20 – Ozone

Instead of adding ozone, it is much cheaper & safer to use a low-pressure high-volume blower to blow atmospheric air into your wash water. The addition of this air seems to have all of the same benefits as the ozone. I do not know if the benefits are due to: The oxygen & ozone that […]

Hot Tip #19 – Flash Steam

The percentage of flash steam (by weight) that will be formed when discharging hot condensate to a lower pressure is easily determined by using this formula. The sensible heat (heat of the saturated liquid) of the condensate at the lower pressure is subtracted from the sensible heat at the higher pressure. This number is then […]

Hot Tip #18 – One More Degree

Frequently when I’m talking to laundry operators or their engineers, I ask them what it would be worth to them if they could recover one more degree with their wastewater heat recovery system. The most common response is “Gee, I don’t know”. When encouraged to make a guess, their response is something like “I bet […]

Hot Tip #17 – Ironer Folder Drops

Ironer Folder Drops

Hot Tip #16 – Air Leaks

While visiting laundries one issue frequently arises, how to handle compressed air leaks. Most leaks that I find are very difficult to correct. The easy ones are generally corrected by facility maintenance long before I arrive. The easy ones are those that you find in the air delivery plumbing. Examples include:  leaking quick disconnects, a […]

Hot Tip #15 – Condensate Return Lines

All condensate lines should be pitched down 1/4″ per 10 feet (5 mm/m) to allow for drainage of the condensate by gravity. The most efficient return systems are, by design, not completely full of liquid and are not vented to the atmosphere. They are referred to as dry-closed systems. They handle condensate at steam temperature […]