Dishwashers - Chemical and Hot Water - Is there a difference?
Oct 31st 2013
So what is the difference between a chemical and hot water sanitizing dish washers? Ultimately, both methods will get your dishes clean and adhere to safety and health requirements, but they achieve the results in two totally different manners.
One key function of any dishwasher is to sanitize the dishes. In a low temp system, the dishes are washed with 120°F water which is generally water coming right out of your boiler. Once the dishes are washed, a chemical sanitizing solution is rinsed over the dishes to neutralize any bacteria that may remain. The high temp machines have a hot water booster that increases the incoming water temperature so that your dishes are washed at 160°F and then rinsed at 180°F. The hotter temperatures sanitize the dishes.
Both systems have pros and cons, so making the right decision will depend on your situation. In short though, low temp systems do not require a costly booster, or require special electrical services. This will make them less expensive to both manufacturer and install. Conversely, you are then committed to purchasing chemicals for the life of the dishwasher, causing the overall lifetime cost of the dishwasher to far exceed the hot water. Low temp machines are not recommended for stemware or glassware. The lower temperatures can leave spot marks, streaks, or even lipstick stains.
| Low Temp Sanitizing (120°F wash, Chemical solution rinse) | |
| PROS | CONS |
| Uses standard 115 v electrical service | Requires chemical sanitizer for rinse cycle |
| Less expensive to manufacture and purchase (no booster heater) | Not recommended for stemware |
| Installation can be less expensive (no need to upgrade electric service or existing water heater) | Potentially higher reject rate (and labor costs) due to difficulty with proteins, fats and lipstick |
| Can be purchased or leased from chemical companies in most markets | Corrosive sanitizer can limit service life of machine |
| Dishes come out cooler to the touch | Dishes come out wet |
| High Temp Sanitizing (160°F wash, 180°F rinse) | |
| PROS | CONS |
| Unlimited applications | Requires booster water heater |
| Hot water cuts through grease, proteins, lipstick | Requires larger electrical service |
| Machine lasts longer without caustic sanitizer | Typically more expensive to manufacture and purchase due to booster heater |
| Lower chemical costs | Installation can be more expensive if electrical upgrades or a new hot water heater are needed |
| Less spotting |
|
There are situations where low temp machines are required such as older buildings or existing kitchens where a new higher voltage line cannot be run. In general though, you need to look at your specific application, total daily usage, budget, and location to make the decision on which machine to purchase. Globe is happy to help research options, whether your set-up needs are small or large. We have the resources to quote varying options from leading manufacturers of commercial ware washing equipment.