Application
Commercial food service operations must use one of two approved methods to sanitize dishes in the dish washing process: water temps above 180F or chemical (chlorine) additives.
There are pros and cons of both methods, but for those who choose the hot water method, most use electric booster heaters to get up to 180F. Standard natural gas water heaters are not designed for that high of temperature, so they either cannot get that hot, or are very inefficient at those temperatures. It is also not safe (or legal in many cases) to have water that hot be distributed to the entire facility for other use, such as hand washing.
Typically a gas water heater will be used to get the water to about 140F and then boosted electrically. Even a small electric booster heater can be 30kW, which substantially increases cost, especially if on a high demand charge tariff. (Large operations could use commercial boilers, but this is rare in average restaurants.)
Sample Operating Cost Comparison
ASSUMPTIONS:
130 gal per hour x 6 hours = 520 gal/day (large, busy restaurant)
Natural Gas Cost $1.15/CCF
Electricity $0.12/kWh and $8.00 per kW Demand Charge
Gas
520 gal x 8.3 lbs x 140F rise = 604,240 BTUs (if 80% eff = 7.5 CCF)
7.5 CCF x $1.15 = $8.62 per day
Electric
604,240 BTUs / 3,413 = 177 kWh / 6hrs = 29.5 kW
177 kWh x $0.12 = $21.24 per day
PLUS 29.5 x $8.00/kW demand = $236 per MONTH
If just Electric Booster and natural gas base load heating:
29.5kW x $8.00/kW Demand Charge = $236/month/20 days = $11.80/day in Demand PLUS ~50 kWh x $0.12 = $6.00 per day (if 40F rise)
Manufacturers
Raypak
The B-195 Gas-Fired Booster Heater dependably maintains an ample supply of 180°F water for warewashing sanitary rinse requirements. It’s copper finned tube heat exchanger and solid state electronic temperature control give the booster a near instantaneous response time and a temperature control band of ± 2°F. Raypak also has units with 50,000 and 130,000 BTU input.
Designed to work with most flight type dishwashers, the B-195 provides a cost effective alternative to electric booster heaters. The unit conveniently fits underneath standard kitchen counters and can be installed without major alterations to the existing kitchen layout.
See installation manual for special venting requirements.
©RAYPAK, INC.
31111 Agoura Road
Westlake Village, CA 91361-4699
Telephone: 818-889-1500
Fax: 818-889-4522
RAYPAK CANADA LIMITED
2805 Slough St.
Mississauga, Ontario Canada L4T 1G2
Telephone: 905-677-7999
Fax: 905-677-8036
Hatco
Hatco offers 3 models, PMG-60, PMG-100 and PMG-200, which also identifies their gas inputs (ie: PMG-60 = 60,000 BTUs).
Hatco Corporation
P.O. Box 340500
Milwaukee, WI 53234-0500 USA
Telephone: 800-558-0607, 414-671-6350
Fax: 800-543-7521
Web site includes product literature and a savings calculator to compare gas versus electric booster heaters according to a number of variables.
PrecisionTemp
Not only do you get your dishwares cleaner, you reduce your operating costs. In most kitchens you will save over $400 monthly compared to electric boosters.
And the PrecisionTemp Model 56 is ventless!
This high efficiency gas booster heater is ventless because it uses our patented Variflame Control. It performs 80% more efficiently than the allowable code. This means lower operating cost and easier installation where space is usually at a premium.
Even if you are using a low temperature chemical washing system our gas booster heater may still cost no more. And, you would have the many benefits of a high temperature system for as little as 1 cent per cycle!
Using the Variflame Control. your primary water temperature is checked over one hundred times each minute. Then, Variflame uses the precise amount of energy needed to deliver a 180º rinse. No more, no less. The Model 200 delivers 180º rinse water with as little as 110º primary water.
The Model 56 is reliable and designed for easy serviceability. The standard stainless steel case provides easy access and all components can be reached from the front of the booster when service is required.
PrecisionTemp
1006 Kieley Place
Cincinnati, OH 45217
Telephone: 513-641-4446
Fax: 513-641-0733
Source: Text Bob Fegan 8/01, 4/02; Manf web sites listed above 4/02; 3-10-03; rev 11-2004; rev 2/2007;