# Minimum  Flow  Rates



## globe trekker (Jul 22, 2013)

Greetings to you all!

I am looking for information on the minimum flow rates for a restaurant hot water needs.

In looking at Table 604.3 in the 2006 Edition of the IPC, I see rates for lavatories, but

nothing on a 3 compartment sink. This particular project wants to convert from a tank

storage type of water heater to an instantaneous type. The project will have 2 - lavatories,

1 - hand wash sink, 1 - 3 comp. sink and 1 Service Sink. No flow rates are required for

the Service Sink per Section 604.4, Exception # 4.

Does anyone have a code reference or standard that I can apply?

Thank you!

.


----------



## Mech (Jul 22, 2013)

Try contacting the manufacturer.  They should have sizing info available.


----------



## Gregg Harris (Jul 22, 2013)

globe trekker said:
			
		

> Greetings to you all!I am looking for information on the minimum flow rates for a restaurant hot water needs.
> 
> In looking at Table 604.3 in the 2006 Edition of the IPC, I see rates for lavatories, but
> 
> ...


604.4 should also apply to a three compartment sink, they can be used in large volume filling of the sink, pans, kettles etc. maximum volume should be looked at and the health department  requirements for volume.


----------



## globe trekker (Jul 23, 2013)

Thanks "Mech" & "Gregg H." for the input!

If I may, I will ask the question a different way.   I want to purchase a natural gas water heater

for a Commercial restaurant, and I have a Hand Wash Sink, a 3 Comp. Sink, 2 lavs., a Service

(Mop) Sink, and maybe a Commercial dishwasher that will be installed.

I am using the 2006 Edition of the IPC. If I use Table 604.3, what flow rate (in gals. per min.)

do I use to size this (hypothetical) water heater, for all of these plumbing fixtures & the

dishwasher, or are there other code sections that I should refer to?

Thanks!

.


----------



## Gregg Harris (Jul 23, 2013)

globe trekker said:
			
		

> Thanks "Mech" & "Gregg H." for the input!If I may, I will ask the question a different way.   I want to purchase a natural gas water heater
> 
> for a Commercial restaurant, and I have a Hand Wash Sink, a 3 Comp. Sink, 2 lavs., a Service
> 
> ...


  Check with you local health department, this is usually where the design criteria requirements begin. A tank-less system for a restaurant needs to take into consideration assuring that there is enough hot water to meet health department standards and will be based on the type of restaurant, occupancy load. etc. There is no cut and dry method for determining other than making sure there is plenty. If the dishwasher is running and pots and pans are being rinsed and water demand for the cooking process are happening at the same time can have a large demand factor on the system.


----------



## globe trekker (Jul 23, 2013)

Thank you "Gregg H." for your rply!

Unfortunately, in this jurisdiction the Health Dept. isn't much help.

*To all:*

IMO, there should be more fixtures and flow rates in Table 604.3 of the IPC, ..another

code section, or another referenced standard.  Table 604.3 seems to be incomplete!

What do you other code officials do in determining (minimum) flow rates?

Thanks!

.


----------



## Mech (Jul 23, 2013)

For supply piping, I would think a three basin sink could be modeled using a kitchen sink multiplied by the number of faucets.  For sanitary, I think you count it as three sinks (unplug all the basins at the same time.)


----------



## Gregg Harris (Jul 23, 2013)

globe trekker said:
			
		

> Thank you "Gregg H." for your rply!Unfortunately, in this jurisdiction the Health Dept. isn't much help.
> 
> *To all:*
> 
> ...


 Here is what I would be concerned with in an restaurant scenario. I would focus on the maximum demand factor of the appliances that required hot water, dishwasher, steam unit, sterilizers etc. and your three compartment sinks for large pots and pans and hand washing both in the kitchen and bathrooms. You do not want to run out of hot water when the product you are providing and the number of patrons being served is dependent upon it.


----------



## Mech (Jul 23, 2013)

Globe Trekker: Are you designing the system or reviewing the design?

I do not know of any ICC regulations for hot water other than pressure, flow rate, and maximum temperature.  The codes do not address the duration of hot water supply, at least not which that I am aware.

If you are designing the system, there are some questions you will need answered.

Is this a deli where water usage is low or a dine-in restaurant with a high volume of dishes being washed?  Can the owner / manager tell you how often and how long the kitchen equipment is drawing hot water?

How much water does the dishwasher use per cycle?  How hot of water does it need?  The manufacturer should have specs for this.  Is a water heater booster used to reach 180 degrees?

Installation of several smaller instantaneous heaters may be helpful, albeit more costly, to ensure sufficient hot water is available.  I am not very familiar with the instantaneous heaters.  Is there a model available to supply a single lav and then also simultaneous high demand fixtures?

If the mop sink is typically only used at the end of day, perhaps that piece of equipment is not factored in to the sizing calculation.

Hope this helps somehow.


----------

