Water heaters

[Howard]

I'm looking to replace an old boiler possibly with Paloma units. Anyone have experience with these or know how to determine what size and how many to install?

Thanks

[Jeff Deal]

Dear Howard:

The biggest difference in switching to that style of water heater is that you will have no storage for your peak times. The maximum flow through each of the Paloma's is just less than 5 gallons per minute (if you want any hot water at all coming out). The decision you have to make is how many washers you want to be able to fill at one time on a hot or warm setting. Most machines with a capacity of less than 75 lbs including toploaders have a fill rate of 4 gallons per minute. A typical peak day throught the industry would have 35 - 50% of the machines looking to fill at the same time.

[PeterH]

Yeah, but I know that they install more than one at a time and they run somehow in tandem with eachother to supply enough hot water. A fairly large laundry opened in the ATL area with them, and they have at least 6 of them hanging on the wall to supply all 36 machines. You'd have to contact them or their distributor directly to see how they figure out how many heaters are needed.

-ph

[Jeff Deal]

A little quick math tells you that they have the capacity of 30 gallons per minute so they can fill 7 - 8 machines at once. If that is the maximum demand of their laundry, it's sized correctly. If no more than 23% of the users of that laundry will need to fill on a hot or warm setting at the same time, it works. If more than that percentage of machines are on a hot or warm setting and more than that percentage happen to be filling at the same time the fill time will increase as the flow gets spread between more machines. The net effect is less turns per day per machine used on these settingss.