Part 2: Specifying a Hot Water System for a Snack Food Manufacturer

Last week, we talked about the Hot Water System for a Snack Food Manufacturer. Here’s the 2nd part of our blog specifying WaiWela tankless water heaters.

Due to space limitations inside the Snak King manufacturing plant, Ponce proposed mounting the 28 WaiWela tankless water heaters on two skids in different locations on the roof of the plant. Two galvanized steel skids were fabricated at grade by Coast Aerospace in Huntington Beach, CA. One skid has 16 PH28-COF units plumbed in parallel with a 1/8 HP circulator pump to deliver immediate hot water to one area. The second skid has 12 PH28-COF tankless units plumbed in parallel with a 1/8 HP circulator pump to deliver immediate hot water to another area at the plant. Both skids are mounted on the roof of the Snak King manufacturing facility. The lightweight design of this system allowed for installation without increasing the load bearing of the roof.

tankless water heater unitThe WaiWela by Paloma tankless water heater has an energy factor of 0.82. The tankless heaters are particularly energy efficient in this application because they modulate continuously to produce only the amount of additional heat needed by current demand in the system. These high-efficiency units also qualified for rebates from the local gas company and federal tax credits.

Each WaiWela tankless water heater bank is controlled by a MIC-180 multi-unit system controller, also produced by Paloma. The MIC-180 multi-unit system controller controls and modulates the firing of each WaiWela heater in the system, and rotates the sequence of firing to evenly distribute use of all units over the lifetime of the system.

The WaiWela water heaters were plumbed in parallel to provide redundancy and each was installed with an isolation valve kit to allow for individual servicing. The isolation valve kit by Webstone will allow for servicing each unit by itself without disrupting hot water service to Snak King’s manufacturing plant below. Tru-Flex Metal Hose Corp.’s Home-Flex high volume gas connectors were installed to allow for the high BTU/hr. volume required for a tankless water heater. This allowed the installing mechanical engineer to eliminate having to use rigid gas pipe to each tankless unit. Falcon Stainless Steel water connectors were also installed to eliminate plumbing rigid copper pipe from the 4-in. manifolds to each WaiWela tankless water heater.

Another advantage of this system was to allow for future expandability. The skid that has 12 WaiWela tankless water heaters is set-up to be expanded to 16 units for increased future manufacturing capacity at the Snak King.

Finally, the cost of each commercial tankless system was significantly less than a comparable boiler system. Each WaiWela tankless water heater, with input below 200,000 BTU/hr., did not require the ASME approval that can effectively raise the cost of larger systems.