RESUMO:
Razões:
O código de construção pode exigir que você siga as instruções de instalação do fabricante. Relacionado a isso, ter um segundo loop embaixo da pia poderia ser mais fácil de inspecionar / verificar visualmente do que o embutido.
Aparentemente, dois loops são uma salvaguarda contra uma drenagem deficiente. Como tal, acho que você pode fugir sem tê-lo, mas parece ser uma prática recomendada ter dois.
PESQUISA:
Encontrei um artigo que discutiu esse problema específico e incluiu algumas informações do fabricante.
Pergunta feita aos fabricantes:
A high loop is required on the dishwasher drain in the installation
instructions for all of your dishwashers. What is the purpose of this?
Doesn’t the high loop that is incorporated in to the side of the
dishwasher achieve the same thing?
A IMO, a resposta mais clara, abordou os benefícios específicos de um segundo ciclo:
Viking: In testing our dishwashers, we have found that the additional high loop in the back of the dishwasher is required for
proper draining of the water. We have seen when this piece is not
applied that over time the consumer will have issues with the water
back up and causing issues with proper drainage and water pooling in a
particular area.
Outras respostas relatadas foram:
Kenmore: "The high loop or air gap must be used to prevent potential backflow contamination of the dishwasher. Local plumbing codes
generally dictate the requirements in your area. Section 807.4 of the
Uniform Plumbing Code states: "No domestic dishwashing machine shall
be directly connected to a drainage system or food waste disposer
without the use of an approved dishwasher airgap fitting on the
discharge side of the dishwashing machine. Listed airgaps shall be
installed with the flood level (FL) marking at or above the flood
level of the sink or drainboard, whichever is higher, or separately
trapped with the airbreak located on the stand pipe."
GE: "If an air gap is not required, the drain hose must have the high loop from the floor to prevent backflow of water into the
dishwasher or water siphoning out during operation."
Bosch: The high loop in the drain hose of your dishwasher is to keep water from settling in the hose if it were hanging down any lower or
horizontally. This keeps the drain hose dried out and keeps any odors
from backing up into the dishwasher.
Nenhum desses segundos grupos realmente abordou a questão específica de precisar de DOIS loops, mas eles explicam por que é necessário um loop, que ainda é um contexto útil.
