Learn about using a bilge pump or a high-flow pump.
Brush up on pump requirements here.
Typically, a bilge pump or another high-flow pump is used to supply water to an off-grid property. This is a wonderful water system that can supply many appliances on the property, including sinks, showers, washing machines and a bit of a sprinkle for the "Betty", the sheepdog.
When trying to connect a HOTTAP into the mix, we can run into some issues.
Firstly, the best thing to do is to grab a suitable 12V pump to use with your HOTTAP, so that it has a dedicated water supply. You can check out pump specifications here. You can look at our Off-Grid Plumbing (12V pump kit), or consider grabbing a HOTTAP model that already has a pump. Check out the HOTTAP models here (look at the Essentials and Nomad).
Here are some issues you may run into when using a bilge pump or high-flow pump:
- Water flow is too high and messes with the HOTTAP
The HOTTAP has a water flow regulator that limits any input water supply above 6 litres/min down, to a maximum of 6 litres/min.
So, if you use a very high flow pump, for example, a bilge pump with 40+ litres/min of flow, then you can imagine the disruption that occurs when HOTTAP tries to limit 40 litres/min down to 6 litres/min.
It's like packing 5 people into a single-lane swimming pool and telling them to swim side-by-side. It's difficult to imagine that anyone would actually be swimming.
And this "disruption" of flow, at the HOTTAP, results in a huge drop in water pressure. This can drop the pressure below the minimum requirement of 10 PSI, causing the HOTTAP to turn off.
- Running too many appliances at one time
This is another way that we lose water pressure. You can imagine that each appliance will take a portion of the (limited) water pressure from the high-flow pump.
So, if you are just using the HOTTAP, then the system could work fine. And, as soon as you turn on another sink, put a load of washing in, or Betty decides to do some "mud sprints", the water pressure would be sent to multiple appliances, and potentially not enough would be sent to the HOTTAP. Causing it to turn off.