A hot water recirculation pump provides a number of benefits for any household, especially in times of limited water supply. These pumps provide instant hot water, reducing the waste caused by letting water run until it comes hot from the tap. Millions of gallons of water are squandered every year because of this.
A recirculation system is a hot water line that runs throughout the house and returns back to the water heater. It has a timer that turns on the pump at regular intervals, mostly during peak usage times. Here are four problems with these pump systems that you should be aware of.
1. Power Waste
Because the pump is continually heating and circulating hot water through the pipes, it can use a lot of electricity. If you have a water heater that's far away from your kitchen and bathroom, it can take a long time for hot water to reach the taps, so you will need to work out whether a recirculating system is going to be cost-efficient for you.
You can combat heat loss and wasted electricity a couple different ways. All supply and return pipes should be well-insulated to prevent as much heat loss as possible. Making sure the pump is turned off late at night can help with some of the power waste as well; even systems that use a temperature sensing unit to shut off the pump when the water reaches a certain temperature don't help with the power usage if the water is losing too much heat too quickly.
On-demand pumps are a better alternative if you are worried about power waste.
Recirculation pumps are vulnerable to flow-accelerated corrosion, which can be a costly problem. This corrosion is caused by excessive flow velocity or aggressive water chemistry, and the pipes end up being eroded away by the water inside. The most frequent affected areas are bends, elbows, and tees where the walls of the pipe become so thin that they eventually rupture. The only fix for this problem is to change to a lower capacity pump and reduce abrupt changes in pipe directions.
3. Noise Problems
Noise problems that happen after a power outage can be caused by air entering the system. To fix the issue, you will need to 'bleed' the system to allow the air to escape. Open the small air escape valve until water comes out and then repeat on all other valves.
4. Low Flow Rate
Hot water recirculation pumps sometimes have a very small motor, which means that they can't produce much head pressure. This can negatively impact the flow rate. Many of these pumps can't even turn on a tankless heater.
As long as you can compensate for or repair any problems caused be a recirculating hot water system, then it can be a convenient and water-saving feature for any home. Before you think about having one installed, consider these issues and concerns and do the research to see if this system is right for you.