Hot Water Recirculation Problem

Earlier when I had trouble with the hot water circulation pump breaking the boiler flow control, I decided to install a pressure regulator/reducer between the pump and the cold water input for the hot water side of the boiler and for this function I used a 1/2″ threaded Watts EB45 with settings between 10 and 70 psi. It ships at 45 psi. Although the boiler doesn’t specify the maximum psi input, I assumed that 45, which is a common household water pressure, would work fine. I also installed the pump a few feet above the incoming line–an idea I got from some online source–and installed a shutoff below it as recommended for maintenance and change out.

Taco 009 Stainless Pump

Taco 006 Stainless Pump (dark blue) Installed–Watts pressure reducer just visible on the left of the red tank.

At some point after the fix, the hot water recirculation was not working. I’m not sure when it quit but when I noticed we were not getting hot water after turning the pump on for a few minutes, I just unplugged the recirc pump.  So we were washing our hands in cold water and collecting the 5 gallons of shower water that it took to feel hot water coming out of the faucet in a bucket and taking it out to the garden. Finally I had some time to troubleshoot the system.

At first I thought the pressure regulator was not high enough for the boiler to recognize the flow. But setting the pressure higher did not get the water heater to come on when the pump was on. I adjusted it back down, but now I have no idea now how low or high it is set!

Second, I thought it must be the pump. I had trouble with another ebay pump that I ordered so I thought it might just be a bad purchase and I looked for another recirculating pump that I could use instead. I settled on this Laing hot water pump, it has the energy saving ECM technology (Electronically Commutated Motor) and the E3 is the larger of the two models, able to pump more than 75′ of water circulation piping. It also has a variable speed setting to manually set it for the system that is using it. But a temperature sensor would have to be installed separately.

Laing E3 Pump

Laing E3 Pump

As I started to install the new pump, I noticed that the ball valve that isolated the pump for maintenance had been left OFF! So no wonder the pump was not starting the hot water boiler, it wasn’t the pump that was not delivering water, there was no water getting to the pump! I was lucky that the times that it was pumping without water flow did not wear out the pump. It actually worked fine when the valve was reopened. As there is a temp control on the pump, when the water reaches the preset temperature, the pump shuts itself off when plugged in directly, but there had to be another way to turn on the pump to initiate hot water.

The Taco D’Mand system had a wireless remote system to turn the pump on so I decided to replace the timer with a remote control system. I needed something that would work from the furthest bathroom so a simple lamp system didn’t seem powerful enough. I settled on the Skylink system and as an added benefit, the receiver (PA-318) allows for setting a time limit for the on signal.

Both the receiver and remote (TC-318-1) were reasonably priced on Amazon and the operating distance is rated at 500 ft. This system is working great. I set the timer for 15 minutes but the water gets hot about 5 minutes after pressing the remote, an easy wait to start taking a shower with no water waste. Since the pump shuts off when it reaches the design temperature, and on again when it gets cooler, we can just let it run for those 15 minutes until we are ready to shower.

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