JayEss
New Member
Hi everyone,
I'm planning to add a recirculating pump on my hot water line, as it takes about a minute for the fixtures furthest away from the water heater to get hot water. I have a thermostatic mixing valve which I know makes things a little more complicated, but from my understanding it's still possible to add a recirculating pump as long as it's temperature-controlled so it doesn't run constantly. Some info about my home:
And here's how I'm planning to change it:
So now, onto my questions:
I'm planning to add a recirculating pump on my hot water line, as it takes about a minute for the fixtures furthest away from the water heater to get hot water. I have a thermostatic mixing valve which I know makes things a little more complicated, but from my understanding it's still possible to add a recirculating pump as long as it's temperature-controlled so it doesn't run constantly. Some info about my home:
- I have a dedicated return line for recirculation.
- I have a Braukmann AMX300LF mixing valve, which has a dedicated inlet for recirculation.
And here's how I'm planning to change it:
So now, onto my questions:
- Does this look right, or does anything need to be changed here?
- Should I be removing the check valve that's between the water heater and the mixing valve? All of the installation diagrams I've seen don't have a check valve there.
- My house is plumbed with PEX and the dedicated return line has a 1/2" copper stub-out. What's the "right" way to hook up the pump to that stub-out? From my understanding I don't want to sweat the copper stub-out since the heat can damage the PEX in the wall, so I was thinking I could use a compression x FIP fitting and an MIP x PEX barb and then just run PEX for the whole thing.
- I'm looking at a Grundfos 99412493 pump, which has a built-in temperature sensor so no aquastat is needed. According to Grundfos this pump runs for 10 minutes to determine the max temperature of the system, then automatically turns the pump on and off to keep the water temp 7-14 degrees Celsius lower than the max temperature that it previously detected. That 10-minute run to find the max temp repeats every 12 hours. Will that work correctly with a mixing valve, or would it be better to go with a more traditional system that uses an aquastat?