Hi-
I'm a new DIY-er with average plumbing experience. I am having hot water flow/pressure issues at one fixture (kitchen sink). Some notes below:
1) All plumbing is either copper or pex. Home was built in 1997, so relatively new plumbing. All the plumbing is in the basement ceiling and rises to the first floor to the fixtures.
2) The house is a ranch, not much lift required as a result, but the house is very long. The cold water has to go about 80 feet to the water heater and then about 80 feet back to the kitchen sink. It's quite a long run.
3) A year ago, a plumber installed a tankless domestic/hydronic combi heater (5.8 GPM Navien 240 (installed last year). Working great and no issues other than issue I'm discussing.
4) City water supply pressure and flow is good. I had it checked by the town, plenty of flow and about 50 psi pressure. City supply is 1 inch copper. I also checked pressure at hose bibs on either side of the house, both show 50 psi.
5) the 1" copper supply transitions to 3/4" copper which runs the length of the house. All fixtures are connected to this run through 1/2" copper off that 3/4" pipe. The 3/4" supply feeds right into the water heater and exits to another 3/4 inch pipe that also runs the length of the home.
I'm also attaching a link to a picture of the plumbing schematic for the kitchen sink fixture (not the whole plumbing system, just the parts with issues). From thick to thin, the lines represent 1", 3/4" and 1/2" pipe respectively.
The kitchen faucet is a single handle Moen (I believe, not positive the brand). Cold water pressure is no issue at the faucet, but hot water flow is significantly reduced and the sprayer doesn't spray when on full hot water (it trickles from sprayer). Probably due to the length of the run, it takes a good 3 minutes for the faucet to run hot. Hot water pressure is fine at all other fixtures (but all those fixtures are much closer to the water heater.
I've done the following:
1) Ensured all valves throughout the entire plumbing system are all the way open.
2) Ensured Navien flow restricter is the largest one (5.8 GPM) and is filter is clear.
3) Checked faucet aerator and the stops under the sink, to make sure stops fully open and no obstruction at the aerator.
My gut tells me that the reason I'm having problems has to do with the long run. I was thinking about taking out the supply hoses under the sink and running some water into a bucket to see if possibly an issue with the stoppers gunked up. Could possibly try to clean the faucet's check valve. Not sure if this is worth my time given fixture is new (installed two years ago) and the plumbing is relatively new too.
Any suggestions on how to proceed? If my issue is being caused by a long hot water run, is there anything I can do about that?
Thanks to all in advance.
-Rob
I'm a new DIY-er with average plumbing experience. I am having hot water flow/pressure issues at one fixture (kitchen sink). Some notes below:
1) All plumbing is either copper or pex. Home was built in 1997, so relatively new plumbing. All the plumbing is in the basement ceiling and rises to the first floor to the fixtures.
2) The house is a ranch, not much lift required as a result, but the house is very long. The cold water has to go about 80 feet to the water heater and then about 80 feet back to the kitchen sink. It's quite a long run.
3) A year ago, a plumber installed a tankless domestic/hydronic combi heater (5.8 GPM Navien 240 (installed last year). Working great and no issues other than issue I'm discussing.
4) City water supply pressure and flow is good. I had it checked by the town, plenty of flow and about 50 psi pressure. City supply is 1 inch copper. I also checked pressure at hose bibs on either side of the house, both show 50 psi.
5) the 1" copper supply transitions to 3/4" copper which runs the length of the house. All fixtures are connected to this run through 1/2" copper off that 3/4" pipe. The 3/4" supply feeds right into the water heater and exits to another 3/4 inch pipe that also runs the length of the home.
I'm also attaching a link to a picture of the plumbing schematic for the kitchen sink fixture (not the whole plumbing system, just the parts with issues). From thick to thin, the lines represent 1", 3/4" and 1/2" pipe respectively.
The kitchen faucet is a single handle Moen (I believe, not positive the brand). Cold water pressure is no issue at the faucet, but hot water flow is significantly reduced and the sprayer doesn't spray when on full hot water (it trickles from sprayer). Probably due to the length of the run, it takes a good 3 minutes for the faucet to run hot. Hot water pressure is fine at all other fixtures (but all those fixtures are much closer to the water heater.
I've done the following:
1) Ensured all valves throughout the entire plumbing system are all the way open.
2) Ensured Navien flow restricter is the largest one (5.8 GPM) and is filter is clear.
3) Checked faucet aerator and the stops under the sink, to make sure stops fully open and no obstruction at the aerator.
My gut tells me that the reason I'm having problems has to do with the long run. I was thinking about taking out the supply hoses under the sink and running some water into a bucket to see if possibly an issue with the stoppers gunked up. Could possibly try to clean the faucet's check valve. Not sure if this is worth my time given fixture is new (installed two years ago) and the plumbing is relatively new too.
Any suggestions on how to proceed? If my issue is being caused by a long hot water run, is there anything I can do about that?
Thanks to all in advance.
-Rob
Last edited:
