Right now, the hot water coming out of my kitchen faucet is very very low-flow. Just a bit above a trickle.
But just an hour or so ago, the flow was fine. Just as it will likely be the next time I try it.
This intermittent low-flow problem only exists for the kitchen sink. Only for the hot water. And it’s been going on for some time now, like the last couple of months. I don’t know what could be going on. Before anyone asks, no one is using the hot water but me, and the only thing I’m trying to do is fill my sink with hot water. I’m not using the washing machine or dishwater. I have a dual water heater/forced air furnace. I know the water heater has to be involved in some way, but I don’t know what that way could be.
I’m no plumbing expert, but you might have sediment that’s clogging up your water heater. Last year my hot water started becoming cloudy and brown and that was the problem. See here.
Because whatever the problem is is expanding when the hot water heats it up, then contracting after it cools off.
Does it work at first then slow down after the hot water’s been running through it? If it’s a single handle faucet you could try running just cold water through it for a minute or so and then try the hot water again and see if that temporarily fixes the problem.
If you own the house, you can do some investigation to see what’s going on. First, check the aerator on the kitchen faucet. The aerator is the little part on the end of the faucet. Unscrew it with some pliers and turn the water on (cover the pliers with tape so you don’t scratch it). If the water flows freely, then likely the aerator is clogged, although I would expect both the hot and cold to be impeded in that case.
With the aerator off, turn the hot water on and off full blast. With the aerator off, the water will flow faster and if there’s something in the line, it may be able to clear it.
Go under the sink and turn off the valves. Open the faucet to release the pressure. With the faucet open, go under the sink and open the valves. The sudden pressure may be able to clear the obstruction.
The reason why it may happen intermittently is that there may be a bit of calcium or something that is in the line. Depending on how it’s aligned, it may block more or less of the line. Hopefully by changing the pressure drastically you’ll be able to clear whatever is in there.
It’s in your kitchen sink faucet assembly. Disassemble the valve, clean it out, replace the valve cartridge if it seems fubar’ed, and as a last resort replace the whole thing with a modern unit.
If you have cast iron lines then it’s possible a piece of sediment is in the line. Otherwise it’s likely a piece of sediment in the faucet mechanism. Cast iron line will corrode and look like this. Copper can look like this. What I pulled out of my 80 year old house looked worse. It’s possible a piece of corrosion has broken loose and when things heat up it wedges.
Nitpick: that is galvanized steel pipe not cast iron. To the best of my knowledge cast iron is never used for fresh water lines. It is used on waste lines.
I guess I’ve got to call the super because it’s doing it again. One moment it’s high flow, and then the next it’s low flow, like a trickle. I feel like someone’s playing a stupid prank on me.
It almost certainly has some junk in the passages of the valve cartridge. They can be complicated little bits of engineering, with a whole stack of disc valves and ports, and a loose bit of plastic, corrosion, calcification, anything rattling around will cause strange behavior.
What you or the super need to do is the above: take it apart, clean out the valve cartridge, and replace it if it’s badly sedimented or damaged.
The hot water/furnace arrangement might be why the problem is intermittent. I’m not all that familiar with these newer forced air systems, but on the old hot water heating systems with baseboard heaters you can sometimes definitely get noticeably reduced hot water pressure when the system is circulating. It could be that you do have some partial blockage in the faucet, but there’s only enough water pressure to overcome it when hot water isn’t circulating through the forced air handler.
Try this… When the water is low-flow from the kitchen sink, leave the faucet open so it keeps flowing. Try every other hot-water faucet in the house. Do any of them have low flow at the same time?
This seems like the most valid hypothesis. I don’t possess the tools to open up my faucet (and haven’t had a chance to call the super), so maybe there is crud flummoxing everything. But it seems to me that if there was just sediment blockage, it would be consistent low-flow. Not this on-again, off-again craziness.
Also, you know how when you turn on the hot water tap after a hiatus, a good 30 seconds or so worth of cold water comes out first? Seems to me that if there was blockage in the cartridge, this cold water would also be low flow. Sometimes it is. But sometimes it’s high-flow, and then right when the water temperature gets hot, that’s when I only get a trickle. (It occurs to me this is critical information I should have shared earlier. Doh. :))
My observation skills leave a lot to be desired, so I’m not 100% sure I didn’t have this problem this summer. But I know it wasn’t a big annoyance until about two months ago. Corresponding to the length of time my furnace has been in full swing.
Just like the proverbial singing frog, of course it’s not doing it now. But the next time it does, I’ll make sure to remember to check the bathroom. I haven’t had any problems getting hot water while I take a shower, but it could be that I’ve just been very lucky.
