Fresh water tank and pump

[CharlieSK]

Two topics that may or may not be related.

First, last year (our first with the Airstream) it took a long time 20+ minutes to fill our fresh water tank. This year, the tank seems to fill much faster, even after completely emptying the tank. Capacity is listed at 54 gallons. When we return home, I will fill and then empty and measure.

Second, over the past week, the water pump does not sound like it is running smoothly and the water flow out of the faucets varies at about the same frequency as the pump sound. First thought it was because the fresh water tank was low, but refilled in our driveway and it did not seem to make any difference. Will tackle this next week as well.

Thank you in advance for ideas or solutions.

[Rich W]

How long it takes to fill your fresh water tank would depend on the water pressure and hose size at your house, or wherever you're filling it from, hopefully with a lead-free hose.

Your water pump is 12 VDC and other things could be affecting its performance. Are the water taps spitting air, you might have air in the lines and the pump can't reach the right pressure.

What do you mean "not smoothly"? Is the pump speed varying up and down? The pump will stop when the correct pressure is reached and the tap is closed. When you first turn on the tap the pressure is higher than what the pump can maintain, or it would shut off. It should initially drop a little than do a steady pump.

Have you checked the aerator screen? These get clogged from the sediment in the hot water tank and can affect performance.

Is the hot water heater bypass valve fully open?

Is the fluctuation for hot and cold or just one of them?

[CharlieSK]

1. My plan is to fill the tank and then drain and measure.
2. The pump sound does not occur when flushing the toilet, using the shower or when both hot and cold are on in the bathroom sink. Occurs when using the kitchen faucet (lever for hot and cold) or just hot or cold in the bathroom sink. We had issues with sediment this spring after we de-winterized. I plan to investigate further this PM in the driveway. May be sediment in the intake, pump or something else.

[AnnArborBob]

You may have air in the supply line to the faucets that are causing you problems. Try opening those affected faucets (one at a time) and running the pump for an extended period of time (five minutes or so.) You might have to open and close the faucet quickly a few times to get the air pocket out of the line.

[CharlieSK]

Thank you for the ideas and input.

After trying some of the ideas listed, we were down to the pump only running poorly when the bathroom sink was running hot - with the aerator attached. (I had soaked the aerator in vinegar and then disassembled and cleaned). To make sure the fresh water tank did not have a capacity issue, I filled and then emptied through the bathroom hot water side into a 5 gallon bucket - total volume was 47.5 gallons - close enough to the 54 considering there is probably still some in the tank. Now the pump sounds fine all the time, so there must have been some air in the lines. I also checked the filter on the vacuum side of the pump and it was clean.

Making progress and should have stopped there.

Since the system monitor has never read the fresh water, I decided to calibrate since the fresh water tank was empty. I added some water and then started into the calibration process for one tank. The sensor for the fresh water tank is not working and the system is now stuck in calibration mode. Looks like I will have to recalibrate all the tanks now - new sensor is ordered.