water pump pulsing

[FionaGrant]

On our latest weekend out, the city water pressure was too low so we filled the fresh tank. Might have overfilled it, in fact as we didn't notice when it started overflowing.

But the strange thing was, depending on the tap we used, the water pump would either run continuously, or pulse on and off.

The other issue was that the pump would come on just for a fraction of a second every once and a while with no water running. I'm guess this is a slow leak of pressure? But I cannot see from where.

Thanks,
Grant and Fiona

[Grumpy]

The pulsing will depend on how much water the faucet is allowing to flow so yes you will see a difference. As to the periodic operation, the back flow check valve in the pump may be allowing the pressure to drop so you may not see the leak since it is internal. Could be a small piece of debris stuck, doern't take much.

[Zenar]

I had a small leak once and the pump would run once every couple hours. it wasn't much but it was there. I ended up stepping beside the shower and the water came out in the night. It was the water running down the tap on the sink and puddling under the shower.
My trailer wasn't quiet level so this time it came out.
As for the pump running off and on, it depends how much water you are letting out. If your system has air trapped in it, the pump will build pressure and hold it longer due to the air compressing and maintaining that pressure. I think my hot water tank had water trapped in it. When I ran my cold water it would get spurts of hot water, which i think was coming back out from the hot water tank causing this effect. Sorry for the stories about my own issues i came across lol

[Shokyle1]

My pump kicks on in the evening for a second usually at night when the water heater has been shut off for a while and the water starts to cool down and drops pressure in the lines.

[Bullitt6283]

When I had a TT the water pump would 'grunt' about once an hour. We had to shut it off before retiring at night, since the pump was under the bed. I found out that it was actually a leak in the plumbing, and there was water damage.

[RichR]

You may want to tweak the pressure switch a bit. Looking at the wire connection end of the pump there is a setscrew to the left of the wire that takes a small hex key wrench. Turn it a wee bit at a time until the periodic pulsing stops. It should only need a fraction of a turn.

[FionaGrant]

Thanks to everyone for the great advice!