4 hp grundfos pump for a lawn sprinkler system. It is set-up so that it only boosts psi to the irrigation system and not the house. When it runs however, air gets into the house side and spurts out of the upstairs spigots. How do I get rid of the air problem? It ran fine when we shut the system down for the winter but started when we turned the irrigation system on for the Spring
Garden - Grundfos - MQ3-35 3/4 HP Pressure Booster Pump
Answers & Comments
With the pump operating, run any and all faucets for as long as it takes to get all the air out of the lines, (or as long as the pump is programmed to run).
Run all faucets at the same time so the air is pushed out from multiple places.
The pressure at the faucets should regain fully once all the air is released.
Please let me know if you need furhter assistance.
carsandcomps,
Guru, Premium Expert @ Fixya.com
NOTE: make sure none of the water lines under the house or any linked to the sprinkler system have been damaged from cold weather.
So if the faucets inside the house are only having air come out when you first turn them on, the valves inside may be worn. You mentioned it only does this in the upstairs faucets? How many do you have upstairs? I would check the water lines under the house (basement), as well as your hot water heater.
Let me know if you need further assistance.
carsandcomps,
Guru, Premium Expert @ Fixya.com
Okay, after my more recent post, I read your comment again - you stated that the house runs fine until the next cycle - somehow the pump is drawing the water back down from the house when it's turned on - causing air to be drawn in from the faucets. Because of gravity as well, this is only affecting the upstairs ones, because the water is keeping the lower lines full as the water is drawn downward.
Does the sprinkler system work okay? Does it seem weak, or does it maintain steady pressure?
carsandcomps,
Guru, Premium Expert @ Fixya.com