That is not a RO booster pump, you have the wrong one. That is a container pump. The
booster pump is the Aquatec CDP-8800 Booster Pump or 6800

Aquatec DDP-5800 Delivery Booster Pump (YOURS)

The DDP-5800 pumps can draw water from a ***holding tank and pressurize it***, or boost
the pressure from a low pressure source.


Aquatec CDP-8800 Booster Pump( WHAT YOU NEED)

For RO Systems*** Over 50 GPM ***- CDP-8800 Series High Flow). The CDP-8800 Series pumps
are also compatible with most hydraulic shut-off valves with the optional PSW shut off
tank controller switch. Distinguishing Features & Operating Benefits: Outstanding
toughness, durability. Designed for 30,000+ operating hours. ***Adjustable pressure boost
between 40-120 PSI.***

Aquatec CDP-6800 Booster Pump.

6800 Series (Low Flow). For membranes ***up to 50 GPD.***


--
Boomer

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Former US Army Bomb Technician (EOD)
Member; IABTI, NATEODA, WEODF, ISEE & IPS

If You See Me Running You Better Catch-Up


"Pszemol" wrote in message ...
: "Boomer" wrote in message
...
: I do not know what you mean by cycle. A booster pump should keep a constant pressure on
: the RO membrane. Cycling would be self-defeating, for if the pressure changes, do to a
: on-off phase, there would be a continuous pressure difference on the membrane.
:
: Or are you talking about a RO container pressure pump, that keeps made RO water in a
: container at x pressure to pump to y place.
:
: OK, more details...
: I have got Aquatec DDP5800, what they call "a demand/delivery pump".
: Hooked it up to my KENT 10gpd barebone RO system and turned the pump on.
: There was a pressure gauge in between the pump and the prefilters...
:
: When the pump was cycling on and off on the limit switch I saw the gauge
: going from the 40PSI (my tap water static pressure) to 65-70 PSI the moment
: the pump was on. 1/4, maybe 1/8 of the second later the pump turned off itself on
: the pressure switch and the pressure started decreasing to the 40PSI when the
: pump turned itself on again... This cycling seem to be due to the fact the pump
: had large capacity and pumped pressure high up really quick reaching the limit.
: The water did not have the way to escape through the RO filter that quickly so
: the pump turned off. When the pressure relatively slowly dropped back to the
: 40PSI the pump turned itself back again...
:
: I almost feel like I need a "water capacitor", using kind of electrical analogy...
: Some flexible device/container which could take the pressure from the pump
: and release it over time feeding the need for water of the RO filter... Or a much
: smaller capacity pump which will just barely keep up with RO filter demand.