Groco Pressure Tanks - 4.5 GAL Pressure Tank | PST-4
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You have 30 days to request a return. All sale items are final sale.
Pressure Tanks
GROCO PST-4 Pressure Storage Tank
A pneumatic pressure charge, matched to the pump cut on pressure prevents water logging by separating the air charge from system water pressure with a rubber bladder. The result is smooth pressure delivery, even temperature mix in showers, and reduced pump cycling. Tanks may be mounted in any position, and anywhere in the cold water plumbing after the pump. PST tanks may be used for fresh or salt water. Mount hardware is included. PST-6 has a pump stand for mounting PJR, WSC-60 or WSC-80 pump. Maximum rated PSI is 100.
- Brand: Groco
- Manufacturer part #: PST-4
- Sold as: EA
Model Details
PST-4 is a stand-mounted pressure storage tank with 14-gallon nominal tank volume and a 3/4-inch NPT plumbing connection. GROCO lists 4.3 gallons of drawdown for a 30/50 PSI operating cycle. Drawdown is the usable water delivered between pump cycles, not the total tank volume.
Parts Desk Insight
Set the air precharge to match the pump cut-on pressure, checking it with no water pressure in the tank. Size the tank by the pump operating pressures and required drawdown rather than the gallon figure alone. Leave access to the air valve for the manufacturer-recommended monthly pressure check.
GROCO PST installation guidance | Current model and drawdown table
Shipping information
In-stock and OEM parts: ship same or next business day.
Available items are ready for pickup or shipping between one and three days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.