Perpetua™ Whole-House Filter
Owner's Manual and Service Guide
Model 7 · Form OM-7 · Revised March 2007 (reprint)
Contents
1. Identifying Your Unit
Where is the serial number?
The serial number is located on the faceplate.
How do I read the serial number?
Serial format: 7-YYWW-NNNNN.
2. Installation
Install the Perpetua on the cold water main after the meter and before any branch. Provide a shutoff on each side. The unit must be mounted upright with clearance below the bowl equal to the bowl height plus four inches for element service.
What is the maximum inlet pressure?
Maximum inlet pressure 100 psi.
What water temperature is the unit rated for?
For cold water service only. Protect from freezing.
The unit bangs when the backwash valve closes.
If noise occurs on backwash, adjust the dashpot screw on the valve body.
What are the inlet and outlet threads?
Inlet and outlet: 3/4 in NPT.
How is the unit mounted?
Mount securely to a wall stud using the bracket provided.
Does the backwash drain need an air gap?
Provide an air gap at the backwash drain connection.
3. Safe Service Practice
How do I remove the bowl without flooding the basement?
Turn the bypass lever to BYPASS and drain the bowl before removal.
4. The Perpetua Element
The Perpetua Element is a sintered ceramic candle with a silver-impregnated core, protected by a string-wound prefilter wrap. It is the heart of your unit and is designed to be cleaned and returned to service many times.
How do I clean the ceramic element?
Scrub the element under running water with the supplied nylon brush. Do not use soap or bleach.
How many times can the ceramic element be cleaned before it must be replaced?
The element may be cleaned many times. Replace when the wall becomes thin. Use the gauge supplied.
Does the silver core wear out?
The silver core lasts the life of the element and requires no service.
The water is cloudy after I put the element back. Is it broken?
Some cloudiness after installation is normal and will clear.
The element retaining nut will not come off.
Loosen the retaining nut by turning counter-clockwise (see diagram).
How long does an element last?
With proper care the element will provide many years of service.
I have a spare element in the tube. Is it still good?
Spare elements should be stored in their original packaging.
5. Prefilter Wrap
What replaces the cotton prefilter wrap, and where do I get one?
Replace the prefilter wrap every three months. Use only Wendorf Genuine Wrap P-W7. Other wraps will void the guarantee.
6. Seals and Gaskets
Which bowl O-ring does my unit take?
Bowl O-ring, part P-O7, 3.5 in x 3/16 in.
How tight does the bowl go?
Tighten the bowl by hand until snug. Do not use a wrench.
What lubricant goes on the O-ring?
Apply a thin coat of silicone grease to the O-ring before reassembly.
What seals the drain plug?
Drain plug: 1/4 in NPT. Use PTFE tape.
Is the head gasket the same as the bowl O-ring?
Head gasket: part P-G7H.
7. The Cycle Head
The Cycle Head performs an automatic reverse-flow backwash of the element once daily. It is factory set for 2:00 AM. The timer is driven by a synchronous motor and requires a 120 V outlet within four feet of the unit.
The backwash timer pin broke. What replaces it?
Timer pin: part P-T7P.
The Cycle Head motor has failed. What is the replacement?
Timer motor: part P-M7. Replace as an assembly.
What does the green light on the Cycle Head mean?
The green indicator shows the unit is in continuous operation.
8. Water Conditions and Performance
What is the rated flow?
Rated flow 8 gallons per minute.
Flow has dropped. What do I check?
Reduced flow indicates the wrap or element needs service.
The water tastes metallic.
A slight taste after installation is normal. Flush the unit.
How much water does the element handle between cleanings?
Clean the element approximately every six months.
Is the unit safe on chlorinated municipal water?
Suitable for municipal water.
10. Seasonal Shutdown
How do I winterize the unit?
For seasonal shutdown, drain the bowl and remove the element.
11. Housing and Bowl
The bowl is cracked. Can it be repaired?
A cracked bowl must be replaced. Contact Wendorf Water Company for a replacement bowl.
12. Parts List
| Part | Description |
|---|---|
| P-E7 | Perpetua Element, ceramic, with wrap |
| P-W7 | Genuine Prefilter Wrap (pkg of 4) |
| P-O7 | Bowl O-ring |
| P-G7H | Head gasket |
| P-M7 | Timer motor assembly |
| P-T7P | Timer pin (pkg of 3) |
| P-G7 | Element wall gauge |
| P-B7 | Nylon cleaning brush |
| P-BR7 | Wall bracket with lag bolts |
Order from your authorized Wendorf dealer or direct from the factory. Parts are supplied at no charge under the Guarantee.