PuriFresh®

 

 

 

INTEGRATED HEAT RECOVERY VENTILATOR/ HEPA FILTER

 

US PATENTS 6,257,317; 6,289,974

 

 

INSTALLATION MANUAL AND OPERATING INSTRUCTIONS

 

 

CAUTION:

READ AND UNDERSTAND THIS MANUAL THOROUGHLY BEFORE INSTALLING OR OPERATING THE UNIT!

 

 

 

 

 

 

ElasTek, Inc.

2 Chippewa Court

Madison, WI 53711

Telephone:        608-238-2039

Facsimile:         608-238-0270

E-mail:              inquire@purifresh.com

Internet Address: www.purifresh.com

 

  Made in the USA
I.  INTRODUCTION

 

                According to the American Lung Association and the U.S. Environmental Protection Agency, the three major strategies for reducing indoor air pollution (in order of overall effectiveness) are:

           

1.     Source Control

2.     Ventilation

3.     Air-Cleaning

 

Most products on the market are console HEPA filters and only use air-cleaning – the least effective strategy.  The PuriFresh® Integrated Heat Recovery Ventilator/ HEPA Filter implements all three strategies.  It HEPA filters fresh, outdoor air, eliminating pollen, mold spores, soot, and smoke particles, controlling a major source of pollution, especially for the allergy or asthma sufferer.  It provides ventilation, bringing in fresh air and exhausting stale air, eliminating odors, chemical vapors, and hazardous gasses that might otherwise accumulate indoors.  It also cleans indoor air, filtering out very fine particles that are most hazardous to humans.  In addition, the innovative HEPA Heat Filter conditions the fresh air through heat and moisture exchange, maintaining a comfortable and healthy indoor environment year round.

If you are an allergy or asthma suffer, you probably already have an air-cleaning device in some rooms.  Air cleaners work best when doors and windows to a room are kept closed.  Yet, for adequate ventilation, the American Lung Association recommends that you leave doors between rooms open most of the time and that you leave some windows partially open when possible.  The PuriFresh® HEPA Filtered Heat Recovery Ventilator, installed in a room, provides all the fresh air required for a room, allowing you to keep the windows and doors closed!  All of the fresh air provided is filtered through a true HEPA filter.  In addition, the fresh air is conditioned by heat and moisture exchange, giving you a year round refuge from pollution, allergens and stale air.

 

Product Specifications:

 

Size & weight                           16” x 13” x 7 ½”, approximately 28 pounds.

 

HEPA Heat Filters                   true HEPA medium filters 99.97% of 0.3 micron

particles.  Also act as heat exchangers.  Replaceable yearly or as needed.

 

Power                                      80 Watts (max.)

 

            Fresh air flow                           40 CFM (Cubic Feet per Minute) (max.)

 

            Heat exchange              75% (sensible effectiveness) at 40 CFM

 

 

II.  Operating Principle

 

          Each unit has two blowers.  One exhausts stale air from the room to the outside and the other draws fresh air into the room from outside.  Each unit also has four “HEPA Heat Filters” which are identical to conventional HEPA filters in material and fabrication.  These are located directly under the exterior cover.  The stale air is forced through a “rotating air switch”, then through two HEPA Heat Filters before leaving the unit to the outside.  The position of the air switch determines which two HEPA Heat Filters have stale air flow.  The fresh air is drawn in through the remaining two HEPA Heat Filters, then through the rotating air switch before going through the blower and entering the room.  Viewing any one of the four HEPA Heat Filters in time, stale air flows out, followed by fresh air in, and so on, as the rotating air switch turns.  This “breathing” action, caused by the rotating air switch, causes the HEPA Heat Filter to act as a heat and moisture exchanger.  In winter, the warm moist stale air deposits heat and moisture on the HEPA Heat Filter.  When the flow reverses and cold dry fresh air passes through it, the heat and moisture is transferred to the fresh air.  In summer, the same principle works to keep heat and moisture out of the room.

 

 

 

                A significant advantage of the oscillating flow is that the filters are partly self-cleaning.  Microscopic particles of dust or smoke penetrate deeply into the fibrous filter medium and are trapped, even when flow reverses.  Large dust particles, however, come to rest on the surface of the medium.  These particles are blown off the surface when flow reverses.  The filters require no maintenance between the recommended one-year interval for changing.

            Since the filters are also the heat exchangers and are replaced yearly, there is no need to clean heat exchangers.  This is a significant problem with any other Heat Recovery Ventilator on the market today.  The many narrow and deep channels in the current heat exchanger designs are essentially impossible to thoroughly clean.

 

III.  INSTALLATION

 

            Open the box.  Check to see that you have the following:

1.     The PuriFresh® unit.

2.     One black open cell foam gasket block 2” x 2” x 36”.

3.     One sash-retaining angle with screw hardware.

4.     Two pieces of corrugated plastic board 8” x 12” x 3/16”.

5.     Four sheet metal screws.

6.     One hex wrench.

            For installation, you will need a screwdriver, a utility knife, a ruler, and a small drill for making a pilot hole.

            Figure 1 shows a perspective view of the unit with the mounting brackets labeled. 

Figure 1

 

INSTALLATION IN A WINDOW

 

          The unit can be installed in any double hung window with a width between 20 and 40 inches. DO NOT INSTALL IN A WINDOW ABOVE A SIDEWALK OR ANYWHERE SOMEONE MAY BE BELOW WHO CAN BE INJURED OR KILLED IF THE UNIT OR A TOOL FALLS OUT DURING INSTALLATION. Select a window where the cord can be plugged into a three-pronged outlet directly.  The use of an extension cord is not recommended.  If the outlet is not three pronged, have a qualified electrician convert it.  Open the window sash approximately 10 inches or more.  Holding the unit securely, place the unit into the window with the bottom of the unit resting on the stool and the lower bracket up against the outer edge of the stool, as shown in Figure 2.  While continuing to hold the unit securely, lower the sash until it comes to rest in the position shown in Figure 2.   Gradually release your grip on the unit, making sure that it is secure before completely letting go of it.   

 

Figure 2

 

            If the window also has a storm window, the stool will often be below the level of the storm window frame.  This will prevent proper installation of the unit since it must be level.  Referring to Figure 3, add a wood board of the proper thickness along the entire length of the stool so that the top of this wood board is as high or higher than the storm window frame.  The board should be fastened securely to the stool with screws or nails.

               

         

Figure 3

                After the unit is in place in the window, the sash retaining angle, supplied with the unit, should be placed as shown in Figure 4.  It is important that the sash retaining angle be used since it prevents the window from accidentally being opened with the unit in place.  The unit is held as a cantilever.  If the window is accidentally opened, the unit will fall out of the window!

            Now take the foam gasket and insert it as shown in Figure 4 between the sash and the upper window glass to seal this opening.  Cut off any excess length of the gasket.

Figure 4

            There are two pieces of corrugated plastic sheet supplied with the unit which serves to seal and insulate the openings on either side of the unit.  Measure the widths of the openings, L1 and L2, as shown in Figure 5.  Measure these openings as accurately as possible, preferably to the nearest 1/16 of an inch.

Figure 5

            Take on of the sheets of corrugated plastic.  Measure and mark a line a distance L1 from the edge adjacent to the two mounting holes, as shown in Figure 6.  With a straight edge and a utility knife, cut the plastic along that line. Repeat this procedure for the opening on the other side of the unit, cutting the other piece of plastic to the width L2.  Use a cutting board, or the like, to prevent damage to a nice tabletop.

 

 

Figure 6

            Take the two cut pieces of plastic and attach them to the side bracket as shown in Figure 7 with the four sheet metal screws supplied.  Small wood screws  (not supplied) can be used to secure the plastic to the sash.

            To improve appearance and/or security, the cut plastic pieces can be replaced with pieces of wood.  Any lumberyard can cut the pieces of wood.

               

Figure 7

            The unit is now installed.  Plug the power cord into the electric outlet and turn it on.  Turn the power switch clockwise past the click to turn the unit on high.  To lower the blower speed, continue turning the switch clockwise.

            Note that the installation you have just performed does not produce an air tight seal around the unit.  There are a number of cracks that we strongly suggest you seal with tape, rope caulk, etc., available at any hardware store.  The unit provides HEPA filtration of the air it brings into the room.  It would defeat the purpose of the unit if a significant amount of air is infiltrating in through cracks.  This infiltration will be particularly high on windy days.

            To remove the unit from the window, perform the above in reverse order.

 

INSTALLATION THROUGH A WALL

 

            The unit can be installed through any exterior wall with a total thickness of eight inches or less.  Cut and frame a rectangular opening 16 ½ inches wide by 7 ¾ inches high through the wall.  Follow local building codes.  Choose a location close enough to a grounded three-pronged outlet such that the unit can be plugged in without the need for an extension cord.  Place the PuriFresh® Integrated Heat Recovery Ventilator and HEPA Filter into the opening.  Caulk and seal it in place.  The side brackets can be removed before installation along with the machine screws used to attach them.  If this is done, place some tape over the screw holes.

            With the unit permanently in place in an exterior wall, the HEPA Heat Filters can only be replaced from the outside of the building. 

 

IV.  HEPA HEAT FILTER REPLACEMENT

 

Figure 8

           

To replace the HEPA Heat Filters, the unit must be removed from the window, unless the unit can be easily accessed from the outside, such as, in a ground floor installation.  We recommend that the filters be replaced yearly, preferably at a time of year when there is a low concentration of allergens outdoors.  If the unit has been subjected to a driving rain from a storm, we recommend that the filters be inspected for possible water damage.

Figure 7 shows an exploded view of the exterior of the unit.  To replace the HEPA Heat Filters, remove the rear cover by removing the two screws holding it in place.  Use the hex head wrench provided with the unit.  A peal and stick foam gasket is applied to the interior of the rear cover.  Remove the four old HEPA Heat Filters and replace them with four new ones.  Each filter is in a cardboard box with two openings on opposite sides.  One opening has a smooth frame around it with no cuts.  When installing a filter, have this opening face the exterior cover. Note that the six filter stops do not have to be removed.  If one comes loose when removing a filter, simply put it back in place.  Inspect the foam gasket.  If it appears worn or if it appears to have lost its elasticity, order a new one and replace it.  First, peal off the old gasket.  Then peal off the backing of the new gasket and carefully place it inside the rear cover in the same position as the old gasket.  Replace the rear cover.  Replace the two screws, which secure the rear cover.  Note that the rear cover must be pushed toward the unit, compressing the gasket, while the screws are inserted.  It is helpful to put the unit on a surface with the exterior cover facing up.  In this position, the exterior cover can be pushed down with one hand while the screws are inserted with the other hand.

 

V.  IMPORTANT NOTES

 

          To be most effective, the unit should be run continuously with the doors and windows to the room closed.  Consult your local hardware store for advice and products that will seal cracks, electrical outlet covers, etc.  Reducing infiltration of unfiltered air is important. 

The unit can be operated with a timer.  A timer, which accepts a three-pronged plug, must be used.

            In addition to using the product as recommended above, it is important to keep the room clean.  Dust and vacuum weekly.  Wash the bedding in hot water every two weeks.  Use mattress covers, if needed, and follow the directions for use.

            You now have a true refuge from allergens, stale air and pollution, year round. 

We welcome any comments or concerns you may have so that we can help you use our product most effectively.

 

VI. WARRANTY

 

          The unit has a full one year warranty on manufacturers defects covering all parts and labor for repair.  The warranty does not cover damage to the unit caused by the consumer due to improper handling or installation.  The warranty also does not cover damage to the unit when run in unusually corrosive or dusty environments such as, for example, running the unit in a room where wood floors or furniture or cabinets are being sanded.  If you are experiencing a problem, first contact us by phone, mail of fax.  If we can not assist you in solving the difficulty, we will make arrangements to have it shipped to us for repair or replacement.