Pentair MT Sizes 500 User Manual

Installation and Operation Instructions for

MegaTherm

Pool Heating Boiler

Model MT

Sizes 500 - 1825

IMPORTANT: Store these instructions in the

pocket provided on the heater

FOR YOUR SAFETY: This product must be installed and serviced by a

professional service technician, qualified in hot water boiler installation and maintenance. Improper installation and/or operation could create carbon monoxide gas in flue gases which could cause serious injury, property damage, or death. Improper installation and/or operation will void the warranty.

If the information in this manual is not

WARNING

followed exactly, a fire or explosion may result causing property damage, personal injury or loss of life.

Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance.

WHAT TO DO IF YOU SMELL GAS

• Do not try to light any appliance.

• Do not touch any electrical switch; do not use any phone in your building.

• Immediately call your gas supplier from a nearby phone. Follow the gas supplier's instructions.

• If you cannot reach your gas supplier, call the fire department.

Installation and service must be performed by a qualified installer, service agency, or gas supplier.

Assurez-vous de bien suivres les instructions données dans cette notice pour réduire au minimum le risque d’incendie ou d’explosion ou pour éviter tout dommage matériel, toute blessure ou la mort.

Ne pas entreposer ni utiliser d’essence ni d’autres vapeurs ou liquides inflammables dans le voisinage de cet appareil ou de tout autre appareil.

QUE FAIRE SI VOUS SENTEZ UNE ODEUR DE GAZ:

• Ne pas tenter d’allumer d’appareils.

• Ne touchez à aucun interrupteur. Ne pas vous servir des téléphones dansle bâtiment où vous vous trouvez.

• Appelez immédiatement votre fournisseur de gaz depuis un voisin. Suivez les instructions du fournisseur.

• Si vous ne pouvez rejoindre le fournisseur de gaz, appelez le sservice des incendies.

L’installation et l’entretien doivent être assurés par un installateur ou un service d’entretien qualifié ou par le fournisseur de gaz.

AVERTISSEMENT

P/N 472643 Rev A - 05/22/06

IMPORTANT SAFETY INSTRUCTIONS

READ AND FOLLOW ALL INSTRUCTIONS

SAVE THESE INSTRUCTIONS

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Pentair Water Commercial Pool and Spa

TABLE OF CONTENTS

SECTION 1. General Information

1.1 Introduction................................................... 3

1.2 Heater Identification ..................................... 3

1.3 Primary/Secondary Pump and Piping........... 3

1.4 Certifications................................................. 3

1.5 Engineering Assistance ................................ 3

SECTION 2. Installation

2.1 Boiler Placement .......................................... 4

2.2 Installation of Indoor Boilers ......................... 4

2.2.1 Combustion Air Supply ................................. 4

2.2.2 Venting ......................................................... 5

2.2.3 Common Venting System

Test Procedure ............................................. 6

2.2.3 Instructions Relatives au Test des

Systèmes à Évent Commun .........................6

2.3 Installation of Outdoor Boilers ...................... 7

2.4 Gas Supply and Piping ................................. 7

2.5 Electrical Wiring............................................ 8

2.6 General Piping Instructions .......................... 9

2.7 Boiler By-Pass Piping ................................... 9

2.8 Temperature Sensor Placement

and Installation ............................................ 10

2.9 Automatic Chlorinators ...............................10

SECTION 3. Operation

3.1 Controls - General ...................................... 11

3.2 Initial Start-Up ............................................. 11

3.3 Safety Shutoff Component Checkout ......... 12

3.4 Inlet Temperature and

Temperature Rise Adjustment .................... 12

3.5 Heater Shut Down ...................................... 13

3.6 Spring and Fall Operation

Stand-by Service ........................................13

3.7 Winter Operation Complete Shutdown ....... 14

3.8 Time Clock Operation................................. 14

3.9 Therapeutic Pools (Spas) ........................... 14

SECTION 4.

Maintenance..............................................15

SECTION 5.

Troubleshooting .......................................16

SECTION 6.

Parts Description and Order Numbers ................17

Pentair Technical Support

Sanford, North Carolina (8 A.M. to 5 P.M.)

Phone: (800) 831-7133 Fax: (919) 566-8920

Moorpark, California (8 A.M. to 5 P.M.) Phone: (800) 831-7133 Fax: (800) 284-4151

Web sites: visit www.pentairpool.com and www.staritepool.com

MegaTherm Commercial Pool Heating Boiler

Page 3

SECTION 1. General Information

1.1 Introduction

This manual provides information for the installation and operation of MegaTherm model MT pool heating boilers. It is strongly recommended that all application and installation procedures be reviewed completely before proceeding with the installation. Consult Pentair Commercial Pool and Spa, or your local sales representative, with any problems or questions regarding this equipment. Experience has shown that most problems are caused by improper installation, not system design.

Some accessory items are shipped in separate packages. Verify receipt of all packages listed on the packing slip. Inspect everything for possible damage upon delivery, and inform the carrier of any shortages or impairments. Any such claims should be filed with the carrier. The carrier, not the shipper, is responsible for shortages and damage to the shipment whether visible or concealed.

WARNING

The MegaTherm model MT commercial pool heating boiler must be used on potable water only. For heating pools containing salt water, a specially equipped heater must be used; consult your distributor or factory representative. The pool heating boiler must be installed in accordance with the procedures

The warranty does not apply to heaters not installed or operated in accordance with these procedures. Consult local building and safety codes before proceeding with work. The installation must conform to the requirements of the authority having jurisdiction or, in the absence of such requirements, to the latest edition of the National Fuel Gas Code; ANSI Z223.1, National Electrical Code ANSI/NFPA 70. In Canada, the installation must conform with the latest edition of CSA-B149.1 requirements.

When required by the authority having jurisdiction, the installation must conform to

American Society of Mechanical Engineers safety codes for controls and safety devices for automatically fired heaters No. CSD-1, and in Canada CGA 3.3. Any modification of the heater, its gas controls, gas orifices, wiring or drafter diverter may void the warranty. If field conditions require such modifications, consult factory.

1.2 Heater Identification

Consult rating plate on the heating boiler. Shown below is a breakdown of the model nomenclature. Commercial pool heating boilers are available in two configurations: an indoor version and an outdoor version. Outdoor models are not available in Canada.

1.3 Primary/Secondary Pump and Piping

All models are supplied with integrally mounted pumps. The 1825 models use a 3/4 HP pump and all other models are supplied with 1/2 HP pumps. These pumps are sized for the pressure drop through the heat exchanger and through the bypass piping as shown in Figure 10.

Any deviations from the arrangement shown may increase the head on the pump, reduce flow and hinder performance (see Section 2.7). For spas see Section

3.9.

This piping arrangement and the integral pump allow hot water to be recirculated to the heater inlet, thus raising the inlet temperature and greatly reducing condensation.

1.4 Certifications

All models are design-certified by CSA for natural or propane gas and conform to ASME Code requirement for 160 PSI water pressure.

1.5 Engineering Assistance

Consult the factory or distributor regarding any questions or problems which arise in the specification, installation or operation of this equipment. An experienced engineering staff is ready to assist in assuring the proper performance and application of this products.

1 2 3 4 5 6 7 8 9 10 11 12 13 14

MODEL

MT-POOL

Figure 1. Heater Identification (model nomenclature).

SIZE

BTU/HR X 1000

0500 0600 0715 0850 0999 1010 1200 1430 1670 1825

I-INDOOR E-OUTDOOR

FUEL

N-NATURAL P-PROPANE

IGNITION

04-SPARK 110V 09-SPARK 24V 11-SPARK 24V 16-STND. PILOT

FIRING MODE ON/OFF

VERSION

1 - 8 TUBE B-10 TUBE

HEAT EXCHANGER

C-GLASS LINED/COPPER N-GLASS LINES/CU-NI K-BRONZE/COPPER S-BRONZE/CU-NI

REVISION

P-PUMP (U.S.) Q-PUMP (CAN)

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Pentair Water Commercial Pool and Spa

SECTION 2. Installation

2.1 Boiler Placement

The pool heating boiler must be placed to provide specific clearances on all sides for maintenance and inspections. There must also be minimum distances maintained from combustible surfaces. These clearances also apply to noncombustible materials because the pool heating boiler requires air circulation for proper operation.

The pool heating boiler should be mounted on a level surface. An integral base for an installation on combustible flooring is provided as standard equipment on special base rails part number 10539000 must be used for combustible flooring.

Do not install a pool heating boiler on carpeting.

Under the national Fuel Gas Code, ANSI Z223.1, it is permissible to place the boiler on floors other than noncombustible when the installation complies with the American Insurance Code. Figures 2, 3, 4 and 5 show common installation on combustible flooring.

outdoor models. For indoor models,

Clearance Indoor Outdoor

from in.

Top 30

Water Conn. side 12*

Pump side 6*

Front Alcove* unobstructed

Rear 8

Vent pipe** 6

Hot water pipes per code per code

* Water connection and pump side clearances of 24" (610mm)

and front clearances of 48" (1219mm) will allow easier service access.

** Using type B vent (refer to Manufacturer's Instructions).

Table 1. Minimum boiler clearances from

adjacent surfaces.

762

305

152

203

152

in.

unobstructed

610

- - -

2.2 Installation of Indoor Boilers

Locate the pool heating boiler to provide adequate clearance for inspection and service on all sides. See Table 1. For alcove installation, see Figure 6.

Install indoor heaters on a waterproof floor with an adequate floor drain and a 6" (152mm) minimum curb on all four sides to protect the building if heater repairs are required. The manufacturer will not be

held liable for any water damage in connection with this boiler.

2.2.1 Combustion Air Supply

The heater location must provide sufficient air supply for proper combustion and ventilation of the surrounding area as outlined in the latest edition of ANSI standard Z223.1, and any local codes that may be applicable. Inadequate combustion air supply may result in incomplete combustion, sooting of the heat exchanger, and unsafe operation of the boiler.

a. Conventional Ventilation

In the United States, the most common of these requirements specify that boiler rooms should be provided with two permanent air supply openings communicating directly through the wall to outside air one within 12 inches (305mm) of the ceiling, and the other within 12 inches (305mm) of the floor. Each opening should have a minimum free area of one square inch (6.5 sq. cm) per 4,000 BTU/hr input of the total input rating of all appliances in the enclosed area. See Table 2 for recommended air supply for each model. An

Figure 2. Typical Boiler Installation on Concrete Slab.

Figure 3. Typical Boiler Installation on Roof Using

Raised Platform (wood).

improperly ventilated equipment room can get excessively hot and cause accelerated deterioration of controls and electrical components.

In Canada, Table 2 does not apply. Consult local building codes or, in the absence of such requirements, follow CSA-B149.1 standard.

MegaTherm Commercial Pool Heating Boiler

12345678901234567890

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Figure 4. Typical Boiler Installation on Roof

Using 4x4 Stringer.

Base must extend out min. 12" (305mm) on all sides of heater frame.

20 ga. min. galvanized sheet metal under entire heater.

234567890123456789

CLOSET INSTALLATION

(UNACCEPTABLE)

A closet is any 4 sided enclosure which is less than 16* times the total volume of all the gas fired appliances within the enclosure.

234567890123456789

* When the ceiling height exceeds 8 feet, you are only allowed to consider 8 feet when calculating the total volume of the enclosure.

Water

Heater

234567890123456789

Water

Heater

ROOM INSTALLATION

(ACCEPTABLE)

A room is any enclosure which is at least 16* times greater than the total volume of all the gas fired appliances within the enclosure.

ALCOVE INSTALLATION

(ACCEPTABLE)

An alcove suitable for the installation of a water heater is a restricted section of a room not separated from the room by a door or partition and which meets the minimum clearances for the specific model water heater listed below.

Figure 6. Alcove Installation.

Blocks must provide solid base and be braced so they cannot slip out of place. Air openings in blocks must be arranged to provide unobstructed opening through entire width or length of base.

Figure 5. Installation on Concrete Blocks or Tile.

b. Forced-Air Ventilation

In the United States: any equipment which exhausts air from the boiler room can deplete the combustion air supply or reverse the natural draft action of the venting system. This could cause flue products to accumulate in the boiler room. Additional air must be supplied to compensate for such exhaust. The information in Table 2 is not applicable in installations where exhaust fans or blowers of any type are used. Such installations must be designed by qualified engineers.

In Canada: follow Canadian standard, CSA-B149.1 or local codes.

If a blower or fan is used to supply air to the boiler room, the installer should make sure it does not create drafts which could cause nuisance shutdowns of the pilot. If a blower is necessary to provide adequate combustion air to the boiler, a suitable switch or interlock must be wired into the heater control circuit to prevent the heater from firing unless the blower is operating.

The boiler must be completely isolated and protected from any source of corrosive chemical fumes such as trichlorethylene, perchloroethylene, chlorine, etc.

Concrete blocks or tile min. 7" (178mm) high with 3" (76mm) min. air openings.

2.2.2 Venting

The MegaTherm boiler has a built-in draft diverter for natural draft operation and must not be connected to any portion of a mechanical draft system under positive pressure. The flue outlet must be connected to a clear, unobstructed vent of adequate capacity ending above the highest point of the building with an approved vent cap. The venting system should be installed according to the latest edition of ANSI Z223.1 and/or, in Canada, CSA-B149.1 and any local codes having jurisdiction.

Do not weld or fasten the vent pipe to the boiler drafthood. The weight of the stack must not rest on the boiler.

The drafthood and boiler top must be easily

removable for normal boiler service and inspection.

IMPORTANT NOTE: Do not use sheet metal screws at the snap lock joints of Type B gas vents.

Avoid using long horizontal runs of the vent pipe, and too many 90° elbows, reductions or restrictions. Horizontal runs should have at least a 1/4" (6mm) rise per foot in the direction of flow. A vent connector should be supported for the design and weight of the material used to maintain clearances and prevent physical damage and separation of joints.

Avoid terminating boiler vents near air conditioning or air supply fans. The fans can pick up exhausted flue products from the boiler and return them inside the building creating a possible health hazard. A minimum of 4 feet (1.2m), in Canada 6 feet (1.8m), horizontal distance must be maintained from electrical meters, gas meters, and relief equipment.

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Pentair Water Commercial Pool and Spa

Always use double-wall or insulated vent pipe (Type B or equivalent). In cold weather, uninsulated outside vents can chill the rising flue products blocking the natural draft action of the venting systems. This can create a health hazard by spilling flue products in the boiler room.

Avoid oversized vent piping or extremely long runs of pipe which may cause excessive cooling and condensation. Rule of Thumb: the total length of the vent, including the connector and any offset, should not exceed 15 feet (4.6m) for every inch (25mm) of vent diameter. Longer total lengths shown in venting tables are based on maximum capacity, not condensation factors.

When the installation of a draft fan is necessary in connecting a venting system to a MegaTherm boiler, the installation should be engineered by competent personnel following good engineering practices. The draft fan supplier should be consulted for correct size. The installation should be in accordance with the latest edition of ANSI Z223.1 and/or, in Canada, CSA-B149.1 and any local codes having jurisdiction. When a draft fan is installed, a suitable draft switch must be wired into the boiler control circuit at terminal designated "Field Interlock" to prevent firing of the boiler unless a positive draft has been established.

2.2.3 Common Venting System

Test Procedure

At the time of the removal of an existing heater, the following steps shall be followed with each appliance remaining connected to the common venting system. During the testing of each unit, the other appliances remaining connected to the common venting system should not be operated.

1. Seal any unused openings in the common

venting system.

2. Visually inspect the venting system for proper

size and horizontal pitch. Determine that there is

no blockage or restriction, leakage, corrosion, or

other deficiencies which could cause an unsafe

condition.

3. Insofar as it is practical, close all building doors

and windows. Also close all doors between the

space in which the appliances remaining

connected to the common venting system are

located and the other spaces of the building. Turn

on any clothes dryer and any appliance not

connected to the common venting system. Turn

on any exhaust fans, including range hoods and

bathroom exhausts, so they will operate at

maximum speed. Do not operate a summer

exhaust fan. Close all fireplace dampers.

4. Place in operation the appliance being inspected.

Follow the lighting instructions for the unit.

Adjust the thermostat so the appliance will

operate continuously.

5. Test for spillage at the draft hood relief opening after 5 minutes of main burner operation. Use the flame of a match or candle, or smoke from a cigarette, cigar, or pipe.

6. After it has been determined that each appliance remaining connected to the common venting system properly vents when tested as outlined above, return doors, windows, exhaust fans, fireplace dampers and any other gas-burning appliance to their previous condition of use.

7. Any improper operation of the common venting system should be corrected so the installation conforms with the National Fuel Gas Code,

ANSI Z223.1 and/or CSA-B149.1 , Installation Codes. When resizing any portion of the

common venting system, the common venting system should be resized to approach the minimum size as determined using the appropriate tables in Appendix G in the National

Fuel Gas Code, ANSI Z223.1 and/or CSA-B149.1 Installation Codes.

2.2.3 Instructions Relatives au Test des Systèmes à Évent Commun

Au moment du restrait d’une chaudière existante,

les mesures suivantes doivent être prises pour chaque appareil toujours reccordé au système d’évacuation ne fonctionnet pas:

1. Sceller toutes les ouvertures non utilisées du systèmes d’évacuation.

2. Inspecter de façon visuelle le système d’évacuation pour déterminer la grosseur et l’inclinaison horizontale qui conviennent et s’assurer que le système est exempt d’obstruction, d’étranglement, de fuite, de corrosion et autres défaillances qui pourraient présenter des risques.

3. Dans la mesure du possible, fermer toutes les portes et les fenêtres du bâtiment et toutes les portes entre l’espace où les appareils toujours raccordés au système d’évacuation sont installés et les autres espaces du bâtiment. Mettre en marche les sécheuses, tous les appareils non raccordés au système d’évacuation common et tous les ventilateurs d’extraction comme les hottes de cuisinière et les ventilateurs des salles de bain. S’assurer que ces ventilateurs fonctionnent à la vitesse maximale. Ne pas faire fonctionner les ventilateurs d’été. Fermer les registres des cheminées.

4. Mettre l’appareil inspecté en marche. Suivre les instructions d’allumage. Régler le thermostat de façon que l’appareil fonctionne de façon continue.

5. Faire fonctionner le brûleur principal pendant 5 min ensuite, déterminer si le coupe-tirage déborde à louverture de décharge. Utiliser la

MegaTherm Commercial Pool Heating Boiler

Page 7

flamme d’une chandelle ou la fumée d’une cigarette, d’une cigare ou d’une pipe.

6. Une fois qu’il a été déterminé, selon la méthode indiquée ci-dessus, que chaque appareil raccordé au systéme d’évacuation est mis à l’air libre de façon adéquate. Remettre les portes et les fenêtres, les ventilateurs, les registres de cheminées et les appareils au gaz à leur position originale.

7. Tout mauvais fonctionnement du systéme d’évacuation commun devrait être corrigé de façon que l’installation soit conforme au National Fuel Gas Code, ANSI.Z223.1 et (ou) aux codes d’installation CSA-B149.1. Si la grosseur d’une section du système d’évacuation doit être modifiée, le système devrait être modifié pour respecter les valeurs minimales des tableaux pertinents de l’appendice G du National

Fuel Gas Code, ANSI Z2231.1 et (ou) des codes d’installation CSA-B149.1.

2.3 Installation of Outdoor Boilers

1. Locate the boiler to provide the clearances as listed in Table 1, “Minimum Boiler Clearances.”

2. Do not place the boiler in an enclosure or wall recess. Avoid locations where wind deflection off structures might cause downdraft. When such wind conditions are possible, place the heater at least 3 feet (0.9m) from the structures.

3. Never install the boiler under any kind of roof overhang. Do not place the boiler below or adjacent to any doors, windows, louvers, grills, etc., which connect in any way with an inhabited area of a building. This includes other structures such as garages or utility rooms (see Figure 7).

4. Although these models are CSA designed certified for outdoor installations, such installations are not recommended in areas where the danger of freezing exists unless proper precautions are taken for freeze protection.

Outdoor installations are not recommended in areas where the danger of snow blockage exists.

WARNING

Liquefied petroleum gas is heavier than air. Therefore, the pool heating boiler should not be installed in pits or other locations where gas could accumulate.

The boiler should be located a safe distance from

Propane gas storage and filling equipment. Consult local codes and fire protection authorities for advice on specific installation restrictions.

Boiler Each Opening*

Size square inches

500 125 600 150 715 179

850 213 1010 253 1200 300 1430 358 1670 418 1825 457

* Net Free Area. Check with louver manufacturers for net free area of louvers.

Correct for screen resistance to the net free area if a screen is installed. Check all local codes applicable to combustion air.

Area indicated is for one of two openings: one at floor level and one at the ceiling, so the total net free area could be double the figures indicated. For special conditions refer to the latest editon of ANSI Z223.1.

Consult factory if openings do not communicate directly through the walls with the outdoors.

Table 2. Minimum Recommended Air Supply to Boiler.

Figure 7. Incorrect Outdoor Installation.

square cm

806.5

967.8

1154.9

1374.3

1632.4

1935.6

2309.8

2696.9

2948.6

2.4 Gas Supply and Piping

Review the following instructions before

proceeding with the installation.

1. Verify that the boiler is fitted for the proper type of gas by checking the rating plate. MegaTherm boilers are normally equipped to operate below a 2000 foot (609.6m) altitude. Boilers equipped to operate at higher altitudes have appropriate stickers or tags attached, also printed information on rating plate.

2. Use the figures in Table 3 to provide adequate gas piping from the gas meter to the boiler.

3. A sediment trap (drip leg) must be provided ahead of the gas controls (see Figure 8). A manual gas shutoff valve must also be provided for service convenience and safety. Check the local codes.

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Pentair Water Commercial Pool and Spa

Distance from Gas Meter

Boiler or Last Stage Regulator

Size

500 1½" 2" 2" 600 1½" 2" 2½" 715 2" 2" 2½"

850 2" 2½" 2½" 1010 2" 2½" 3" 1200 2½" 3" 3" 1430 2½" 3" 3" 1670 2½" 3" 3 1825 2½" 3" 3½"

NOTE: These figures are for Natural Gas (.65 Sp. Gr.), and are based on 1/2" water column pressure drop. Check supply pressure with a manometer, and local code requirements for variations. For Propane Gas, reduce pipe diamter one size. An average number of tees and elbows have been taken into account.

0-100' 100-200' 200-300'

0-30.5m 30.5-61m 61-91.4m

Table 3. Gas Piping Sizes.

4. The boiler and its individual shutoff valve must be disconnected from the gas supply piping system during any pressure testing of that system at test pressures in excess of 1/2 psig (3.5kPa). The boiler must be isolated from the gas supply piping system by closing its individual manual gas shutoff valve during any pressure testing of the piping system at test pressures equal to or less than 1/2 psig (3.5kPa).

5. Provide gas supply pressure to the heater as follows:

Natural Gas Propane Gas

In. W.C.

Max. 10 Min. 6.5

kPa

2.5

1.6

In. W.C.

14 11

kPa

3.4

2.7

NOTE: the heater and all other gas appliances sharing the boiler gas supply line must be firing at maximum capacity to properly measure the inlet supply pressure. Low gas pressure could be an indication of an undersized gas meter and /or obstructed gas supply line.

Gas Supply

To Equipment Inlet

Nipple

Cap

Inlet

Tee Fitting

3" (76mm) Min.

6. The correct burner manifold gas pressure is stamped on the rating plate. The regulator is preset at the factory and normally requires no further adjustment. The gas manifold and control assembly is

factory tested and conforms to the safe lighting and other performance criteria specified in the latest editions of ANSI Z21.13.CSA4.9 Low Pressure Boiler Standard.

Before operating the boiler, the complete gas

supply system and all connections must be tested for leaks using a soap solution. Do not use raw flame.

Caution

Since some leak test solutions (including soap and water) may cause corrosion or stress cracking, the piping must be rinsed with water after testing, unless it has been determined that the leak test solution is noncorrosive.

2.5 Electrical Wiring

WARNING

The boiler must be electrically grounded in accordance with the most recent edition of the National Electrical Code, ANSI/NFPA 70. In Canada, all electrical wiring to the boiler should be in accordance with the latest edition of CSA C22.1 Canadian Electrical Code, Part 1. Do not rely on the gas or water piping to ground the metal parts of the boiler. Plastic pipe or dielectric unions often isolate the boiler electrically. Service and maintenance personnel who work on or around the heater may be standing on wet floors and could be electrocuted by an ungrounded boiler.

Wiring diagrams are included in the information

packet provided with each unit.

1. All Model MT pool heating boilers need 115V 60Hz supply voltage unless specifically ordered otherwise.

2. The 1825 models are supplied with 3/4 HP pump motors. All other models are supplied with 1/2 HP pump motors. Consult the National Electrical Code or the Canadian Electrical Code regarding branch circuit requirements for equipment with these motors.

3. The boilers should be wired exactly as shown in the wiring diagram.

Figure 8. Sediment Trap Installation.

MegaTherm Commercial Pool Heating Boiler

Figure 9. Pressure Relief Valve Location.

IMPORTANT NOTE: The pool filter pump and

boiler must be electrically interlocked so the boiler cannot come on unless the pump is running and there is full flow in the filter piping where the boiler is connected. If the pool filter pump operation is intermittent the boiler must be shut off prior to pump shutdown. See paragraph heading Auxiliary Time Clock Wiring below. If the backwash operation is manual the boiler must be shut off manually during backwashing.

Auxiliary Time Clock Wiring:

If a time clock is used to control the filter pump operation, a separate switch or relay must be used to shut off the boiler at least

15 minutes before the filter pump is shut off. Wire the switch or relay (often called the Fireman Switch) to the terminals shown in the wiring diagram as “Field Interlock.”

4. All field installed electrical safety devices and all

field installed controllers (valve end switches, draft switches, relays, timers) can be connected to the boiler control to the terminals shown in the wiring diagram designated “Field Interlock.”

5. Field location of the temperature sensor is

described in Section 2.8.

Where the boiler is installed with a draft fan refer to the fan manufacturer's wiring diagram. The draft switch should be wired across the field interlock terminals in the boiler control panel.

2.6 General Piping Instructions

In addition to the bypass valve “B” and outlet valve “A” shown in Figure 10, an inlet valve “C” should be provided so that the heater can be readily isolated for service. All valves should be butterfly or ball style, Section 3.9.

150°F (66°C) in some cases, copper or CPVC are recommended materials for heater connection piping. PVC material may be used for the inlet valve and the piping upstream of it.

not gate valves. For spas application see

Since heater outlet temperatures can reach

Page 9

When pipe, fittings, grids or any other element of the filter system are made of plastic materials, they may be damaged by the momentary "back siphoning" of hot water from the heater when the filter pump stops running.

The pressure relief valve installed in the tapped opening provided in the outlet header (see Figure 9), must be piped, but not connected, to a drain or floor sink. The drain pipe must be the same size as the valve outlet and must pitch downward from the valve. Where no special setting of the relief valve is ordered, the factory will furnish a 75 psi setting.

The pressure relief valve lever must be tripped at least once a year to insure that waterways are clean. When manually operating lever, water will discharge through the drain line. Precautions must be taken to avoid contact with hot water and water damage.

2.7 Boiler By-Pass Piping

All MT series boilers, 500-1825 models, must be installed with bypass piping. Please use Figure 10 as your guide to plumb the bypass. For spas see Section

3.9.

The diverter valve in the main line, shown in dashed line in Figure 11, is optional and may be needed only if the distance to the heater is over 15'. Call the Service Department at 800-900-9276, extension 5406 for assistance.

All models are supplied with integral pumps, These pumps are sized for the pressure drop through the heat exchanger, 30 feet of piping and through the bypass piping as shown in Figure 10.

Any deviations from the arrangement shown may reduce flow, hinder performance, and will void the warranty.

2½ inch NPT piping is shown, however, models 500I-1430I and models 500E-1010E may be installed using 2 inch NPT piping.

All models must be installed in the primarysecondary arrangement shown. The boiler loop piping must tee into the filter loop piping with the inlet and outlet connection spaced a maximum of 18" (450mm) apart (see Figure 10).

To insure that pool inlet water does not exceed 104°F, the filter pump loop must circulate at the minimum flow rates shown in Table 4.

The outlet valve “A” and the bypass valve “B” must have a provision for locking the handles in place (or removing them) after the temperature rise and inlet temperature adjustments have been made.

Boiler Model Minimum Filter Pump Flow Rate

500-850 90 GPM

1010-1200 110 GPM

1430 140 GPM

1670-1825 180 GPM

Table 4. Minimum Flow to Supply Heater Loop.

Page 10

Figure 10. Heater Piping Arrangement.

Pentair Water Commercial Pool and Spa

2.8 Temperature Sensor Placement and Installation

A temperature sensor with 15 feet (5m) of cable

and an immersion well assembly are supplied with the boiler. These must be installed in the field. Refer to Figures 10 through 11.

1. The immersion well body is provided with a 1/2" NPT. Mount the immersion well on the underside of the filter circulation piping, just upstream of the boiler inlet tee as close to the boiler as possible (see Figure 10). DO NOT

INSTALL in boiler loop piping or downstream of the boiler inlet tee.

2. Thread the spring and retainer onto the sensor cable and secure sensor into the immersion well.

3. Route cable to heater control panel in a location where it will not be subject to damage. Secure with nylon cable ties.

2.9 Automatic Chlorinators

A concentration of chlorine in the heater can be

very destructive, therefore the following rules about the installation and operation of such devices must be followed:

1. The chlorinator should be installed so it introduces the gas or solution downstream from the boiler.

2. The chlorinator should be wired so it cannot operate unless the filter pump is running.

3. The chlorinator should be provided with an antisiphon device so that the draining of the piping after the pump shuts off will not siphon chlorine solution into the boiler.

4. When the operation of a chlorinator is such that it must be installed in the pump suction, or some other place where the chlorine solution flows through the heater, corrosion of the heater can occur. Excessive concentrations of chlorine caused by improper adjustment or failure of the chlorination equipment cause this corrosion. The resulting damage to the heat exchanger is not covered by heater warranty.

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