PVI Industries Storage and Semi-instantaneous Steam Heaters PV500-25 User manual

PVI Industries Storage and Semi-instantaneous Steam Heaters PV500-25 User manual
INSTALLATION & MAINTENANCE MANUAL
QuickDraw® Storage and Semi-instantaneous
Steam Heaters
Installation and service must be performed by a qualified service installer, service agency or the utility supplier.
IMPORTANT: THIS MANUAL CONTAINS INFORMATION REQUIRED FOR INSTALLATION, OPERATION AND
MAINTENANCE OF THIS EQUIPMENT. READ AND FOLLOW ALL INSTRUCTIONS, LABELS AND MARKINGS
BEFORE INSTALLING, OPERATING OR SERVICING THIS UNIT.
TABLE OF CONTENTS
TOPIC
PAGE
Checking Equipment
Location and Electrical
Installation and Clearances
Typical Construction
Important Safety Notice
Water Inlet/Outlet Connections
Filling the Unit
Relief Valve Piping
Steam and Cond. Connections
Startup Procedure
Maintenance
2
2
3
4
5
6
6
6
6
7
8
TO THE INSTALLER: After installation, these instructions must be given to the equipment user or left near
the appliance.
SPECIAL INSTRUCTIONS TO THE OWNER: Retain this manual for future reference. These instructions
contain important information that will help you in maintaining and operating this appliance.
PVI INDUSTRIES, LLC - P.O. Box 7124 - Fort Worth, Texas 76111 - 1-800-433-5654
PV500-25 10/07
QUICKDRAW® Steam Heater
CHECKING EQUIPMENT BEFORE YOU INSTALL
Inspect the unit completely upon receipt from the freight carrier before signing the bill of lading. Inspect the
appliance and all accompanying parts for signs of impact or mishandling. Verify the total number of pieces
shown on packing slips with those actually received. Contact the freight carrier immediately if any damage
or shortage is detected.
WARRANTY
Factory warranty does not cover improper installation or operation. (See warranty for complete details).
Warranty exclusions include but are not limited to failure or malfunctions resulting from:
1. Failures to properly apply, install, operate, or maintain the appliance in accordance to printed
instructions.
2. Abuse, alteration, accident, fire, flood and the like.
3. Sediment or lime buildup, freezing or any other conditions causing inadequate circulation.
4. Corrosive or contaminated atmosphere.
LOCATION
1. Locate the unit in a clean and dry area as close as possible to the greatest hot water usage and as
near to boiler water and/or electrical power as practical.
2. Install the unit on a firm, level foundation.
3. Locate the foundation on a pitched floor near a suitable drain, or make other provisions to prevent
contact to areas of the building subject to water damage should the boiler or a water connection leak.
4. The drain must be sufficient to contain water in excess of 210°F.
CODES
The equipment shall be installed in accordance with the instructions in this manual, appliance markings and
supplemental instructions and in compliance with those installation regulations in force in the local area
where the installation is to be made. These shall be carefully followed in all cases. Authorities having
jurisdiction shall be consulted before installation is made. All appliances conform to the latest edition of the
ASME Boiler and Pressure Vessel Code, Section IV, Part HLW.
ELECTRICAL
The heater is wired for 120VAC/1ph/60Hz volts and must be electrically grounded in accordance with local
codes, or in the absence of local codes, with the latest edition of the National Electrical Code ANSI/NFPA.
When unit is installed in Canada, it must conform to the CSA C22.1, Canadian Electrical Code (CEC), Part
1 and/or local electrical codes.
1. Branch circuit protection and disconnecting means must be furnished by the installer. Refer to the
wiring diagram provided with this unit when installing or troubleshooting the electrical components of
this heater.
2. All wiring must be in accordance with all local, state, or federal codes
3. Provide proper overload protection for the system’s circulating pump.
Note: Use only copper wire of proper sizing for incoming service. The warranty on this unit does not
cover damage resulting from the use of aluminum wiring.
INSTALLATION
2
QUICKDRAW® Steam Heater
WARNING: Use industry standard safe rigging methods when attempting to lift or move
this product. Failure to follow these instructions could result in property damage, serious
injury or death. One common method includes the use of straps and spreader bars, lifting
from the water heater base skid assembly.
1. Check the data decal on the heater. Be sure the electrical supply is adequate for the installation.
2. Carefully remove all shipping supports and bracing.
3. Do not attempt to move or lift heater by the plumbing connections or heat exchanger. Lift only by the
skid using industry standard safe rigging methods.
4. Provide sufficient clearance in front of heat exchanger to facilitate maintenance and removal. See
“Service Clearances” below.
5. Install shut-off valves and unions on the inlet and outlet water piping for servicing. Use caution when
threading pipe nipples into tank connections to prevent cross threading, or over-tightening. Always use a
back-up wrench on tank nipples when tightening unions, valves, etc.
6. Insulate hot water and return circulation lines. Insulate cold water supply lines if subject to freezing
during shutdown periods. IMPORTANT: Do not use the plumbing connected to the appliance as a
ground for welding or any other purpose.
7. The water heater is equipped with a temperature and pressure relief valve(s) rated for the input. Pipe the
relief valve discharge to a suitable open drain. The drain pipe may not be smaller than the relief valve
opening and must be secured to prevent it from lifting out of the drain under discharge pressure. Do not
install valves or restrictions in the discharge line.
8. Pipe the drain valve to a suitable open drain.
WARNING: All system piping to the heat exchanger plumbing must be adequately
supported. Failure to do so will result in excessive loads on the heat exchanger
connections causing damage and/or leakage and potential injury to adjacent personnel.
SERVICE CLEARANCES
Allow sufficient space to provide adequate clearances on all sides for service and inspection.
Recommended clearance is 24” at the top and front, 18” at left and right sides of the appliance. Optional
equipment may increase the clearance requirements. Allow sufficient space for installing and servicing
connections such as water, electrical, pump and other auxiliary equipment.
3
QUICKDRAW® Steam Heater
Typical QuickDraw® Storage Construction
Typical QuickDraw® Instantaneous Construction
1.
2.
3.
4.
U-tube Heat Exchanger
Tank Drain
Control Enclosure
Relief Valve (AGA optional)
5. Potable Water Inlet
6. Steam Inlet
7. Potable Water Outlet
8. Condensate Outlet
Note: Components, controls and connection locations may vary.
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QUICKDRAW® Steam Heater
IMPORTANT SAFETY NOTE
It takes only 5 seconds of skin contact with 140°F water to cause a
second degree burn! You must protect against high water temperatures at all
lavatories, tubs, showers and other points of hot water contact.
Accidental scalding from high water temperatures is a greater
risk in some types of installations. Some examples are:
HOMES FOR THE MENTALLY HANDICAPPED
HOMES FOR THE PHYSICALLY HANDICAPPED
HOSPITALS AND NURSING HOMES
ELDER CARE FACILITIES AND REST HOMES
ORPHANAGES AND CHILD CARE FACILITIES
OTHER INSTALLATIONS - WHERE RESPONSE TO CONTACT WITH HOT WATER
MAY BE SLOWER OR WHERE THE DANGER OF HOT WATER CONTACT IS GREATER
Thermostatically controlled mixing valves
must be used in the design of the potable hot water system.
Potable hot water should be tempered to no more than 110°F
when used for bathing or other personal uses.
Good engineering practice mandates the use of thermostatically
controlled mixing valves set at 120°F or less to keep the delivered water
temperature below scalding temperatures.
5
QUICKDRAW® Steam Heater
WATER INLET / OUTLET CONNECTIONS
Important: Do not use galvanized or steel pipe nipples when making waterside connections. Use
non-ferrous nipples only.
Make inlet and outlet water connections directly to the threaded bolt-on bronze tank flanges. Over tightening
connections to the flanges may cause damage to the flange or tank and are not covered by warranty. For
ease of service, install unions on inlet and outlet piping to the unit. Do not use galvanized nipples to make
tank connections as these will cause corrosion and rust. Piping and components connected to the water
heater must be suitable for potable water, for the water temperatures they will experience and for their
application.
CAUTION: Flush all water supply lines before connecting the unit.
FILLING THE UNIT
1. Fill the system with water. To be sure that the unit is not “air bound,” open the relief valve. Leave the
valve open until a steady flow of water is observed. Close valve and complete filling the system.
2. In hard water areas, potable water treatment should be used to reduce introduction of minerals into the
system. Minerals in the water can collect on the tubes and heat-exchanger surfaces reducing the life of
the product. Heat exchanger failure due to scale accumulation is not covered by the product warranty.
3. Make sure there are no system leaks. DO NOT use petroleum based stop-leak products. All system
leaks must be repaired.
RELIEF VALVE PIPING
The water heater is supplied with a pressure and temperature relief valve, sized in accordance with ASME
requirements. Each relief valve should be piped to a suitable floor drain. No reducing coupling or other
restriction can be installed in the discharge line. It is strongly recommended that this valve should be
manually operating at least once a year.
WARNING: Make sure the safety relief valve is piped to a proper drain per instructions.
Scalding injury and/or water damage can occur from either the manual lifting of the lever or
the normal operation of the valve if it is not piped to a proper drain. Insure that the safety
relief valve piping is of the proper material and rating for the temperature and pressure of
the system and that it is secured to prevent possible injury. If the valve fails to flow water or
reseat, consult factory. The relief valve is a primary safety device.
STEAM & CONDENSATE CONNECTIONS
1. The condensate trap controls the discharge of condensate based on the load on the heat
exchanger, thus preventing the discharge of live steam through the unit. Appropriately sized traps
are available from your PVI representative.
2. Connect the steam supply to the steam inlet fitting on the unit. A Y-strainer (100 mesh stainless
steel sheet) must be installed ahead of the unit to prevent particles of scale and other solids from
damaging the seats of the steam valve. It is good practice to install a blowdown valve on the Ystrainer piped to a suitable location that can be opened at intervals to clean the strainer screen. A
condensate trap may be located upstream of the steam valve. This trap will drain the condensate
that collects in the piping and must be plumbed to a suitable drain or the condensate receiver
plumbing.
6
QUICKDRAW® Steam Heater
3. Connect condensate trap inlet parallel to or below the outlet of the heat exchanger. The ability to lift
condensate via steam pressure cannot be assured on QuickDraw products due to the possible use
of a modulating steam valve (storage units only) or multiple solenoid steam control system. The
recommended methods of condensate distribution are:
a. Plumb to a condensate receiver and pump or vacuum return to the condensate return header.
b. Plumb to a pneumatic/electric actuated condensate pump trap for return to the condensate
return header.
c. Drain to atmosphere – (would require constant make-up of boiler water).
Inadequate drainage of condensate can adversely affect heat transfer and limit the performance of
the water heater. Please note damage to the water heater attributed to poor condensate drainage is
not covered in the product warranty.
STEAM VALVES
Two position on-off electric valves are used. The valves will return to the closed position when power is
off. This feature will prevent an excessive temperature buildup in the event of a power failure. The valve
manufacturer’s operation and maintenance instructions ship with the unit. Refer to these instructions
during start-up and file for future referencing on maintenance.
CAUTION: Most valve problems are caused by dirt or trash in the steam line. This is most likely
to occur during installation. Teflon pipe tape, pipe joint compounds, metal particles and dirt will
clog up strainers and orifices and prevent valve seats from closing. Clean all pipe line strainers
at start-up and check the valves again after a few days operation as recommended maintenance
by the valve manufacturer. Inspection of strainers and blowdown piping should be part of the
normal maintenance routine on this equipment.
START-UP PROCEDURE
1. When placing the unit into operation, open relief valve to purge air from top of tank and begin to fill
the tank with cold water. Check for plumbing leaks. Be sure to fill the tank completely before closing
the relief valve.
CAUTION: Do not energize the heater or circulating pump until the tank is full of water. Serious
damage may result.
2. Push control switch, located on the control box, to activate the steam valve and thermostats. Check
steam valve for operation; the valve solenoid should “click” to open valves when operating switch is
pushed “on”. The tank-circulating pump should also operate. Check thermostat settings. The
temperature-limiting device is set at 200°F.
Temperature Setting: The operating thermostat is set at the factory at approximately 120°F and
the upper operating thermostat is set at approximately 130°F. Make adjustments by turning the
thermostat dial to the desired temperature.
3. Push the operating switch, located on the control box, to “off” before opening manual main steam
supply valve. This will allow condensate that has collected in the supply line to drain through the
trap installed in front of the steam valve. When the steam supply line is free of condensate, push
operating switch to “on”, opening the electric on-off steam valves allowing steam to flow through the
heat exchanger.
4. Do not operate unit under conditions in excess of those specified on nameplate.
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QUICKDRAW® Steam Heater
WARNING: Failure to operate the heat exchanger within the design pressure and
temperature on the nameplate may result in damage to the heat exchanger and potential
injury to adjacent personnel.
5. Open nearby hot water tap to maintain a flow of water through the tank when starting up units.
Regulate flow of water through the tank to allow the steam valve(s) to cycle off and on. Open
nearby hot water tap to maintain a flow of water through the tank when starting up units. Observe
condensate flow at the receiver or other collection sight to verify satisfactory flow. Check operation
of all safety and operating controls.
6. In all installations, there should be no pulsation or water hammer since this causes vibration and
strain with resulting leaks.
7. Retighten bolting on all gasketed joints after the heat exchanger has reached temperature to
prevent leaks and gasket failures. Retightening should be done uniformly and in a diametrically
staggered pattern (see “Maintenance”). On high pressure and high temperature applications or any
application where spiral wound gaskets are required, it is recommended that the gasketed joints of
the heat exchanger be retightened to the required torque (see “Maintenance”) after 24 hours at
operating pressures and temperatures to compensate for any relaxation or creep that may have
occurred.
8. In shutting down, remove all power from the system. Close all steam and cold water supply valves
to the unit.
9. If the unit is removed from service for an extended period, it must be drained to eliminate the
possibility of freezing and corrosion from stagnant water conditions.
MAINTENANCE
WARNING: To reduce the risk of electrical shock injury or death, on control systems
using 120 volt external power, be certain switch is off and power disconnected before
work is performed on this heater.
Temperature and Pressure Relief Valve
Operate the temperature and pressure relief valve at least once a year by lifting the lever briefly. If the
valve does not open and close properly when testing, it must be replaced with a like relief valve.
Thermostats and Temperature Limiting Device
The temperature limiting device and thermostat temperature sensors extend into the water in the tank.
Depending on the water conditions in your area, scale may coat the sensors. This coating will affect
accuracy of sensors and can allow water temperature to exceed the desired limits. Remove and inspect
these controls at necessary intervals. Remove scale if present.
8
QUICKDRAW® Steam Heater
Steam Valve Actuator
The steam valve actuator (if applicable) is sealed and requires no maintenance. Durability of valve
stems and packing is dependent upon maintaining non-damaging water conditions. Inadequate water
treatment or filtration can result in corrosion, scale, and abrasive particle formation. Scale and
particulates can result in stem and packing scratches and can adversely affect packing life and other
parts of the Hydronic system. Contact the manufacturer for replacement packing and stem & plug
assembly.
Tank
Scale will normally form in the tank during operation and will accumulate on the bottom of the tank. The
natural chemicals in the water forms scale which precipitate out during the heating cycles. Some water
supplies contain more of these chemicals than others do, and the scale buildup will occur more rapidly.
Other factors affecting the scale buildup are the amount of hot water used and the temperature of the
water. The more hot water used the more fresh water containing the scale-forming chemicals enter into
the tank. As the temperature of the water increases, the rate of scale deposited also increases. The
frequency of inspections will be determined by the rate of scale buildup. Until the appropriate inspection
and cleaning frequency is established, initially inspect the tank every six months or more frequently if
higher scaling conditions are present.
Flush the tank at two or three-month intervals depending on water conditions in your location to help
prevent the accumulation of scale. To flush: turn off electrical disconnect switch to prevent the unit
from operating. Open the drain valve and allow water to flow through the tank until it runs clear. Close
the drain valve and turn the electrical switch back on.
WARNING: Since PVI cannot control the use of the water heater, water conditions, or
maintenance, the warranty on the water heater does not cover poor performance,
structural failure, or leaking due to an excessive accumulation of scale.
Cleaning the Heat Exchanger (refer to figure on page 10)
1. Do not open until all pressure is removed, the unit is drained and the equipment surfaces cooled to
ambient temperature.
2. Heat exchangers subject to fouling or scaling should be cleaned periodically. A light sludge or scale
coating on the tube greatly reduces its effectiveness. A marked increase in pressure drop and/or
reduction in performance usually indicate cleaning is necessary.
3. Tube bundle removal:
a. When practical, leave tube bundle attached to collar assembly and remove by unbolting collar
assembly from tank.
b. During bundle removal, the dead weight of bundle should never be supported on individual
tubes or contact any lined interior tank surface. Following removal, rest the bundle on the tube
sheet, support plates, or wood blocks cut to fit periphery of the bundle.
c. Tube bundles may be raised using slings formed by bending light sheet metal into a “U” form
and attaching lifting lugs to the ends of the sheets. Baffles can be easily bent and damaged if
dragged over rough surfaces.
d. Before reinserting the tube bundle into the unit, place the ring/tank gasket over the end of the
tube bundle and bring forward to the backside of the tube sheet.
9
QUICKDRAW® Steam Heater
CAUTION: When cleaning a tube bundle, tubes should not be hammered on with any metallic
tool and, in case it is necessary to use scrapers, care should be exercised that the scraper is
not sharp enough to cut the metal of the tubes.
4. When replacing the heat exchanger head, use a torque wrench to tighten the bolts/studs and nuts.
Use the following chart as a guide. All torque values apply to well-lubricated nut bearing surfaces.
TIGHTENING TORQUES
Bolt
Dia.
1/2"
5/8"
Bolt/Stud
Dia.
1/2"
5/8"
3/4"
7/8"
1"
1 1/8"
1 1/4"
COMPRESSED FIBER GASKETS
Recommended
Torque
Torque
ft-lbs
Increment
40
5
80
5
Max.
Torque
60
120
SPIRAL WOUND GASKETS
Recommended
Torque
Torque
ft-lbs
Increment
40
5
80
5
120
5
200
10
300
10
450
10
600
10
Max.
Torque
60
120
200
320
490
710
1000
10
QUICKDRAW® Steam Heater
5. Tighten uniformly and in a diametrically staggered pattern as illustrated below:
WARNING: It is extremely important to follow
a proper tightening sequence. If not followed,
the flanges can become cocked and a leak
will result. When tightening flanges with
spiral wound gaskets, if cocking occurs, the
result can be deformation and non-repairable
damage to the gaskets in addition to a
resultant leak. Any gasket leak can result in
potential injury to adjacent personnel.
11
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