INSTALLATION & MAINTENANCE MANUAL FOR
QuickDrawâ
SEMI-INSTANTANEOUS
ENERGY: STEAM TO WATER
U-TUBE SINGLE-WALL & DOUBLE-WALL HEAT EXCHANGERS
FLOOR |
FLOOR |
DRAIN |
DRAIN |
Typical Construction
Figure 34-1
1. |
U-tube Heat Exchanger |
10. |
Potable Water Inlet |
2. |
Steam Inlet ** |
11. |
Check Valve ** |
3. |
Shutoff Valve ** |
12. |
Intratank Circulator * |
4. |
Y-Strainer * |
13. |
Potable Water Outlet |
5. |
Steam Pressure Gauge * |
14. |
Tank Drain Valve |
6. |
Steam Valve |
15. |
Relief Valve |
7. |
Condensate Drain ** |
16. |
Control Enclosure |
8. |
Main Steam Trap * |
|
* Optional |
9. |
Thermostatic Trap |
|
** Not supplied by PVI |
|
|
|
(shown with dashed lines) |
CAUTION: TEMPERATURES HIGHER THAN 125°F. INCREASE THE RISK OF SCALD INJURY!
IMPORTANT: Clearances for servicing and inspection are 18" at top, sides and rear and a minimum of one tank diameter in front.
PVI Industries, LLC ∙ |
P.O. Box 7124 ∙ Fort Worth, TX 76111 |
|
(800) 433-5654 ∙ |
www.pvi.com |
|
PV500-34 05/03 |
1 |
Section 34 |
QuickDrawâ
STEAM WITH SINGLE-WALL / DOUBLE-WALL
WARNING! Setting the temperature selector to higher settings provides hotter water which increases the risk of scald injury. Households with small children or invalids may require a
125°F or lower temperature setting to reduce the risk of scald injury. Allow a few days of operation at your selected setting to determine the correct temperature setting consistent with your needs.
CONNECTING UNIT
CAUTION
All steam and water supply lines should be flushed before connecting the unit.
1.Use backup wrenches on all screwed pipe connections to prevent damage to brazed
joints or studded connections. Shutoff valves and dielectric unions should be installed in steam and water lines to allow maintenance on the unit. Steam supply, water supply and condensate lines must be supported before connecting the unit.
ELECTRICAL
The heater is wired for 120 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, 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. Damage resulting from use of aluminum wiring will be excluded from coverage under the warranty of this unit.
PV500-34 05/03 |
2 |
Section 34 |
QuickDrawâ
STEAM WITH SINGLE-WALL / DOUBLE-WALL (con't)
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 operated 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 valve fails to flow water or reseat, consult the 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. The steam trap must have a pressure rating equal or more than the maximum steam pressure supplied to the water heater. The trap must also be sized according to the steam flow shown on the heater decal.
2.Connect the steam supply to the steam inlet fitting on the unit as shown in Figure 34-1. A Y-strainer (100 mesh recommended) must be installed ahead of and near 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 Y-strainer 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.
3.Connect condensate trap inlet at 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 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.
4.On the Quickdraw semi-instantaneous steam heater, the 3/4" thermostatic trap must be plumbed in parallel with the main steam trap for optimal operation of the heater. It speeds the removal of air from the heat exchanger when the steam valve opens. It also serves the second purpose of a vacuum breaker to protect the heat exchanger and allow proper drainage of condensate. (See Figure 34-1.)
5.Locate the thermostatic trap in a tee six inches above the main condensate line between the heat exchanger and the main trap. Plumb its outlet to a point downstream of the main trap.
PV500-34 05/03 |
3 |
Section 34 |
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