Bradford White RC2PV50H6N Service manual

Condensing PV Series

Through-The-Wall Gas Water Heaters

SERVICE

MANUAL

Troubleshooting Guide

and Instructions for Service

(To be performed ONLY by

qualified service providers)

Models Covered

by This Manual:

Through‐The‐Wall Models: RC2PV50H*(N,X) LC2PV50H76*(N,X) (*) Denotes Warranty Years

Manual 238‐51526‐00B 08/18

Save this manual for future reference

The Bradford White

Condensing PV Series

Through-The-Wall Gas Water Heaters

Table of Contents

Page PV Service Procedure

Introduction ................................................................................................................................4 ---

How to Use This Manual..........................................................................................................5 ---

Tools Required for Service .......................................................................................................5 ---

Specifications .............................................................................................................................6 ---

Glossary of Terms .....................................................................................................................6 ---

Vent Tables ................................................................................................................................7 ---

Control Timings.........................................................................................................................9 ---

Sequence of Operation ..............................................................................................................10 ---

Troubleshooting.........................................................................................................................14 ---

Burner Inspection, Cleaning & Replacement .........................................................................16 I

Pilot Inspection Testing, Cleaning & Replacement................................................................ 18 II

Pressure Switch Testing & Replacement ................................................................................19 III

Blower Testing & Replacement...............................................................................................21 IV

Blower Temperature Switch Testing & Replacement ........................................................... 23 V

Gas Control Testing & Replacement.......................................................................................25 VI

Simulated Resistive Device Testing ........................................................................................29 VII

Safety Circuit Voltage Trace ....................................................................................................30 VIII

115 VAC Circuit Trace.............................................................................................................31 IX

Diptube Inspection & Replacement.........................................................................................32 X

Anode Inspection & Replacement...........................................................................................33 XI

Flue Baffle Inspection & Replacement....................................................................................34 XII

Inner Door/Gasket Removal, Inspection & Replacement .....................................................36 XIII

Condensate Trap Removal, Inspection & Replacement........................................................39 XIV

Exhaust Collector Removal, Inspection & Replacement.......................................................40 XV

Parts List ..................................................................................................................................... 42 ---

Notes ...........................................................................................................................................43 ---

Condensing PV Series

WARNING:

If the information in these instructions is not followed exactly, a fire or explosion may result causing property damage, personal injury, or death.

FOR YOUR SAFETY

Do not store or use gasoline or other flammable,

combustible, or corrosive vapors and liquids in the vicinity of this or any other appliance.

WHAT TO DO IF YOU SMELL GAS!

x Do not try to light any appliance. x Do not touch any electrical switch; do not use any

phone in your building.

x Immediately call your gas supplier from a neighbor's phone.

Follow the gas supplier's instructions.

x If you cannot reach your gas supplier, call the fire

department.

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

WARNING

Water heaters are heat producing appliances. To avoid damage or injury, do not store materials against the water heater or vent-

air intake system. Use proper care to avoid unnecessary contact

(especially by children) with the water heater and vent-air intake

components. UNDER NO CIRCUMSTANCES MUST

FLAMMABLE MATERIALS, SUCH AS GASOLINE OR PAINT

THINNER BE USED OR STORED IN THE VICINITY OF THIS

WATER HEATER, VENT-AIR INTAKE SYSTEM OR IN ANY

LOCATION FROM WHICH FUMES COULD REACH THE

WATER HEATER OR VENT-AIR INTAKE SYSTEM

CAUTION

If sweat fittings are to be used DO NOT apply heat to the nipples

on top of the water heater. Sweat the tubing to the adapter

before fitting the adapter to the water connections. It is

imperative that heat is not applied to the nipples containing a

plastic liner.

DANGER

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

IMPORTANT

Before proceeding, please inspect the

water heater and its components for

possible damage. DO NOT install any

water heater with damaged

components. If damage is evident then please contact the supplier where the water heater was purchased or the

manufacturer listed on the rating plate

for replacement parts.

WARNING

DO NOT ATTEMPT TO LIGHT ANY GAS APPLIANCE IF YOU ARE NOT CERTAIN OF THE FOLLOWING:

x Liquefied petroleum gases/propane gas and natural gas

have an odorant added by the gas supplier that aids in the detection of the gas.

x Most people recognize this odor as a “sulfur” or “rotten egg”

smell.

x Other conditions, such as “odorant fade” can cause the

odorant to diminish in intensity, or “fade”, and not be as readily detectable.

x If you have a diminished sense of smell, or are in any way

unsure of the presence of gas, immediately contact your gas supplier from a neighbor’s telephone.

Gas detectors are available. Contact your gas supplier, or plumbing professional, for more information.

WARNING

Hydrogen gas can be produced in an operating water heater that

has not had water drawn from the tank for a long period of time

(generally two weeks or more). Hydrogen gas is extremely

flammable. To prevent the possibility of injury under these

conditions, we recommend the hot water faucet to be open for

several minutes at the kitchen sink before you use any electrical

appliance which is connected to the hot water system. If hydrogen is present, there will be an unusual sound such as air escaping through the pipes as hot water begins to flow. Do not

smoke or have open flame near the faucet at the time it is open.

WARNING

FAILURE TO INSTALL AND MAINTAIN A NEW, LISTED ¾” X ¾”

TEMPERATURE AND PRESSURE RELIEF VALVE WILL RELEASE

THE MANUFACTURER FROM ANY CLAIM THAT MIGHT RESULT

FROM EXCESSIVE TEMPERATURE AND PRESSURES.

CAUTION

Turn off or disconnect the electrical power supply to the water heater before servicing. Label all wires prior to disconnection when servicing controls. Wiring errors can cause improper and dangerous operation. Verify proper operation after servicing.

Condensing PV Series

The new Bradford White residential condensing water heaters are designed to provide reliable performance with enhanced standard features. New design features include reliable spark to pilot ignition system, enhanced diagnostics, simplified servicing, significantly quiet operation and additional vent lengths.

Spark to Pilot Ignition System - employing the spark to pilot ignition system promotes reliable and consistent pilot and main burner ignitions to provide hot water on demand.

Integrated Immersion Thermostat/Gas Control Valve with LED - was developed for ease of troubleshooting by providing simple diagnostic codes to pinpoint an installation or component performance issue.

New Powerful Blower - will eliminate problems with difficult venting situations.

Quieter and Cooler Blower Operation - blower noise is significantly reduced for both interior and exterior environments. Cooler operation increases blower life by reducing bearing wear and noise.

Rugged Wiring Connections - receptacle type connections promote error free wiring.

Increased Vent Lengths - increased venting performance is achieved while achieving 90% Thermal Efficiency and enhanced Standby Loss performance.

The residential condensing water heaters use a combustion system where the flue gases are pulled at a low temperature from the water heater directly into the blower. The flue gases are evacuated to the exterior through low temperature vent materials. The gas control maintains water temperature, ignition sequence and regulates gas flow. A safety circuit consisting of a pressure switch and blower temperature switch verifies proper conditions exist for safe and reliable operation. If a situation outside of normal operating parameters exists, the gas control diagnostic LED will flash a code to positively identify an operational issue.

Introduction

This service manual is designed to facilitate problem diagnosis and enhance service efficiency.

Please read the service manual completely before attempting service on this new series of condensing power vent models.

How to Use This Manual

Condensing PV Series

It is intended for this manual to be used by qualified service personnel for the primary purpose of troubleshooting and repair of the Bradford White Condensing PV Series water heaters. Understanding the sequence of operation section of this manual will contribute greatly to troubleshooting the water heater.

The Honeywell WV4462A Electronic Gas Control will display error codes in the event of abnormal operation. Error codes are listed in the troubleshooting chart of this service manual. The troubleshooting chart will also indicate the probable cause for the error code and direct the service professional to a service procedure to properly diagnose the abnormal operation.

In some difficult to diagnose conditions, it may be necessary to isolate the heater from the vent system to determine the problem.

Contact the Bradford White technical support group immediately if diagnosis cannot be made using the methods described in this service manual.

Tools Required for Service

Manometer:

Multi-Meter:

Electronic Probes:

A liquid “U” tube type or a digital (magnahelic) type can be used. This device is used to measure gas and/or air pressure and vacuum.

A digital type is strongly recommended. This device is used to measure electrical values. The meter you select must have the capability to measure volts AC, volts DC, Amps, micro-amps and ohms.

In some cases, standard multi-meter probes will damage or simply not be effective to obtain certain voltage and ohm readings. It will be necessary to have special electronic “pin” type multi-meter probes. These probes are available at most electronic wholesale outlets.

Thermometer:

Water Pressure Gage:

Various Hand Tools:

Used to measure water temperature. An accurate thermometer is recommended.

Used to measure water supply pressure. Also used to determine tank pressure by adapting to the drain valve of the heater.

Pipe wrench, channel locks, open end wrenches (3/8”, 7/16”, 1/2”), 12” crescent wrench, allen wrench set, screw drivers (common & Phillip’s), 1/4” & 5/16” nut driver, pliers (common & needle nose), socket set, side cutters, wire cutters, wire strippers, wire crimpers, torpedo level, small shop vac, step ladder, flashlight and 5-gallon pail.

Specifications

Condensing PV Series

Power supply Dedicated 115 VAC, 60 Hz, 15A. Gas Supply Pipe Minimum 1/2” NPT (schedule 40 black iron pipe recommended). Approved Gas Type

Gas Pressure

Venting System Power vent through the wall or vertical through the roof. Approved Vent Materials Minimum Clearance for Servicing Water Supply Pressure Gas Control ECO Limit Residential Temperature Set Point Range

Commercial Temperature Set Point Range

Blower Temperature Switch

Pressure Switch

Natural Gas or Propane, unit must match gas type supplied.

5.0” w.c. min. for Natural Gas, 11.0” w.c. min. for Propane, 14.0” w.c. maximum (Natural Gas & Propane).

PVC, CPVC or ABS.

18” from top, 24” from front, 4” sides and rear.

150 psi maximum allowable working pressure. Check local codes for supply pressure.

Residential 188°F (87°C), Commercial 199°F (93°C).

60°F (16°C) to 160°F (71°C) (approximate temperatures).

80°F (27°C) to 180°F (82°C) (approximate temperatures).

Normally closed, opens @ 155°F (68°C), auto reset @ approximately 135°F (57°C).

Normally open Closes on vacuum increase @ -1.73” w.c.

Blower

115 VAC, 60 Hz, 3.3 amps, 3000 RPM @ 1.5” w.c.

Glossary of Terms

BTU British Thermal Units GPM Gallons per Minute Hz Hertz kWhr Kilowatt Hour LED Light Emitting Diode NPT National Pipe Thread Ohms Ohms of resistance psi Pounds per Square Inch RPM Revolutions per minute ECO Energy Cut Out VAC Volts Alternating Current “w.c. Inches of Water Column ºC Degrees Centigrade ºF Degrees Fahrenheit

Vent Tables

Condensing PV Series

2" Diameter (5.1 cm) Vent Connector Lengths

Terminating

Through the W all

Through the Roof

3" Diameter (10.2 cm) Vent Connector Lengths

Terminating

Vent Tables

# of

Elbows

# of

Elbows

Maximum Straight

Minimum Straight

Length ft. (m)

45 (13.7) 2 (.6)

40 (12.2)

35 (10.7) 2 (.6)

30 (9.2) 2 (.6)

50 (15.2) 7 (2.1)

45 (13.7)

40 (12.2) 7 (2.1)

35 (10.7) 7 (2.1)

30 (9.2) 7 (2.1)

Length ft. (m)

7 (2.1)

Minimum Straight

Length ft. (m)

2 (.6)

Through the W all

Through the Roof

115 (35.0) 10 (3.1)

110 (33.5) 10 (3.1)

105 (32.0) 10 (3.1)

100 (30.5) 10 (3.1)

95 (29.0) 10 (3.1)

120 (36.6) 15 (4.6)

115 (35.0) 15 (4.6)

110 (33.5) 15 (4.6)

105 (32.0) 15 (4.6)

100 (30.5) 15 (4.6)

Vent Tables

Condensing PV Series

4" Diameter (10.2 cm) Vent Connector Lengths

Terminating

Through the W all

Through the Roof

Vent Tables

# of

Elbows

Maximum Straight

Length ft. (m)

180 (54.9) 10 (3.1)

175 (53.3) 10 (3.1)

170 (51.8) 10 (3.1)

165 (50.3) 10 (3.1)

160 (48.8) 10 (3.1)

180 (54.9) 15 (4.6)

175 (53.3) 15 (4.6)

170 (51.8) 15 (4.6)

165 (50.3) 15 (4.6)

160 (48.8) 15 (4.6)

Minimum Straight

Length ft. (m)

Control Timings

Condensing PV Series

Control Timings

Ignition State Timing

Pre-purge Trial for Ignition 90 Seconds

Flame Stabilization Period Inter-purge Flame Failure Response Time 1.5 Seconds (2 second maximum; 1 second minimum.)

Post-purge 15 Seconds PS Fault Delay (failed open/close) Retry after 2 minutes Soft Lockout Retry after 5 minutes ECO Limit Lockout Indefinite (see PV SERVICE PROCEDURE VI; page 26) Verify Resistive Delay Retry after 2 minutes (repeats 5 times) Simulated Resistive Load Lockout Indefinite (cycle power to restart) Hardware Error Lockout Indefinite (self clears if fault clears for at least 15 seconds)

2 Seconds

3 Seconds 15 Seconds

Condensing PV Series

Power Up Sequence

1. Start Up. Upon power up, the control runs a safe-start check with a typical start-up delay of 5 seconds.

2. Flammable Vapor. To assure no outputs are energized if the “Simulated Resistive Device” is out of range, the control will test the “Simulated Resistive Device” for proper operating range. If “Simulated Resistive Device” is out of range, the control LED immediately flashes 7 times with a 3 second pause.

Normal Heating Sequence

1. Thermostat calls for heat. Prior to energizing the blower, the gas control checks the safety circuit to ensure that the circuit is open. Normal switch positions in the safety circuit are as follows:

Sequence of Operation

a) Pressure switch normally open. b) Blower temperature switch normally closed.

If the safety circuit is closed, the control waits 4 seconds, then the gas control LED flashes 2 times with a 3 second pause. The gas control waits 2 minutes and then the blower runs for 30 seconds. This cycle repeats until the safety circuit opens.

2. Blower energizes.

3. Pressure switch proves blower/vent system operation. If the pressure switch does not close within 30 seconds, the control LED flashes 3 times with 3 second pause. The blower runs for 30 seconds every 2 minutes trying to get the pressure switch or blower temperature switch to close. This cycle repeats as long as there is a call for heat.

4. Blower pre-purge period (2 seconds).

5. Trial for pilot ignition (90 seconds).

a. The gas control lights the pilot by activating the spark igniter and gas flow to

the pilot burner.

b. If the flame is not sensed within 90 seconds, the igniter and gas flow are

deactivated, the blower will post purge and the control LED flashes 6 times with a 3 second pause.

6. Main burner ignition. After the pilot flame is sensed, the gas control activates the main valve for main burner ignition. The gas control will ignore the flame and pressure switch signals for 3 seconds allowing for the main burner to stabilize.

Condensing PV Series

Normal Heating Sequence (cont.)

7. Steady state operation. During steady state operation, the control monitors:

Thermostat temperature sensor-when the set point temperature is satisfied, the gas valve is shut down and the blower will post purge for 15 seconds. The control LED flashes a short flash once every 4 seconds (idle) status code.

Pressure switch / blower temperature switch-if either switch opens, the pilot valve and the main valve are both shut down. The blower continues to run for 30 seconds attempting to close the circuit. The control LED flashes 3 times with a 3 second pause.

Flame sensor-if flame is lost, the pilot & main valves are shut down and the blower runs for 15 seconds. The control attempts to re-light the pilot 4 times. If unsuccessful, the blower is shut down and the control proceeds to a 5 minute lockout. The control re-attempts to light pilot starting at normal heating sequence #2.

8. Thermostat satisfies. (Control LED flashing once every 4 seconds).

9. Burner off.

10. Blower post purges (15 seconds).

Abnormal Operation

1. Simulated Resistive Device Fault:

a. If the resistance is greater than 70,000 Ohms-the gas control immediately

turns off all outputs. The control waits and monitors the resistance for 30 seconds. If the resistance is greater than 65,000 ohms after 30 seconds, the gas control proceeds to verify resistive delay for 2 minutes and flashes 7 times, then once with a three second pause. This process is repeated 5 times until the control either returns to normal operation or proceeds to flammable vapor lockout.

b. If the resistance is below 3000 Ohms-The gas control immediately turns

off all outputs and proceeds to flash 8 times, then once with a three second pause. The error self clears if the resistance returns to normal range for at least 15 seconds.

2. Temperature Sensor Fault:

a. Temperature sensor detected open circuit–The gas control immediately

turns off all outputs and proceeds to flash 8 times, then 3 times with a 3 second pause. The error self clears if the fault clears for at least 15 seconds.

b. Thermal well sensor not reading the same temperature within ±5.5°F –

The gas control immediately turns off all outputs and proceeds to flash 8



11

Sequence of Operation

Condensing PV Series

Abnormal Operation (cont.)

times, then 3 times twice with 3 second pauses. The error self clears if the fault clears for at least 15 seconds.

c. Water temperature in excess of ECO (Energy Cut Out) limit -The gas

control immediately turns off the pilot & main valves and proceeds to flash 4 times with a 3 second pause. The blower continues to run until the gas control is reset. To reset the control, rotate the temperature control knob to the minimum setting for at least 6 seconds before returning to the desired temperature setting.

3. Pressure Switch/Blower Temperature Fault:

a. Pressure switch closed at start of call for heat-the gas control waits 4

seconds, then proceeds to flash 2 times a with 3 second pause. The control waits 2 minutes and then turns on the blower for 30 seconds. The blower turns off after 30 seconds and the control waits for the pressure switch to open. Any time the pressure switch opens, the blower turns on (or stays on) and the control proceeds to wait for the pressure switch to close.

b. Pressure switch or blower temperature switch failed to close-the gas

control runs the blower for 30 seconds waiting for the pressure switch and/or blower temperature switch to close. If either switch does not close in 30 seconds, the blower turns off and the control flashes 3 times with a 3 second pause. The gas control waits 2 minutes before turning on the blower for another 30 seconds to check if the circuit will close. This cycle repeats as long as there is a call for heat or until the circuit closes.

c. Pressure switch or blower temperature switch opens during burner

operation-the gas control turns off the pilot and main valve and runs the blower for 15 seconds (inter-purge), waiting for the pressure switch and/or blower temperature switch to close. If either switch fails to close, the control proceeds as described in 3b above. If the circuit closes again by the end of the inter-purge, the recycle counter is incremented, if the recycle count has not reached its limit (4), another trial for ignition begins. If the recycle count has been reached, the gas control turns off the blower and flashes 6 times, then 2 times with a 3 second pause. The gas control waits 5 minutes before repeating ignition sequence.

4. Trial for Ignition Fault:

a. Pressure switch opens during trial-the gas control turns off the igniter and

pilot valve. The gas control proceeds as described in 3b above. If the pressure switch closes within 30 seconds, the gas control will continue with trial for ignition starting at blower pre-purge.

b. Flame not sensed-the gas control energizes the spark igniter attempting to

light the pilot and prove flame. If the flame is not sensed within 90 seconds, the igniter turns off, the pilot valve is closed and the gas control runs the

Sequence of Operation

Condensing PV Series

Abnormal Operation (cont.)

blower through post purge and flashes 6 times, then, a one time 3 second pause. The control waits 5 minutes before repeating the ignition sequence.

5. Flame sensing fault:

a. Flame lost during run-the gas control turns off the pilot and main valves

and runs blower for 15 seconds (inter-purge). The gas control increments the recycle count. If the recycle count has not reached its limit (4), another trial for ignition begins. If the recycle count limit has been reached, the gas control turns off the blower and flashes 6 times, then 3 times with a 3 second pause. The gas control waits 5 minutes before repeating the ignition sequence.

b. Flame sensed out of sequence-the gas control only looks for pilot flame

when the blower is running. If the flame is present when the pilot valve is not open, the gas control proceeds to wait for flame loss and flashes 5 times with a 3 second pause. This continues until flame signal is lost. Once the flame signal is lost, the control flashes 6 times, then 4 times with a 3 second pause. The control waits 5 minutes before repeating the ignition sequence.

Troubleshooting

Condensing PV Series

Observe green LED indicator on electronic gas control. Error flash codes are displayed with a three second pause before repeating. Check and repair the system as noted in the troubleshooting table below.

LED Status Control Status Probable Cause

None, control LED not on or flashing

Short flash once every four seconds

“Heartbeat” alternates bright/dim

Short flash once per second

Two flash, three second pause

Three flash, three second pause

Four flash, three second pause

Five flash, three second pause

No electrical Power.

Stand-by mode, waiting for call for

heat (no fault). Thermostat

calling for heat (no fault).

Weak pilot signal on last call for heat.

Pressure switch not workingclosed position.

Pressure switch or blower temp. switch not working -open position.

Excessive tank temperature. System must be

reset. Undesired-false pilot flame present.

Control power switch in “OFF” position. Supply voltage interrupted.

Temperature demand is satisfied.

Tank temperature below set point of thermostat.

1. Unstable pilot.

2. Pilot tube blocked or restricted.

3. Oxidation build up on pilot electrode.

4. Wire damage to pilot assembly or bad connection at gas valve.

5. Low gas pressure.

1. Pressure switch tubing kinked or blocked.

2. Blocked pressure tap on switch or blower.

3. Faulty pressure switch.

1. Vent blockage or improper vent

configuration.

2. Pressure switch tubing kinked or blocked.

3. Faulty pressure switch.

4. Blower not spinning up to speed.

5. Blower temp or exhaust temp too high.

6. Faulty blower temperature switch.

1. Temperature sensor out of calibration.

2. Faulty gas control.

3. Plumbing leak.

1. Pilot valve stuck in open position.

Service Procedure

Turn power on

Normal operation. Adjust thermostat to

temperature level. Normal operation. Adjust thermostat to

temperature level.

Page 18 Procedure II

Page 19 Procedure III

1. Check vent or vent tables.

2. & 3. Page 19

4. Page 21

5. & 6. Page 23

1. Page 23

2. Replace gas control, page 27

Replace gas control, page 27

+ 30 hidden pages

Bradford White RC2PV50H6N Service manual

Specifications and Main Features

Frequently Asked Questions

User Manual