Whirlpool EDP/EDN 10B. Short Cycling, 10C. Noisy Operation, 10D. Insufficient Hot Water EBP only

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LAARS HEATING SYSTEMS

 

 

 

 

Gas valve regulation problems can also cause delayed ignitions. See “Gas valve calibration”.

Incorrect gas orifice – Check orifice size.

A defective burner can cause a delayed ignition during operation or at shutdown. If the gas supply pressure is proper the gas valve is functioning properly and the gas orifice is correct, the burner should be inspected. To inspect it, remove the blower. The burner is retained by the blower and it will drop out of the bottom of the chamber when the blower is removed. There should be no distortion or perforations in the burner other than the punched holes. Replace if indicated.

10B. Short Cycling

Possible causes

a.Reduced system flow - EDP

b.Thermostatic union (EDP) or anti-condensing valve not opening (EBP).

c.T-T wires cross connected (jumped) – improper installation - EBP or EDP/EDN

d.Leakage of flue products into the combustion air stream – Direct Vent Installations only, see Section 8B-3, Resolving Lockouts (LO), item (5).

10C. Noisy Operation

There are two principal sources of noisy operation:

a.Combustion - high pitched noise - whistle or hoot.

b.Boiling (kettling) - lower frequency noise which varies with temperature - moan.

Many times it is difficult to determine the source of the noise or if it is combustion related or boiling related. Combustion noises always have the same frequency; however, their volume may change from the time that the burner first fires to the time that it shuts off. A boiling noise is identified by rapidly raising or lowering the system water pressure while the noise is present. A change in the pitch or intensity of the noise indicates a boiling problem.

Combustion noise occurs at any boiler discharge temperature and is heard the loudest at the flue outlet (especially on units that are sidewall vented). There are two basic causes for the noise, rich mixture (high CO2 or low O2) or cross contamination. The mixture is determined by measuring the percent O2 or CO2 in the flue products. O2 readings lower than 4½ % or CO 2 readings higher than 9¼ % (natural gas) and 10.8% (LP) will often cause combustion related noise. The rich mixture could be caused by the mis- calibration of the gas valve (offset adjustment) or by the gas orifice size. To eliminate the noise; first, check the gas valve calibration. If it is correct, install a smaller gas orifice so that the O2 will rise above 4½% or the CO2 will drop to 8½% (natural) or 9½% (LP).

The CO2 & O2 readings may be influenced by cross contamination. Suspect cross contamination if the noise returns when the front panel is replaced.

Boiling (kettling) may occur at boiler discharge temperatures from 170°F to 210°F. The temperature at which it starts will vary from one installation to another. The primary cause of the problem is poor heat transfer on the inside of the boiler coil. This may be caused by foaming due to excessive concentration of antifreeze in the system or by scaling from the boiler water due to hardness of make up water.

Plumbing antifreezes should never be used in a boiler system. Only boiler antifreezes, with effective antifoamants, are appropriate for the ENDURANCE boilers.

Note: The concentration of appropriate antifreeze should be always be kept as low as possible to minimize its effect on heat transfer and efficiency.

The method for eliminating the boiling noise is the same regardless of the cause. However, if antifreeze in the system is suspected of being the cause, the concentration (<35%) and type should be investigated.

Moisture

Although it is not a primary cause of lockouts, moisture in the combustion chamber may cause lockouts by weakening the flame signal to the boiler control. It should be suspected if the boiler temperature does not rise above 160°F during long periods of operation. This condition can be caused by a defective thermostat in the thermostatic union of EDN or EDP boilers (or the omission of the thermostatic union at installation) or failure of the anticondensing valve in the EBP (combi) boilers. Moisture can also get into the combustion chamber through an incorrectly pitched or incorrectly installed flue pipe (pitched back toward the boiler without a condensate trap). The flue assembly of EBP, EDN and EDP boilers installed as Direct Vent boilers should always pitch down from the boiler.

10D. Insufficient Hot Water (EBP only)

Possible cause:

a.No flow restrictor (supplied with unit - field installed)

b.Water flow switch failure

c.Mixing valve setting or failure

d.Domestic hot water (DHW) heat exchanger contamination

The most common cause for insufficient hot water complaints results from failure to install a flow restrictor. The absence of a flow restrictor allows water to pass through the heat exchanger at a greater rate than the boiler output is capable of heating to the desired temperature.

Failure of the water flow switch to operate during a hot water draw prevents boiler water from

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Contents Endurance Table of Contents 1B. Codes and Standards General Information1A. Introduction Venting Options Endurance Laars Heating Systems 2E. Air Source For Combustion when not direct vented For Appliances Certified as Direct Vent3A. Gas Piping 2F. Connecting Special Gas Vent to the Appliance2G. Securing Special Gas Vent 3B. Domestic Water Piping EBP only Length Capacity of PipeHydronic Heat Piping 4A. Hydronic PipingHydronic Piping EDP/EBP with Zone Valves Hydronic Piping EBP/EDP for Systems Zoned with Circulators Electrical Connections 4C. Water Quality and TreatmentMultiple Zones with Circulators and Room Thermostats For Your Safety Read Before Operating Fermeture DE L’ALIMENTATION EN GAZ 6A. Common Vent Test To read or change modeBoiler Start Up 6B. Filling the System 6C. Firing BurnerMaintenance and Component Description 7E. Ignitor / Flame Sensor Assembly 7J. Cleaning the Boiler Coil7F. Transformer 7G. BlowerServicing 8A. Sequence of Operation8B. Trouble Shooting Fault Codes 8B-1. Fault Code IdentificationPower UP Fault Tree Ignition Fault Tree Space Heating Domestic HOT Water Boiler Temperature Poor flame sensor signal The boiler control EDP/EDN Wiring Diagram EBP Wiring Diagram Symptom Evaluations 9A. Gas Valve Calibration offset adjustment10A. Delayed ignition Gas Valve Calibration10D. Insufficient Hot Water EBP only 10B. Short Cycling10C. Noisy Operation 10E. High Gas Consumption Parts Identification Model EDP/EDNModel EBP Boiler DrainBox Lynnfield, MA Phone Fax