INSTALLATION AND OPERATION INSTRUCTIONS
4-2
TANKLESS WATER HEATER 199
4.1.6 Heat Exchanger
During annual inspection (with the heat exchanger cover removed), examine
the heat exchanger for signs of contamination and clean if necessary. In areas
of poor gas quality or contaminated combustion air, there may be a build-up of
black plaque (typically sulfur). Other fouling agents are airborne dust, debris and
volatiles. Clean the heat exchanger surface with a stiff plastic bristle brush only.
During maintenance, the heat exchanger gasket must be replaced. Inspect other
gaskets, and change when needed.
Refer to the heat exchanger cover removal
instructions in Section 3.4.1
for access to the combustion chamber and heat
exchanger.
Observe the safety warning regarding the burner refractory on
this page.
4.1.7 Gas Piping
Check for damage or leaks, and repair as needed.
4.1.8 Control Module
•
Check that unit operation is consistent with the steps in
Section 2.5
Sequence of Operation
.
•
Check that water temperature target is satisfactory, and that it has not been
adversely adjusted.
4.1.9 Freeze Protection
The controller ignites the burner as needed to protect the unit from freezing.
The controller ignites the burner as needed to protect the unit from freezing.
4.1.10 Relief Valve - Maintenance and Testing
Relief valve manufacturers require that under normal operating conditions a “try
lever test” must be performed quarterly. Under severe service conditions, or if
corrosion and/or deposits are noticed within the valve body, you must test more
often. Also perform a “try lever test” at the end of any non-service period.
Test at or near maximum operating pressure by holding the test lever fully open
for at least 5 seconds to flush the valve seat free of sediment and debris. Then
release the lever and permit the valve to snap shut.
If the lever does not activate, or there is no evidence of discharge, discontinue
use of equipment immediately, and contact a licensed contractor or qualified
service personnel.
If the relief valve does not completely seal, and fluid continues to leak from
the discharge pipe, perform the test again to try and flush any debris that may
be lodged in the valve. If repeated attempts fail to stop the leakage, contact a
licensed contractor or qualified service personnel to replace the valve.
4.1.11 Domestic Hot Water System
Check that the domestic hot water generation is performing as expected. Fouling
of the interior of the domestic heating coil can cause poor performance. Clean
domestic heating coil with nontoxic tankless water heater solution as required.
Quality of the domestic cold water is very important to the longevity of the unit.
CAUTION
The heat exchanger has a small
amount of combustion chamber
insulation (refractory) that
contains ceramic fibers.
When exposed to extremely
high temperatures, the ceramic
fibers, which contain crystalline
silica, can be converted into
cristobalite, classified as a
possible human carcinogen.
Avoid disturbing or damaging
the refractory. If damage occurs,
contact the factory for directions.
Avoid breathing in fumes and
contact with skin and eyes.
Follow these precautions:
1.
For conditions of frequent
use or heavy exposure,
you need a respirator. For
respirators certified by
NIOSH, refer to the “NIOSH
Guide to the Selection
and Use of Particulate
Respirators Certified under
42 CFR 84”.
For current information,
contact NIOSH on 1-800-356-
4676 or on the web at
www.cdc.gov/niosh.
2.
Wear long sleeved, loose
fitting clothing, gloves and
eyes protection.
3.
Assure adequate ventilation.
4.
Wash with soap and water
after contact.
5.
Wash potentially
contaminated clothes
separately from other
laundry, and rinse clothes
thoroughly.
6.
Discard used insulation in an
air tight plastic bag.
NIOSH first aid guidelines:
•
Eye contact - Irrigate and
wash immediately.
•
Breathing in fumes - Provide
fresh air.