HTP 399M - Manual (Page 68)

68
Resistance Tables
PART 15 – MAINTENANCE
A. MAINTENANCE PROCEDURES
Periodic maintenance should be performed once a year by a qualified service technician to assure that all the equipment is in safe
efficient operation. The owner can make necessary arrangements with a qualified heating contractor for periodic maintenance of the
boiler. Installer must also inform the owner that the lack of proper care and maintenance of the boiler may result in a hazardous
condition. The installer should discuss the contents of the User's Information Manual with the owner.
BEFORE EACH HEATING SEASON a trained and qualified service technician should perform the inspections and maintenance
procedures as identified in this manual. In addition, the maintenance and care of the boiler outlined in this manual must be performed to
assure maximum efficiency and reliability. Failure to do so could result in substantial property damage, serious personal injury, or
death.
The combustion chamber insulation in this product contains ceramic fiber material. Ceramic fibers can be converted to cristobalite in
very high temperature applications. The International Agency for Research on Cancer (IARC) has concluded, “Crystalline silica inhaled
in the form of quartz or cristobalite from occupational sources is carcinogenic to humans (Group 1).
”

Avoid breathing dust and contact with skin and eyes.

Use NIOSH certified dust respirator (N95). This type of respirator is based on the OSHA requirements for cristobalite at the
time this document was written. Other types of respirators may be needed depending on job site conditions. Current NIOSH
recommendations can be found on the NIOSH website at http://www.cdc.gov/niosh/homepage.html. NIOSH approved
respirators, manufacturers, and phone numbers are also listed on this website.

Wear long-sleeved, loose fitting clothing, gloves, and eye protection.

Apply enough water to the combustion chamber to prevent dust.

Wash potentially contaminated clothes separately from other clothing. Rinse clothes washer thoroughly.
NIOSH stated First Aid.

Eye: Irrigate immediately.

Breathing: Fresh Air.
B. MAINTENANCE SCHEDULE FOR THE SERVICE TECHNICIAN
The following maintenance should be performed annually by a qualified service technician:
General

Attend to any reported problems.
BOILER SENSOR (7250P-059) INDIRECT SENSOR (7250P-325)
NOTE: If receiving an F09 fault
code, check the gap spacing by
holding two quarters together and
sliding them through the gap. There
should be a slight resistance.
BOILER AND INDIRECT
TEMPERATURE ( o F)
RESISTANCE (ohms)
32 32550
41 25340
50 19870
59 15700
68 12490
77 10000
86 8059
95 6535
104 5330
113 4372
122 3605
131 2989
140 2490
149 2084
158 1753
167 1481
176 1256
185 1070
194 915
203 786
212 667
OUTDOOR SENSOR
(7250P-319)
OUTSIDE TEMP.
( o F)
RESISTANCE
(ohms)
-22 171800
-13 129800
-4 98930
5 76020
14 58880
23 45950
32 36130
41 28600
50 22800
59 18300
68 14770
77 12000
86 9804
95 8054
104 6652
113 5522
Table 17
Table 18