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110328-02 - 6/22
ALTA
• Water Boiler
• Condensing
• Direct Vent Models
• Gas Fired
Models:
• ALTA-120
• ALTA-150
• ALTA-180
WARNING
This boiler must only be installed, serviced, or repaired by a qualified installer, service agency or gas supplier.
Improper installation, adjustment, alteration, service or maintenance can cause severe personal injury, death,
or substantial property damage. For assistance or additional information, consult a qualified installer, service
agency, or the gas supplier. Read these instructions carefully before installing.
!
Installation, Operating and Service Instructions for
Manual Contents Page
1. Installer Read Before Proceeding . . . . . . . . . . .3
2. Homeowner Read Before Proceeding . . . . . . . .4
3. Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . .4
4. How It Works . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
5. Locating Boiler . . . . . . . . . . . . . . . . . . . . . . . . . .8
6. Preparing Boiler . . . . . . . . . . . . . . . . . . . . . . . .12
7. General Venting . . . . . . . . . . . . . . . . . . . . . . . . .15
8. Sidewall Direct Venting . . . . . . . . . . . . . . . . . . .22
9. Vertical Direct Venting . . . . . . . . . . . . . . . . . . .28
10. Heating System Piping . . . . . . . . . . . . . . . . . . .34
11. Gas Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
12. Field Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
13. Condensate Disposal . . . . . . . . . . . . . . . . . . . .45
14. Start-up and Checkout . . . . . . . . . . . . . . . . . .46
15. Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
16. Before Leaving Jobsite . . . . . . . . . . . . . . . . . .65
17. Service and Maintenance . . . . . . . . . . . . . . . . .66
18. Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . .70
19. Internal Wiring Diagrams . . . . . . . . . . . . . . . . .85
20. Service Parts . . . . . . . . . . . . . . . . . . . . . . . . . . .88
Appendix
A. Combination Refrigeration/Heating System . .94
B. Water Quality and Boiler Additives . . . . . . . . .95
C. Special Requirements In Massachusetts . . . .96
D. Code Required Text . . . . . . . . . . . . . . . . . . . . . .98
TO THE INSTALLER:
Affix these instructions adjacent to boiler.
Provide model number and serial number when
seeking information and support.
TO THE HOMEOWNER:
Retain these instructions for future reference.
Contact heating installer or technician for all issues
and support.