How To Change Orifices; Equivalent Orifice Sizes At High Altitudes; Troubleshooting - HydroTherm HC-65 Installation Operation & Maintenance

HOW TO CHANGE ORIFICES

1. Shut off power supply and gas supply to the boiler.
2. Remove burner access panel. To remove burners, lift
up & to rear until burners are disengaged from orifices.
3. Check orifices for proper drill size. Size is stamped
onto the body of the brass orifice. The size can also be
checked by using a pin gauge (see Figure 3.1). All ori-
fices are screwed into the manifold and may be removed
by using a 5/8" wrench or socket.
EQUIVALENT ORIFICE SIZES AT HIGH ALTITUDES (INCLUDES 4% INPUT REDUCTION FOR EACH 1,000 FEET)
Model # Fuel Type Orifice Qty.
HC-65D,E NG
HC-65D,E LP
HC-85D,E NG
HC-85D,E LP
HC-100D,E NG
HC-100D,E LP
HC-120D NG
HC-120D LP
HC-125E NG
HC-125E LP
HC-145D,E NG
HC-145D,E LP
HC-165D,E NG
HC-165D,E LP
NOTE: For orifice part numbers, see "Orifice Part Numbers" chart on page 24.
NO HEAT
1. Blown fuse or circuit breaker.
2. Power switch turned off.
3. IID system malfunction.
4. Vent damper not open.
5. Circulator not running.
6. Air in lines and radiation.
7. Tripped rollout switch.
8. Tripped spill switch.
INSUFFICIENT HEAT
1. Incorrect t'stat anticipator setting.
2. Hi-limit control setting too low.
3. Boiler undersized or underfired.
4. Insufficient radiation.
CAUTION:
Label all wires prior to disconnection when servicing controls. Wiring errors can cause improper and dan-
gerous operation.
Verify proper operation after servicing.
Sea Level 2000 ft.
2 2.60mm 39
2 52 52
2 32 33
2 49 50
3 37 38
3 1.65mm 52
4 40 41
4 1.55mm 54
4 39 40
4 1.60mm 1.60mm
4 35 36
4 51 51
4 32 33
4 1.85mm 50

TROUBLESHOOTING

5. Air traps in lines or radiation.
OVERHEATING
1. Wrong thermostat anticipator set-
ting.
2. Bad thermostat location.
3. Bad thermostat.
ODOR, EXCESSIVE MOISTURE IN
BUILDING
1. Leak in piping.
2. Carbon build-up in flueways.
3. Blocked chimney.
4. Downdrafts- incorrect termination
MODEL
HC-65
HC-85
HC-100
HC-120
HC-145
HC-165
4. Reverse above procedures to install orifices & burn-
ers. BE SURE TO INSTALL BURNERS WITH BURNER
PORTS ON TOP SURFACE (UPRIGHT).
Orifice Size
3000 ft. 4000 ft. 5000 ft.
40 41 41
53 53 53
34 35 35
50 50 51
39 39 40
53 53 53
42 42 42
54 54 54
41 41 42
53 53 53
36 37 37
52 52 52
34 35 35
50 50 51
19
NAT. GAS
DRILL SIZE
2.60MM
32
37
40
35
32
FIGURE 3.1
6000 ft. 7000 ft. 8000 ft.
42 42 43
53 53 54
36 36 37
51 51 52
41 42 42
53 53 54
43 43 44
54 54 55
42 43 43
53 53 54
38 39 40
52 53 53
36 36 37
51 51 52
YELLOW FLAME, CARBON
BUILD-UP
1. Unit overfired.
2. Air shutter misadjustment
3. Wrong orifices.
4. Burning in burner mixing tube.
5. Inadequate combustion air.
6. Inadequate draft (flue blockage).
NOISE
1. Ignition-incorrect air shutter adjust-
ment
2. Whistle due to burr on orifices.
3. Burner "fluteing" -air shutter open-
ing too wide.
L.P. GAS
DRILL SIZE
52
49
1.65MM
1.55MM
51
1.85MM
9000 ft. 10000 ft.
43 44
54 54
38 40
52 52
43 43
54 54
44 46
55 55
44 44
54 54
41 42
53 54
38 40
52 52