Ultra Boiler Manual

Part number 550-100-440/0122
41
  
BASIC INSTALLATION
 (continued)
Figure 41 Model 399 — Throttle screw location (ONLY

calibrated combustion test instruments)
rubber grommet into the ue pipe, then insert the probe into
the rubber grommet.
You must replace the ue gas temperature sensor to
prevent ue gas spillage into the boiler enclosure.
Failure to comply could result in severe personal
injury, death or substantial property damage.
Ultra-399 propane conversion & start-up
Ultra-399 boilers are converted for propane by adjustment of the
gas valve throttle screw (no orice change) — Figure41. is must
only be done while using a combustion analyzer.
1. Turn the gas valve throttle screw clockwise 5 turns before start-
ing the boiler. en follow the start-up procedure on page40.
2. Once the boiler is started, make slight adjustments to the throttle
screw to obtain a CO
2
of 10.2% with CO less than 100 ppm air
free. (Allow the combustion analyzer’s reading to stabilize before
making adjustments.)
3. Aer the boiler has been set up correctly, the conversion is
complete. Fill in the information on the propane conversion
label and attach the label to the boiler rating plate.
Throttle screw adjustment procedure
See Figure39,page40, Figure40,page40, or Figure41 for location
of the throttle screw.
DO NOT attempt to adjust the throttle screw unless by
a qualied technician, and with the use of calibrated
combustion test instruments. Adjust the throttle
screw only as needed to meet the combustion values
given in Figure42.
1. is procedure is only necessary when specied elsewhere in
this manual or when combustion tests indicate the need, as
explained under “     
instruments, page 40.”
2. Boiler behavior that might indicate a need to check combustion
values at high re (as per page40) to verify boiler is in adjust-
ment include: diculty igniting, poor ame stability at low re,
combustion noise or high carbon monoxide values.
3. Combustion readings must be taken at both high re and low
re. DO NOT attempt an adjustment of the throttle screw at
low re. Just check the combustion values.
4. Use the U-Control display to navigate to Manual test mode
(see Figure115,page102) and force the ring rate to MAX
(high re). Aer the boiler has had time to stabilize, take a
CO
2
reading.
a. If the CO
2
is HIGH, turn the throttle screw CLOCKWISE
to lower the input. Allow the boiler to stabilize and take
another reading. Continue until the desired CO
2
value is
achieved.
b. If the CO
2
is LOW, turn the throttle screw COUNTER-
CLOCKWISE to increase the input. Allow the boiler to
stabilize and take another reading. Continue until the
desired CO
2
value is achieved.
5. Lock the boiler into low re. Check the combustion readings. If
results are acceptable at low re, verify high re readings again.
Restore ring rate to AUTO.
6. Consult your local WM Technologies representative if accept-
able results cannot be obtained for both high and low re.

1. Follow instructions in this manual to set and verify
operation of the boiler controls.
Figure 42 Acceptable CO2 and CO values (CO2 values must be
within 1.0% of the values listed)
Boiler
Ultra
Fuel
 
%CO
2
CO ppm %CO
2
CO ppm
-80
NG 8.6 < 60 7.8 < 60
LP 9.6 < 60 8.6 < 60
-105
NG 9.0 < 60 8.4 < 60
LP 10.1 < 60 9.2 < 60
-155
NG 9.0 < 60 8.0 < 60
LP 10.0 < 60 8.5 < 60
-230
NG 9.0 < 60 8.0 < 60
LP 10.0 < 60 9.0 < 60
-299
NG 9.0 < 60 8.0 < 60
LP 10.0 < 60 9.0 < 60
-399
NG 9.2 < 100 8.4 < 60
LP 10.2 < 100 10.0 < 60
The values above are with the boiler front door removed. Values will typically
increase about 0.2% once the door is reinstalled.
The values above are for altitudes up to 5,500 feet. For higher altitudes, CO
2
may be slightly lower and CO slightly higher.