Raypak 88AR-398A, Installation & Operating Instructions Manual

Page: 49 / 68

49
9. Replace the Natural Gas Venturi with the Propane
Venturi (see Fig 52).
10. Re-install (3) screws to secure the Propane
Venturi to Blower.
11. Re-install Gas Valve assembly to Venturi by secur-
ing the union between them.
12. Tighten union to secure supply line to Gas valve.
13. Turn manual valve back on.
14. See “Gas Valve Adjustment” before running boiler.
GAS VALVE ADJUSTMENT
A Gas Valve adjustment is required to attain optimal
performance from the boiler when replacing one or
converting gas. These instructions must be followed
by a trained qualified technician or manufacturing
representative.
Valve adjustment throttle locations are indicated on
Figure 53.
Setting Hi Fire Throttle:
1. Turn the needle down (clockwise) until the needle
bottoms out.
2. Follow Table U below for the number of 360°
counter-clockwise turns needed for each model
and Gas Type.
3. Once adjustment is made, turn heater on.
4. Adjust 0-10 VDC SIGNAL to 10 VDC.
5. Wait until “FIRE RATE” reaches 100%.
6. Adjust Hi Fire Throttle (see Fig. 53)) to get within
the combustion range required.
Setting LO Fire Offset (while heater is running on
LO Fire):
1. Adjust 0-10 VDC signal to 1 VDC.
2. Wait until Blower RPM reaches 1300 RPM.
3. Using an Allen wrench turn the Offset slightly
clockwise to increase CO
2
values (see Fig. 53).
4. Adjust 0-10 VDC signal back to 10 VDC.
5. Verify combustion is still within range given in
Table U. Adjust if necessary.
Fig. 52: Propane Venturi
BLOWER B BLO BLOW BLOWE BLOWER
SCREW
BLOWER
SCREW
SCREW
BLOWER
SCREW
SCREW
VENTURI VENTURI
Fig. 53: Setting Hi Fire Throttle / LO Fire Offset
HI FIRE THROTTLE HI FIRE TH HI FIRE THRO HI FIRE THROT HI FIRE THROTT HI FIRE THROTTL HI FIRE THROTTLE
(FLAT SCREWDRIVER) HI FIRE THROTTLE
(FL HI FIRE THROTTLE
(FLA HI FIRE THROTTLE
(FLAT SCREWDRIVER)
LO FIRE OFFSET
HI FIRE THROTTLE
(FLAT SCREWDRIVER)
L
HI FIRE THROTTLE
(FLAT SCREWDRIVER)
LO FIRE OFFSET
(ALLEN WRENCH)
HI FIRE THROTTLE
(FLAT SCREWDRIVER)
LO FIRE OFFSET
(ALLEN WRENCH)
GAS VALVE GAS GAS VA GAS VALV GAS VALVE
CAUTION: Adjust the proper throttle on Hi Fire
and/or Offset on LO Fire. Adjustment of the LO fire
offset while the heater is running on Hi Fire may
cause the valve to work improperly and vice versa.
Table U: Gas Valve Settings
GAS VALVE & COMBUSTION SETTINGS - NATURAL GAS
Model
HI Fire LO Fire
Turns Manifold
CO
2
(%) CO (ppm) CO
2
(%)
CO (ppm)
MIN NOMINAL MAX MAX MIN NOMINAL MAX
88AR 3-1/2
-0.1 ±0.05"WC
8.8 9.4 10.5 200 8.5 9.1 10.8 Less than
100
108AR 3-1/2
198AR 4-1/2 -2.0 ± 0.1"WC
278AR 5-3/4 -2.1 ± 0.1"WC
398A 5 -3.4 ± 0.2"WC
GAS VALVE & COMBUSTION SETTINGS - PROPANE GAS
Model
HI Fire LO Fire
Turns Manifold
CO
2
(%)
CO (ppm)
CO
2
(%)
CO (ppm)
MIN NOMINAL MAX
MAX
MIN NOMINAL MAX
88AR 3-1/2
-0.1 ±0.05"WC
10.2 10.5 10.8 200 9.9 10.2 10.5 Less than
100
108AR 3-1/2
198AR 4 -1.4 ± 0.1"WC
278AR 4-1/4 -2.0 ± 0.1"WC
398A 4 -3.0 ± 0.2"WC