State Water Heaters Utra-Force STC-077, Service Handbook

Page: 32 / 46

S U F S E R V I C E H A N D B O O K
T R O U B L E S H O O T I N G
State Water Heaters Technical Training Department
Ashland City, Tennessee © 2004
31
STC-077
GAS PRESSURE CHECK
STEP 13: CHECK AND ADJUST SUPPLY GAS PRESSURE.
Attach manometer or gas pressure gauge to pressure tap on gas valve or use adapter to check
pressure ahead of valve as near as possible to valve. All appliances being served by this gas sup-
ply line should be operating.
STEP 14: CHECK AND ADJUST MANIFOLD GAS PRESSURE.
STEP 13 SUPPLY GAS PRESSURE TEST
IF... THEN
supply gas pressure is not between 5.0 and 14” W.C.
natural gas or 11.0 and 14” W.C. propane adjust supply gas pressure (Recommended supply
minimum is 7.0” W.C. for natural gas models)
proper supply gas pressure is present continue to Step 14.
STEP 14 MANIFOLD GAS PRESSURE TEST
IF... THEN
manifold gas pressure is not:
natural gas models
3.5” W.C. ± 0.3” – SUF 155 & 199
4.0” W.C. ± 0.3” – SUF 240
propane gas models
10.0” W.C. ± 0.3” – all propane gas models. adjust manifold gas pressure to values given for model
and fuel type (within 0.3” W.C. tolerance)
if manifold gas pressure cannot be adjusted to
maintain values given (within 0.3” W.C. tolerance)
replace gas valve.
manifold gas pressure is within tolerances given above ignition should occur.
SUF 150, 199
Propane
SUF 240 Natural
Gas Valve
SUF 150, 199
Natural
Gas Valve