All installations and services must be performed by qualified service personnel.
Yes
No
After gas valve opens, do the burners ignite?
Measure gas supply pressure | No |
at inlet to gas valve. Is it at | |
least 4.5" W.G. for natural gas |
|
or 11" W.G. for L.P. gases? |
|
Yes |
Check ignitor voltage. | No |
during 20 second | |
it should be at least 105 |
|
VAC. |
|
Check gas supply. Open all manual gas control valves serving the unit.
Correct low line voltage
problem or replace ignition
control module.
Yes
Is ignitor positioned
correctly?
Yes
No
Reposition to correct location.
Do burners stay lit | No |
past proof of flame |
|
check? |
|
|
|
Yes
Does the ignition control
module energize the circulating air blower after the 45 second time delay?
Check for blocked or severely
corroded burners or burner orifices.
Clean or replace as required.
Yes
|
|
|
| Measure supply & manifold | No | |||||
|
|
|
| pressures. Are they constant | ||||||
|
| over time and within the allowable |
|
|
| |||||
|
|
|
| ranges? |
|
|
| |||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| ||
|
|
|
| Check DIP switch settings on |
|
|
|
| ||
|
|
|
| ignition control module against |
|
|
|
| ||
No |
|
| those on connection diagram. |
|
|
|
| |||
|
| Is blower still inoperable after |
|
|
|
| ||||
|
|
|
| time delay with DIP switches |
|
|
|
| ||
|
|
|
| set correctly? |
|
|
|
| ||
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
| Yes |
|
|
| ||
|
|
|
|
|
|
|
|
|
| |
|
|
|
| Measure voltage on the |
|
| No |
| ||
|
|
|
|
|
|
| ||||
|
|
|
| circulating air blower |
|
|
| |||
|
|
|
| terminals "CIR N " & |
|
|
|
|
| |
|
|
|
| "HEAT". Is it 120 VAC? |
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Adjust supply pressure to 4.5" W.G. for natural & 11" W.G. for LP gases. Adjust manifold pressure to 3.5" W.G. for natural gas or 10" W.G. for LP gases. If gas pressure fluctuates, a pressure regulator may be required or gas piping
may be too small for flow.
Check wiring to blower. If okay,
replace the ignition control
module.
Yes |
| Yes |
Does the circulating | ||
| air fan come on | |
| when energized? | |
Check for blower wheel
No
Does blower wheel
spin freely?
Yes
No
rubbing against housing or motor shaft spinning freely. Adjust or replace as necessary.
Is blower motor capacitor | No |
working properly? |
|
Yes |
Replace Motor
Replace blower motor capacitor
47
