LAARS HP-M2 Series - Installation, Operation and Maintenance Instructions - Manual (Page 19)

H Series Page 19
SECTION 9.
Check, Test and Start Up
9A. Filling System
1. Open all supply and return valves.
2. Fill heating system to minimum operating
pressure of 12 psig.
3. Open bleed pet cock and bleed air from boiler
coil until a good stream of water comes out.
(H(P)-M2 series), Item 8 on page 33.
4. Purge all lines by opening vents, or with flushing
valves.
5. Close gas valve.
6. Turn on 120 volt power, and listen for unit
circulator to start. Unit will cycle off on lockout.
7. Open all vents again to discharge any additional
air and close off after air is eliminated.
8. System is now ready for operation.
9B. Firing Burner
1. Be sure that system has been filled properly (see
above) and is leak tight.
2. Open gas cock (s). Open manual gas shutoff
valve by turning to “on” position.
3. Turn on main switch, and set thermostat to call
for heat. In approximately 2 seconds, blower will
come on.
NOTE: Burner may not ignite on first attempt
because of air in gas lines. In this case, blower will
stop after 5 minutes. Should this happen, turn off main
switch. Wait 5 minutes and turn on main switch again.
4.
If burner fails to ignite after three attempts, refer
to Trouble Shooting Section 2, Service Manual
or call service for troubleshooting.
Caution
Should any pronounced odor of gas be detected, or
if the gas burner does not appear to be functioning
in a normal manner, close main shutoff valve, do
not shut off switch, and contact your heating
contractor, gas company, or factory representative.
5. You MUST check flame monitoring control
(ignition system safety shutoff device).
a.
Close gas cock with burner operating.
b. In 3 seconds, FLAME indicator light will
go out and blower will continue to run on
post purge cycle. Two additional attempts
to light will follow including pre-purge,
igniter on, valve/flame on and post purge.
(Ignition will not occur-gas off.)
c. Open gas cock. Switch unit “OFF” and then
“ON” again. Burner should start after about
45 seconds. It is recommended that the unit
be checked with a standard CO² or O²
tester. Insert tester probe at least 6" into
exhaust pipe through outside vent terminal.
Readings should be:
CO2 - 8% to 8.5% (nat. gas)
CO2 - 9% to 9.8% (LP gas)
O2 - 7% to 4½%
6. Check Burner Input (other equipment off)
a. Measure the time, in seconds, it takes to use
one cubic foot of gas.
b. Divide the number of seconds into 3,600.
c. Multiply the result by the heating value of
the gas to obtain BTU/HR input.
Example: If it takes 36 seconds to use one cubic
foot of gas and the heating value of the gas is
1,000 BTU/CU FT, (approx. natural gas value).
INPUT = 3,600/36 x 1,000 = 100,000 BTU/HR
Input Ranges
H(W)-M2-130 - 127,400 TO 132,600 BTU/HR
H(W)-M2-100 - 98,000 TO 102,000 BTU/HR
H(W)-M2-60 - 58,800 TO 61,200 BTU/HR
Because of the altitude and other minor
variations, it is possible the input will not fall within
this range and the gas orifice must be replaced. See
chart in an orifice kit.
9C. Check Limit Control Operation
9C-1. Operating and Low Limit
Control HW-M2
When water temperature reaches low limit set
point (180°F) with no call for heat, H Series will shut
down.
Turn up the room thermostat. Boiler pump
(inside jacket) will now run.
If water temperature is below operating control
cut out temperature (210°F) burner will fire.
When operating control cut-out temperature is
reached (210°F) burner will go off, blower will post
purge for 30 seconds and the boiler pump and system
circulator will continue to operate until room
thermostat is satisfied.
When water temperature drops below low limit
cut-in temperature (150°F) and there is a continued
call for heat, the system circulator will go off. The
boiler pump will continue to operate and the burner
will remain on. When low limit cut-out temperature is
reached (180°F) the system circulator will come on.
OUT OF
PRODUCTION