P-K SOLIS™
Gas Fired Boiler
Technical Service 1.877.728.5351
Revised: March 15, 2021
Released: March 15, 2021
Patterson-Kelley 2021
All Rights Reserved.
2701000090 P-K SOLIS NURO Installation and
Owners Manual (Rev A).docx
Page 49
Gas Pressure Adjustment
See rating plate for the minimum and maximum gas pressure of the boiler. The supply pressure during
main burner operation must be greater than the
minimum indicated on the rating plate. Nominal gas
supply pressure is 7” W.C. for natural gas. The gas pressure must not exceed 14” W.C. which is the
maximum allowable pressure on the gas train components. Each boiler is furnished with a manual
shut-off valve which has an integrated test port. This port is located on the upstream side of the valve
body for measuring supply pressure.
The air flow is pre-set at the factory prior to shipment. Gas flow is dependent primarily on fan speed
not upstream gas pressure. The automatic gas valve may have to be adjusted to obtain proper
combustion readings for specific local conditions. A combustion analyzer must be used. Combustion
must be set in accordance with Recommended Combustion Settings for P-K SOLIS Boilers Table
below.
Manual Control Mode for High and Low Fire Adjustment
To adjust/tune combustion, use the NURO’s “Manual Control Firing Rate” mode. To access this mode,
touch the “Info” button in the lower left corner of the screen, and then press “Service” in the lower left.
Next, touch “Press to Activate Manual Control” which will open the “Manual Control Firing Rate” mode.
This test mode should be used when adjusting or tuning the gas safety shut off/control valve.
Once in “Manual Control Firing Rate” mode, a heat request is required. Once the appliance cycles on
and is running in “Manual Control Firing Rate”, use the UP and DOWN arrows or the slider to force the
boiler to operate at low fire, high fire, or anywhere in-between. To prevent the appliance from cycling
off prematurely during adjustment, ensure that any load devices (air handlers, control valves, radiators,
air handling units, etc.) are in operation and are able to shed/dump the heat created by the boiler.
Recommended Combustion Settings for P-K SOLIS Boilers
The P-K SOLIS™ boilers are equipped with a combination gas/air control and gas safety shut off
control valve. The “zero governor” gas valve responds to the variable speed combustion blower in
order to supply the correct air/gas ratio for optimum performance and efficiency.
Fuel
Nominal Gas Pressure
High Fire Setting
Low Fire Setting
% O
2
% CO
2
% O
2
% CO
2
Natural Gas
7" W.C.
4.2 – 5.0
9.1 – 9.5
4.2 – 5.0
9.1 – 9.5
NOTE:
Proper water flow should be established before performing any combustion adjustments to
ensure the boiler doesn’t short-cycle or overheat.
NOTICE!
For high altitude adjustments (greater than 2,000 feet above sea level), see
Appendix B
– Boiler Altitude Derate Schedule
at the end of this manual.
