Weil-McLain 310, 80 How It Works, THE BOILER, WITH PhD, GAS-FIRED WATER BOILER - Boiler Manual

12. Burner

Made with high-grade stainless steel construction, the burner uses pre-mixed air and gas and provides a wide range of firing rates.

13. Water outlet pipe (system supply)

14. Water return pipe (system return)

15. Gas connection pipe

16. Control Module

The Control Module responds to signals from the room thermostat, supply water sensor, return water sensor, flue gas sensor and (if used): domestic hot water aquastat, outdoor temperature sensor, and summer/winter switch. The control module automatically adjusts blower speed (and gas flow rate) to match boiler output to space heating and/or DHW heating demand. The control module is accessed by removing top front cover (16a).

17. Transformer

The transformer reduces line voltage from 120 vac to 24 vac, providing 24 vac to the control module for the gas valve and blower signal .

18. Air intake adapter

19. Electrical entrance cover plate

Remove the electrical cover plate to access the line voltage terminal strip (19b) and the low voltage terminal strip (19a). Attach line voltage conduits to the three holes at the left of the line voltage terminal strip for power, CH pump and DHW pump. Route low voltage wires through the opening to the right of the low voltage terminal strip.

20. Boiler drain valve

21. Line voltage receptacle

Use this connection to plug in line voltage meters or tools while working on boiler. Do not exceed 10-amp load.

22. P/T gauge temperature sensor well

The remote sensor for the panel-mounted pressure/temperature gauge inserts into the outlet water pipe here.

23. Flue gas condensate drain connection

Connect condensate drain line to ½" PVC tee here. The condensate trap (23a) and PVC fittings are field-installed.

24. Front door

The front door is sealed to the boiler assembly around its entire perimeter. Two knurled-head screws (24a) secure the door in place.

25. Ignition electrode

The burner flame is ignited by applying a high voltage to the ignition electrode. This causes a spark (from electrode to ground).

26. Flame inspection window

The quartz glass window provides a view of the burner surface and flame.

Part number 550-101-233/0903

TECHNOLOGY

GAS-FIRED WATER BOILER — Boiler Manual

THE BOILER, WITH PhD

PhDtechnology

PhD Technology, Precision hydronic Data, is an intelligent system that delivers Precision hydronic heating and hot water needs while maximizing efficiency by measuring the Data parameters of your heating system.

1.Cast aluminum heat exchanger

2.Heat exchanger access cover

3.Blower

The advanced blower design and air inlet silencer (5a) on Ultra boilers result in very quiet operation.

80 & 105 — Air enters the boiler enclosure through the air intake adapter (18), flows through the enclosure, enters the air inlet silencer (5a), then enters the blower. The blower pulls air through the silencer and pushes it into the venturi (5), where it mixes with gas before entering the burner.

155, 230 & 310 — Air enters the boiler enclosure through the air intake adapter (18), flows through the enclosure, enters the air inlet silencer (5a), then enters the venturi (5). The blower pulls air and gas through the venturi and pushes the mixture into the burner.

4.Gas valve

The gas valve senses the vacuum in the venturi caused by flowing air, and allows gas to flow when power is applied. The manual gas valve (4a) allows shutting off the gas supply for servicing or shutdown. Models 80 and 105 use a sensing line (4b) from the gas valve to the blower outlet so the gas valve references the same pressure as the venturi inlet.

5.Venturi

When air flows through the venturi, it creates a vacuum. This vacuum pulls gas from the gas valve. So gas will only flow if air is flowing. On 80 and 105 models, the gas air mixture enters the burner after the venturi. On 155, 230 and 310 models, the gas/air mixture enters the blower before passing on to the burner.

6.Flue gas sensor

This sensor monitors the flue gas exit temperature. The control module will shut down the boiler if flue gas temperature gets too hot. This protects the flue pipe and the heat exchanger from overheating.

7.Outlet water temperature sensor

This sensor monitors boiler outlet water temperature (system supply). The control module adjusts boiler firing rate so the outlet temperature is correct.

8.Return water temperature sensor

This sensor monitors return water temperature (system return). The control module reduces or increases boiler input, depending on how close the return water temperature is to the outlet water temperature.

9.Temperature and pressure gauge

10.Electronic display & buttons

The 4-digit electronic display is used to:

•Set space heating temperature.

•Show outlet water temperature (normal) or other operating conditions (in Information mode).

•Show boiler status and shutdown or lockout codes for easy troubleshooting.

The buttons allow changing display mode and reset after lockout. The on/off Power switch (10a) turns power to the boiler controls on or off.

11. Flue pipe adapter

–HOW IT WORKS . . .

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