Munchkin Gas-Fired Hot Water Boiler manual Part 5 Boiler Piping

GAS-FIRED BOILER Boiler Manual

PART 5: BOILER PIPING (CONTINUED)

diagrams, the space heating system is isolated from the boiler loop by the primary/secondary connection.

2.Size the piping and components in the space heating system using recognized design methods.

G.HYDRONIC PIPING WITH CIRCULATORS, ZONE VALVES AND MULTIPLE BOILERS

The Munchkin Boiler is designed to function in a closed loop 15 PSI System. A factory installed water pressure switch will ensure that you have adequate pressure in the system. The Munchkin Boiler will not operate without a minimum of 10 PSI water pressure. This assures you that if the system does have leak, the Munchkin Boiler will lock out (PRO on the display) before it damages the Stainless Steel Heat Exchanger. We have also included a Temperature and Pressure gauge which allows the user to monitor the system pressure and outlet temperature from the Munchkin Boiler. It is important to note that the Munchkin Boiler has a minimal amount of pressure drop and must be calculated when sizing the circulators. Each Munchkin Boiler installation must have an Air Elimination device that will remove air from the system. Install the Munchkin Boiler so the gas ignition system components are protected from water (dripping, spraying, etc.) allowing clearance for basic service of circulator replacement, valves and other. Observe minimum 1” clearance around all un-insulated hot water pipes when openings around pipes are not protected by non- combustible materials. On a Munchkin Boiler installed above radiation level, some states and local codes require a low water cut off device at the time of installation (See Part C this section). If the Munchkin Boiler supplies hot water to heating coils in air handler units, flow control valves or other devices must be installed to prevent gravity circulation of heater water in the coils during the cooling cycle. Chilled Water Medium must be piped in parallel with the heater. Freeze Protection for new or existing systems must use glycol that is specifically formulated for this purpose. It will include inhibitors that will prevent the glycol from attacking the metallic system components. Make

certain that the system fluid is checked for the correct glycol concentration and inhibitor level. The system should be tested at least once a year and as recommend by the producer of the glycol solution. Allowance should be made for the expansion of the glycol solution in the system piping. Example 50% by volume solution expands 4.8% in volume for the temperature increase from 32 F to 180 F, while water expands 3% with the same temperature rise.

Basic steps are listed below, with Illustration, which will guide you through the installation of the Munchkin.

CAUTION

The Munchkin Boiler should not be operated as a potable Hot Water Heater. It should not be used as a direct Hot Water Heating Device.

1.Connect the system return marked “Heater In”.

2.Connect the system supply marked “Heater Out”.

3.Install Purge and Balance Valve or shut off valve and drain on system return to purge air out of each zone.

4.Install a Back Flow preventor on the Cold Feed Make-Up Water line.

5.Install a Pressure Reducing Valve on the Cold Feed Make-Up Water line, (15 PSI nominal on the system return). Check Temperature and Pressure Gauge which should read minimum pressure of 12 PSI.

6.Install a circulator as shown in piping details (this section). Make sure the circulator is properly sized for the system and friction loss.

7.Install an Expansion Tank on the system supply. Consult the tank manufacturer’s instruction for specific information relating to expansion tank installation. Size the expansion tank for the required system volume and capacity.

8.Install an Air Elimination Device on the system supply.

9.Install a drain valve at the lowest point of the system. Note: The Munchkin Boiler can not be drained completely of water without purging the unit with an air pressure 15 PSI.

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