Munchkin Gas-Fired Hot Water Circulating Heater installation manual Circulator Sizing

GAS-FIRED HEATER Installation Manual

PART 5: MUNCHKIN CONTENDER PIPING (CONTINUED)

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 Contender should not be operated as a potable Hot Water Heater.

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 Contender can not be drained completely of water without purging the unit with an air pressure 15 PSI.

10.The Safety Relief Valve is installed at the factory. Pipe the discharge of the safety relief valve to prevent injury in the event of pressure relief. Pipe the discharge 6” above the drain to a drain. Provide piping that is the same size as the safety relief valve outlet. Never block the outlet of safety relief valve.

H. CIRCULATOR SIZING

The Munchkin Contender Heat Exchanger does have pressure drop which must be considered in your system design. Refer to the graph in Fig. 5-1 below for pressure drop through the Munchkin Contender Heat Exchanger for rec- ommended pump selection at a 20∆t design.

Figure 5-1

* NOTE: The recommended circulators are based on 1 gpm per 10,000 btu/hr with 20°∆t.

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