Munchkin Gas-Fired Hot Water Circulating Heater - Manual (Page 16)

15
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.
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.
CAUTION
The Munchkin Contender should not be
operated as a potable Hot Water Heater.
Figure 5-1
* NOTE: The recommended circulators are based on 1 gpm per 10,000 btu/hr with 20°
∆t.