Zodiac Legacy LRZ, Installation And Operation Manual

page 14

enGlisH

Legacy™ Model LRZM Pool/Spa Heater   

|

   Installation and Operation Manual

4.2 

Burner pressure

Confirm that gas supply pressure is correct. If 

the gas supply pressure is less than required, check for 

undersized pipe between the meter and the heater, a 

restrictive fitting, or an undersized gas meter. Gas inlet 

pressures to the heater, when it is operating, are listed 

in Table 2.

 Caution

Burner gas pressure for the Legacy Model LRZ 

natural gas heaters should be set to the values 

listed in Table 2.

The burner pressure may be checked by connect-

ing a manometer to the pressure port on the burner. 

Refer to Figure 5. The pressure will be zero when the 

heater is not running. When the heater is operating the 

burner gas pressure should be the values listed in 

Table 2.

If the burner pressure indicated above is not 

correct, check the gas train for possible problems. 

Check the meter, gas line, gas fittings, and gas shut off 

for under sizing. Check the gas valve inlet for excess 

pipe dope, if all is correct, then it may be necessary to 

adjust the gas valve regulator. To adjust the burner gas 

pressure, first remove the slotted cap next to the inlet 

pressure port on the inlet side of the gas valve. Under 

the slotted cap is a slotted plastic screw which increas-

es the burner pressure when turned clockwise and 

decreases the burner pressure when turned counter-

clockwise.  After measurements, and adjustments if 

necessary, have been made, make sure to replace the 

test point plugs on the inlet and burner pressure ports, 

and the cap on the burner pressure adjustment screw.  

It is extremely important to replace these parts before 

leaving the installation.  Failure to do so can result in 

damage to property or injury or death. 

With the heater 

firing

, the pressure must be within the range shown in 

Table 2. Also check the pressure with the heater off.

4.3 

special precautions for lpG

LPG is heavier than air and can therefore more 

readily collect or “pool” in enclosed areas if provision 

for proper ventilation is not made. Installation of pool 

heaters in enclosed areas such as pits is not recom-

mended. 

Consult any local code and fire protection author

-

ities about specific installation restrictions in your area.

section 5.  Water Connections

5.1 

Water piping

Figure 6 illustrates typical piping for pool equip-

ment in pool/spa combination pools. 

For normal installations, do not install a shutoff 

valve or any kind of variable restriction in the water 

piping between the heater outlet and the pool/spa. In 

special installations where a shut-off valve, diverter 

valve or other variable restriction is required in the 

plumbing between the heater outlet and the pool, 

Zodiac recommends the installation of a pressure relief 

valve on the heater (see Section 5.7). 

Arrangement of pool system components other 

than as illustrated in these diagrams can affect the 

operation of the heater’s water pressure switch. 

Location of the heater above or below the pool water 

surface can also affect operation of the switch. In 

general, the pressure switch can be adjusted to accom-

modate this effect if the heater water connections 

are no more than 1.8 m below the pool water surface 

and no more than 4.5 m above it. See instructions for 

pressure switch adjustment (Section 5.7) in the heater 

start-up section of this manual for more information 

about this.

Note that when pool equipment is located below 

the pool surface a leak can result in large scale water 

loss or flooding. Zodiac cannot be responsible for such 

water loss or flooding or the damage caused by either 

occurrence.

For special installations such as water connec-

tions below the water level of the pool, or for other 

questions consult your local Zodiac dealer.

5.2 

Hydraulic Head loss

To verify that the minimum flows required 

for the heater are met, a hydraulic head loss curve 

is shown in Figure 7. This should be checked when 

installing this heater into a new or existing piping 

system. This should also be consulted when installing 

a new pump.

5.3 

Check Valve installation

 WarninG

A check valve can interfere with the proper 

operation of certain Suction Vacuum Release 

System (SVRS) products. To avoid possible en-

trapment hazard, serious injury, or death, make 

sure to review the operation/owners manual of 

your particular SVRS product before installing 

the check valve.

The heater must be protected from back-siphon-

ing of water, which can result in dry starts. If there is 

any chance of back-siphoning, provide a check valve 

between the pool and the filter pump inlet.