• A fireman’s switch is a device installed in a time clock. It turned the heater on 30 minutes after the circulation pump went on and turned the heater off 30 minutes before the circulation pump went off. This was to allow the water to cool down and not damage the plumbing lines. ALL Hayward heaters have Fire Tile, which dissipates the heat immediately, so a fireman’s switch is not required.
• NOTE: Gas fired heaters should be diagnosed and repaired by trained personnel.
  

• Current year model electronic heaters are dual voltage and can operate on 120VAC OR 240VAC. Millivolt heaters do not require an external power supply. ABG heaters require 120V ONLY.
• NOTE: Gas fired heaters should be diagnosed and repaired by trained personnel.
  

Recommended H-Series Heaters for Swimming Pools.

Determine the pool surface area by multiplying the length of the pool in feet by the width. Use the chart above to determine the heater size for your pool.

A note about heater size: A pool heater should heat the pool, on average, one degree an hour. Once the heater is sized to the pool, stepping up one or two sizes will decrease the time to heat.

CAUTION: If you are replacing an existing heater, the new heater size is limited by the diameter of the existing gas supply pipe. Gas pipe is sized according to BTU’s required. Installing a larger heater than the existing pipe can supply will result in a sporadic or non-operating heater.

• Hayward heaters can be converted to use NG or LP. The heater may require a new gas valve, burner orifices and/or air restrictor plate upon conversion. Hayward offers conversion kits through your local Hayward dealer. A licensed or certified gas professional will need to perform the conversion.
• NOTE: Gas fired heaters should be diagnosed and repaired by trained personnel.
  

• The best way to drain the H100ID1 above ground pool heater is to disconnect the gas and plumbing lines and tilt the heater so all the water is removed. Please make sure to close off the water supply and turn the gas supply off prior to disconnecting the plumbing. You can also use an air compressor or shop vac to blow the water out of the plumbing lines

• The best way to save on pool heating costs is to obtain a thermal barrier. Most of a pool’s heat is lost during the evening, through evaporation. By using a solar cover or other thermal barrier, less heat is lost and less gas is needed to bring the pool back to desired temperature.
• NOTE: Gas fired heaters should be diagnosed and repaired by trained personnel.
  
  

• There are specific venting requirements and clearance distances that must be met to ensure proper operation. Consult the owner’s manual for exact specifications for your model of heater.
• NOTE: Gas fired heaters should be diagnosed and repaired by trained personnel.
  
  

• Inadequate water flow caused by a dirty filter or closed valves.
• External bypass needs adjusting.
• Reversed water connections.
• Water pressure switch is out of adjustment.
• It is also possible that the thermostat is out of calibration.
  

• The thermostat may be set too low.
• Inadequate gas supply.
• Malfunctioning thermostat.
• You are losing heat faster then you are adding it. (If the heat loss in the pool is greater than the heat input, the heater might be too small or you may need a thermal barrier). Use a thermal barrier to help prevent heat loss
  

• The heat exchanger may be leaking because,
    (1) Chemical imbalance.
    (2) Sanitizer damage.
    (3) Winter freeze damage.
    (4) Failed joints.
• Regardless of the reason, a Hayward service company must be contacted to inspect the failed exchanger. Contact an Authorized Hayward Dealer/technician for examination.