NOTE: If local codes require a vacuum relief valve, acquire one locally and instal l per valve manufacturer’s instructions.
Combined Potable Water and Space Heating
CAUTION: When this heater is used for both potable water and space heating, observe the following to ensure proper operation.
1.All piping materials and components connected to the water heater for the space heating application shall be suitable for use with potable water.
2.Toxic chemicals, such as used for boiler treatment, shall not be introduced into the potable water used for space heating.
3.If the heater will be used to supply potable water, it shall not be connected to any heating system or components previously used with a
4.When the system requires water for space heating at temperatures higher than 140°F (60°C), a means such as a mixing valve shall be installed to temper the water in order to reduce scald hazard potential.
Pool Heating
When a boiler or water heater is used in a pool heat- ing application, ensure that all the following installation requirements are met.
The XTherm must be equipped with a direct coupled Cold Water Run injector pump for pool applications. The integral wet rotor injector pump system supplied with all H and model 1005 WH XTherm heaters must not be used for pool service. The direct coupled Cold Water Run injector pump package is optional on all H and 1005 WH models and standard on 1505 and 2005 WH and all WHP models. The Cold Water Run system must be set to maintain 120°F at the inlet to the pri- mary heat exchanger on all XTherm models.
To complete installation of the heater, the system sen- sor must be installed in the return water line, upstream of the heater. The supplied electronic operating con- trol is configured to operate as the thermostat. A separate auto limit is shipped loose to be installed in the system piping downstream of the heater outlet. See Fig. 17 for the thermostat/sensor location.
17
CAUTION: Power to the heater should be interlocked with the main system pump to make sure the heater does not fire without the main system pump in operation. Improper flow control can damage the heater. Uncontrolled flow (too high) or restricted flow (too low) can seriously damage the heater. Follow these instructions to make sure the heater is properly installed.
AUTO LIMIT 
(SET AT 110ºF)
*Maximum 4 times the pipe diameter or 12”, whichever is less.
Fig. 17: Single Pool Heater Application
Set the control in Mode 2 for all
Automatic Chlorinators and Chemical Feeders
CAUTION: Combustion air must not be contaminated by corrosive chemical fumes which can damage the heater and void the warranty.
All chemicals must be introduced and completely di- luted into the pool or spa water before being circulated through the heater. Do not place chlorine tablets or bromine sticks in the skimmer. High chemical concen- trations will result when the pump is not running (e.g. overnight). Chlorinators must feed downstream of the heater and have an
NOTE: High chemical concentrates from feeders and chlorinators that are out of adjustment will cause very rapid corrosion of the heat exchanger in the heater. Such damage is not covered under the warranty.