Installation manual
5
ENVISION POOL HEATER INSTALLATION MANUAL
Water Flow and Connections
Water connections are made at the rear of the heater. 
Both water in and out are labeled just above the water 
connections. LEFT REAR = WATER OUT and RIGHT REAR 
= WATER IN. Two in. unions are supplied and are made to 
accept 2 in. rigid PVC pipe. NOTE: Unions can be used for 
quick drainage of your heater and winterizing.
Heater must be piped downstream from filter in the pool • 
return line.
In-line chlorinators must be piped downstream from • 
heater. A check valve must be installed between the 
heater and chlorinator to prevent drain back of the 
chlorine when the pump is off. A chemical trap may 
also be piped at least 6 in. above the height of the 
chlorinator.
When all the plumbing connections are complete, and • 
ample drying time is allowed, run the filter pump and 
check the entire system for water leaks.
Make sure filter is clean and there are no obstructions in • 
the filtering system.
Proper water flow is essential to the performance of your • 
heater. The minimum flow rate is 20 gpm.
Pool
Spa
Auto-
Chlor
Pump
3-Way
Valve
External
Pressure Switch
Filter
Gas
Trap
3-Way
Valve
Heat Pump
Pool Heater
Return
Automatic
Chlorinator
From Main Drain/Skimmer
Check Valve
Chlorine
Gas Trap
Ball Valves
Filter
Pump
In Out
Heat Pump
Pool Heater
Heat Pump
Pool Heater
In Out
Pump
Filter
From Main Drain/Skimmer
Return
Ball Valve - For Flow Rates
Greater than 70 gpm or
Pumps Larger than 1.5 H.P.
Typical Installation
Installation with In-line Chlorinator
Installation with Pool and Spa
Chemical Use
Water quality must be checked regularly and maintained 
within recommended limits at all times. Failure to maintain 
the proper water quality will greatly reduce the life of your 
heater.
Never add chemicals directly into skimmer.• 
Automatic chlorinators must be piped downstream from • 
the heater. A check valve must be installed between 
the chlorinator and heater to prevent raw chlorine from 
draining back into the heater. A chemical trap may be 
piped at least 6 in. above the chlorinator. See Installation 
with In-line Chlorinator diagram above.
The heat exchanger in your heat pump contains a titanium 
inner tube with a PVC outer shell that will withstand almost 
any water chemistry. While the heat exchanger provides 
superior protection against poor water chemistry, it is 
important to maintain adequate water quality to help 
preserve other components in the system such as pumps 
and filters. The following water quality guidelines are listed 
below.
pH Level 7.4 – 7.8• 
Chlorine Concentration 1 – 5 ppm• 
Total Alkalinity 100 – 200 ppm• 
Calcium Hardness 100 – 300 ppm• 










