lp-672 Rev. 000 Rel. 002 Date 10.3.18
21
AIR HANDLER
COLD WATER INLET
HOT WATER OUTLET
RECIRCULATION
COLD WATER INLET
HOT WATER OUTLET
Figure 15 - Water Heater with Air Handler without Internal or External Recirculation - NOTE: There is a Built-In Flow Check in the Internal Pump Loop
NOTE:
If Preheat, Internal, or External Recirculation is active when using Air Handler, a solenoid valve must be used to isolate air handler loop when central
heating is not needed.
NOTES:
1. Minimum pipe size should match connection size. Upsize pipe accordingly if greater flow is required.
2. A thermal expansion tank suitable for potable water must be sized and installed within this piping system between the backflow preventer and the cold
water inlet.
3. All circulators should have an integral flow check.
4. Drains and check valve between unit and storage tank will assist in purging air from system.
5. These drawings are meant to demonstrate system piping only. The installer is responsible for all equipment and detailing required by local codes. In
Massachusetts, you must install a vacuum relief valve per 248 CMR.
6. Mixing valve application is optional, but recommended to help prevent scalding.
7. Always shut off power to the water heater or isolate the heater from the system if ANY plumbing work is to be done. Running the water heater without water
will result in dry-firing.
NOTES FOR AIR HANDLER APPLICATION:
1. WHEN USING AN AIR HANDLER, IT IS REQUIRED TO SET THE WATER HEATER INSTALLER PARAMETER 19:SU to AH – AIR HANDLER MODE. THE RECIRCULATION
PUMP WILL RUN ONCE EVERY 6 HOURS FOR 60 SECONDS TO SANITIZE WATER IN THE AIR HANDLER LOOP.
2. MASSACHUSETTS STATE PLUMBING CODE REQUIRES A DISTANCE NO GREATER THAN 50 FEET FROM THE WATER HEATER TO THE FAN COIL IN THE AIR HANDLER.
3. MASSACHUSETTS STATE PLUMBING CODE REQUIRES AN ELECTRONICALLY TIMED CIRCULATOR PUMP TO ACTIVATE
EVERY SIX HOURS FOR 60 SECONDS. THIS CIRCULATOR IS REQUIRED TO BE BRONZE OR STAINLESS.
4. ALL WATER PIPING MUST BE INSULATED.
5. YOU MUST INSTALL A VACUUM RELIEF VALVE PER 248 CMR.
NOTE: THIS DRAWING IS MEANT TO DEMONSTRATE SYSTEM PIPING ONLY. THE INSTALLER IS RESPONSIBLE FOR ALL EQUIPMENT AND DETAILING REQUIRED BY
LOCAL CODES.
NOTE:
These drawings are meant to show system piping concept only. Installer is responsible for all equipment and detailing required by local codes.
NOTE:
Pumps must either be installed indoors or be rated for outdoor installations. This statement does not apply to the built-in pump.
AIR HANDLER
COLD WATE INLET
SOLENOID
HOT WATER OUTLET
RECIRCULATION
COLD WATER INLET
HOT WATER OUTLET
Figure 16 - Water Heater with Air Handler and Recirculation - NOTE: There is a Built-In Flow Check in the Internal Recirculation Pump Loop
