Piping Schematic for EMBLEM® Hybrid Boiler System Two Medium Mass Condensing Boilers and Two PRIMERA® Instantaneous Non-Condensing Boilers

Medium Mass

Condensing Boiler 2

Medium Mass

Condensing Boiler 1

PRIMERA Boiler 1

PRIMERA Boiler 2

34 –851 8.10 RIVERSIDE HYDRONICS, LLC · FORT WORTH, TEXAS · (800) 990-5918 Copyright © Riverside Hydronics

See note 1 for pipe sizing

Primary-Secondary Common Pipe Interface

Maximum 4 pipe diameters from point A to B (see note 6)

A B

Circulator

Thermostatic Mixing Valve

Swing Check Valve

Motorized Shutoff Valve

Full Port Isolation Ball Valve

Flow Control Valve

Union

See note 3 for motorized shutoff valves

Notes: 1. Piping shared by multiple PRIMERA boilers, must be sized for the total anticipated flow at the

proper velocity for the piping material. 2. PRIMERA pump sizing must be confirmed for the required boiler flow rate (gpm) against the

head loss of the boiler and the primary boiler piping system to and from the header. 3. Do not use motorized shutoff valves on the medium mass boilers in a constant flow boiler loop.

They are optional on variable flow loops, but should be controlled by a relay on the boiler and not remotely through the Building Automation System. Precaution must be taken to prevent “dead-heading” the system circulator. Consult Riverside Hydronics for recommendations. Motorized shutoff valves should never be used on PRIMERA instantaneous boilers.

4. Medium-mass condensing boilers should be piped reverse return with direct flow-through from the building loop. PRIMERA boilers must be piped primary-secondary with a dedicated circu-lator installed for each boiler.

5. Depending upon maximum building flow, larger return and supply fittings (factory option) may be a consideration for the medium mass boilers.

6. Whenever PRIMERA boilers are operating, the total building flow must be 125% of the required flow of all PRIMERA boilers operating at that time.

7. Refer to individual boiler installation manuals for more details.

See note 2 for pump sizing

Building Circulator

Normally closed bypass

OnTrac® Loop Sensor

Expansion Tank

Air Separator

Makeup Line

M

M

M

Maintain minimum boiler loop static pressure of 15 psi in the boiler room.