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BI301D
GENERAL
As stated, this product series applies to underfloor hydronics heating. The basic
components
for an electric energy
heating system typically includes:
1.
Electric Mini-Boiler itself – covered by this manual
2.
Thermostat control – covered by this manual
3.
Plumbing kit or piping material at the boiler itself - Can be ordered as a kit, reference catalog number
EMB-BK.
•
These items are shown on plumbing installation drawing BX301.
4.
Circulating pump - Typically sized for head pressure and system flow requirement, typical catalog number
EMB-P2.
5.
The underfloor circulating tubes and manifolds - Provided and manufactured by others, not covered in
this manual.
APPROVED TUBING/PIPING
When plumbing this boiler and its peripheral parts to the loop system, all plumbing parts and/or tubing must be
sealed to prevent entrance of oxygen.
Use only tubing or polyethylene tubing with oxygen Diffusion Barrier (ie. Heating PEX).
SYSTEM OR WATER FLOW
In order to prevent hi-limiting and assure full 20 year parts life, the piping system/basic plumbing/circulator pump
must be arranged to provide flow greater than minimum GPM (L/min) shown on the cover sheet.
If this is a zoned system, this applies when the smallest zone is operating. If the zoned system is under 600 feet
(183 m) consider WarmFlo model (EMB-W-9).
ROOM THERMOSTAT PLACEMENT
Comfort and proper space heating response is a direct relationship to the room thermostat type and the placement of
the thermostat sensing bulb. Typically an under floor heating system can be broken down into two categories.
•
Energy storage, water tubing is under the concrete or within the sand base
- The controlling
thermostat must have a remote bulb, and this remote bulb must sense the concrete slab temperature (slab
stat). Coordinated with the concrete pour, install a ¾” (19 mm) PVC, minimum bend radius of 7” (178
mm), and locate at approximately center (vertical) of the concrete slab. The thermostat sensing bulb can
later be pushed down this PVC conduit. If the slab is already poured without conduit for slab stat, use
electronic remote sensing thermostat such as Electro Industries’ ES-24-SRO. This type of device only
requires a ¼” (7 mm) hole drilled in the concrete at some center wall location.
•
Quick response, hydronic tubing just under the concrete surface, no flooring material over the
concrete
- In this case, heated water can directly radiate into the room, a standard wall mount room
thermostat is adequate. Mount room thermostat on an inside wall similar to most heating systems.
•
Radiant heat control systems, wall stat or slab stat, with added in-line aquastat
- These systems are
typically made up by the tube/pipe manufacturer/representative and include system controlling features.
The system controlling device is connected to "R" and "W" terminals and must be the main boiler
control. If there is a mixture of zones, an optional aquastat can be used in case flow does not adequately
maintain the loop temperature below approximate 100
°
. Also the thermostat terminals control the pump.
The best connection for the optional aquastat is controlling the electric boiler element 2. Locate the
white/blue jumper on the inside circuit board, cut and install the aquastat switch. Procedure BD002
provides additional information for strap-on aquastats.
ZONE CONTROLLER
If automatic zones and zoning thermostats are part of this system, suggest adding a zone controller which has the
ability to shed stages when the system is operating with smaller zones. If not using a stage shedding zone
controller, a strap-on aquastat may be required to keep the boiler at a reasonable upper temperature, see next
section.
If you only have 2 to 3 zones, the original multi-zone interlock, EB-5415A is still available. This was recently
updated to include 40VA transformer and additional wiring space. In a simple 2-zone arrangement, this controller
will shed stage 2 if only 1 zone is calling (drawing BH013).
