10/22/2008
1
BI302B
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-PK.
These items are shown on plumbing installation drawing BX304.
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. PEX).
WARMFLO AQUASTAT
This model is factory equipped with the WarmFlo
®
comfort module setup specifically for boiler water temperatures.
During installation the sensor must be installed within the pipe well (see Mechanical section) and the controller modulates
or regulates the elements to maintain a preset maximum or preset operating temperature. The circuit board has a
screwdriver adjustment (see Operational Tips section) for setting the operating temperature point.
During initial turn on (slab stat call for heat) both elements come on full. When the water temperature reaches the set
point, the first 4.5 kW element begins turning off and on in an attempt to regulate at this specific temperature. Assuming
proper flow, the element power will regulate to maintain this preset temperature. If Stage 1 is totally off and the
temperature overshoots by 5°, Stage 2 element is also turned off.
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 underfloor 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” PVC, minimum bend radius of 7 inches, 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” hole drilled in the
concrete at some center wall location.
Quick response, hydronics 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.
Comment: If the slab was poured without the conduit, Electro Industries can provide a remote sensing
slab stat with a remote sensor requiring only a ¼” hole. If it is at an inside wall, the ¼” hole need only be
1’ or 2” away from the plate. If it is an outside wall you should go in about 24”. Simply insert the sensor
about 2” and fill with basic silicone to keep the sensor protected within the hole.
