14
INSTALLING AND COMMISSIONING HETA
AQUA KIT K 36-20
1. GENERAL
1.1 Scope
These instructions describe the
function, installation, commissioning
and operation of Heta return-flow
temperature controller K36-20. For
other components such as regula-
tors, refer to the relevant manufac-
turer’s documentation.
Sections marked with [Expert] are
intended for use by qualified profes-
sionals.
Please read these instructions
thoroughly before using the loading
valve assembly for the first time and
store them safely for future refe-
rence.
1.2 Product description
Heta return-flow loading valve
assembly K36-20 is a pre-installed fi-
xture that maintains constant return
water temperature in Heta recessed
fireplaces and stoves.
• Ballcocks with integrated thermo-
meter (flow and return)
• Pressure relief valve to prevent
excessive pressure
• Automatic bleed valve to prevent
air/gas bubbles in the heat exchan-
ger
• Submersible thermostat to turn
the pump on and off depending
on temperature
• Thermal control valve with 60°C
opening temperature
Our packaging is made from recycla-
ble materials.
1.3 Functional description
Heta return-flow loading valve as-
sembly K36-20 prevents the boiler
from sooting by raising the return
water temperature with the help of
a thermal valve (through a bypass).
The constant return-flow tempera-
ture ensures even combustion and
optimal energy utilisation.
1. As long as the water temperature
in the boiler circuit remains below
the control valve opening tempe-
rature, the valve will prevent water
flowing into the accumulation tank.
The pump circulates the water in
the boiler circuit via the bypass, and
as there is less water in the boiler
circuit, it heats up more quickly.
tKR > tPR
tKR = tFIX
tKR < tBY
2. When the temperature in the boi-
ler circuit reaches the control valve
opening temperature, it reduces the
bypass volume flow and opens the
accumulation tank circuit. The cold
return water from the accumulation
tank then mixes with the hot water
T
KR
T
BY
T
PR
