Camus Hydronics DRW1000, Инструкция по установке и обслуживанию

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DR 3000 – DR 5000
11.9 DOMESTIC HOT WATER HEATER
Hot water heaters are designed for installation with a storage
tank. The operation of the properly sized circulating pump, the
piping between the tank and heater and the control of water
velocity, as explained below, are important for correct operation
of your hot water heater.
11.10 WATER VELOCITY CONTROL
To ensure proper velocity through the heat exchanger(s), it is
necessary to select the proper pump. Temperature rise at full
fire will be an indication of flow. This must be done on initial
installation and periodically rechecked.
Excessive lime/scale build-up in the heat exchanger tubes is a
result of restricted flow and too little velocity in the tubes. Care
should be taken to maintain required water velocity based on
water condition as follows:
11.11 TEMPERATURE RISE AT FULL FIRING RATE
1 The pump must run continuously when the burner is firing.
2 With the pump running and the burner in the appliance in
the off cycle, the inlet temperature and outlet temperature
readings on the display should read approximately the
same temperatures.
3 Turn the hot water heater on and allow time for the
temperature to stabilize. Check the temperature rise when
the burner is firing at 100% of rated input.
4 Compare the temperature rise on the Dynaforce® display
with the required temperature rise at the required flow rate
based on water condition (Soft, Normal, and Hard). Should
adjustment be needed, proceed as follows:
If the temperature rise is too high, the water velocity is too
low. Adjust as follows:
1 Check for flow restrictions. Check for debris in strainers
2 Check diameter and equivalent length of the piping
between the storage tank and hot water heater.
3 Be sure all valves are open between the hot water heater
and the storage tank. Ensure that all ball valves are fully
ported.
4 Check the pump to be sure it is running properly and that
the pump motor is running in the proper direction.
5 Be sure the pipes between the hot water heater and storage
tank are not more than a total of 80 equivalent feet between
inlet and outlet lines. If maximum equivalent length for the
specified pipe diameter is exceeded, larger diameter pipe
may have to be installed to achieve correct flow and
temperature rise.
6 Common manifold piping for multiple unit installations will
require larger minimum pipe sizes and tank circulating
tapping to ensure proper flow.
If the temperature rise is too low, the water velocity is too
high. Adjust as follows:
1 Temperature rise can be increased by slowly closing the
flow control valve (globe valve or flow setter) in the outlet
piping from the hot water heater to the storage tank to
achieve the proper temperature rise.
2 Sustained high water velocity and low temperature rise may
result in pitting or erosion of the stainless steel tubes in the
heat exchangers. This is a non-warrantable failure.
Temperature rise must be properly adjusted to achieve the
specified flow rate.
The required temperature rise and the recommended pump size
are based on the heating of potable water with normal hardness.
For DHW applications with other than normal hardness, choose
a pump for the local water hardness conditions. Alternatively,
soften the water to normal levels. Damage to the heat exchanger
as a result of scaling or corrosive water conditions in non-
warrantable.
CAUTION
Temperature rise cannot be adjusted when the burner is firing
at less than 100% of input rate.
11.12 WATER HEATERS
The manufacturer recommends the use of a properly sized
thermostatic mixing valve to supply domestic hot water at
temperatures less than 140°F (60°C). Storing the water at a
higher temperature and thermostatically mixing the water will
decrease the size of the storage tank and increase the available
quantity of mixed hot water.
• Piping components connected to the water heater for a
space heating application shall be suitable for use with
potable water.
•
Toxic chemicals, used for boiler treatment, shall not be
introduced into the potable water used for space heating
•
A water heater which will be used to supply potable water
shall not be connected to any heating system or
component(s) previously used with a non-potable water
heating appliance
•
When a system requires water for space heating at
temperatures higher than required for other uses, a means
such as a mixing valve shall be installed to temper the
water for those uses in order to reduce scald hazard
potential.
CAUTION
Adequate care MUST be taken to prevent potential scald
injury when storing water at 140°F (60°C) and hotter.
WARNING
Should overheating occur or the gas supply fail to shut off, do
not turn off or disconnect the electrical supply to the pump,
instead, shut off the gas supply at a location external to the
appliance.