636484
36
Zoom out
Zoom in
Previous page
1/116
Next page
Engineering information and sizing the heat source
6 720 645 817 (2010/09)
36
5 Engineering information and sizing the heat source
5.1 Operating conditions
Tab. 18 provides an overview of the conditions that must be observed, subject to the application and the local
system-specific circumstances.
5.2 Water quality
As there is no pure water for the heat transfer, observe
the water quality. Unsuitable water quality can damage
heating systems due to scaling and corrosion.
Fill the system with clean mains water only that meets
the requirements below.
To protect the appliance from scale damage throughout
its service life and ensure trouble-free, economical
operation, the overall quantity of hardness constituents
in the fill and top-up water of the heating circuit must be
limited.
To check the permitted amounts of water subject to the
fill water quality, either perform the following
calculations or consult the graphs.
Checking the maximum amounts of fill water subject to
water quality
The fill and top-up water has to meet certain
requirements depending on the total boiler output and
the resulting water volume of a heating system.
Use the following formula to calculate the maximum
amount of water that may be introduced without
treatment:
Form. 1 Calculation of the maximum amount of water that
may be introduced without treatment
Ca(HCO
3
)
2
Concentration calcium hydrogen carbonatein mol/m
3
Q Boiler output in kW
V
max
Maximum fill and top-up water over the entire service
life of the boiler in m
3
Information about the calcium hydrogen carbonate
(Ca(HCO
3
)
2
) concentration of the mains water can be
obtained from your water supply utility. If these details
are not included in the water analysis, the concentration
of calcium hydrogen carbonate can be calculated as
follows from carbonate hardness and calcium hardness.
Example
Calculation of the maximum permissible amount of fill
and top-up water V
max
for a heating system with a total
boiler output of 560 kW. The analysis values for
carbonate hardness and calcium hardness are quoted in
the older unit °dH.
Carbonate hardness: 15.7 °dH
Calcium hardness: 11.9 °dH
The following results from the carbonate hardness:
Ca(HCO
3
)
2
=15.dH×0.179 = 2.8mol/m
3
The following results from the calcium hardness:
Ca(HCO
3
)
2
=11.dH×0.179 = 2.13mol/m
3
The lower of the two values calculated from calcium and
carbonate hardness is decisive for calculating the
maximum permissible water volume V
max
.
Form. 2
Δϑ
max
Minimum
boiler water
flow rate
Max. water
flow rate
Minimum
boiler water
temperature
Operating
interruption
Heating circuit
control unit with
heating mixer
Minimum return
temperature
Full load = 30 K
Partial load = 40 K
No requirements
Results from
ΔT=8K
No requirements
To transfer the
max. output
ΔT must be < 30 K
Tab. 18 Suprapur operating conditions
V
max
0.0235
Q
Ca HCO
3
()
2
--------------------------------
×=
.
V
max
0.0235
560 kW
2.13 mol/m
3
------------------------------- -
× 6.2 m
3
==
36


Need help? Post your question in this forum.

Forumrules


Report abuse

Libble takes abuse of its services very seriously. We're committed to dealing with such abuse according to the laws in your country of residence. When you submit a report, we'll investigate it and take the appropriate action. We'll get back to you only if we require additional details or have more information to share.

Product:

For example, Anti-Semitic content, racist content, or material that could result in a violent physical act.

For example, a credit card number, a personal identification number, or an unlisted home address. Note that email addresses and full names are not considered private information.

Forumrules

To achieve meaningful questions, we apply the following rules:

Register

Register getting emails for Junkers MKB 320-3 A at:


You will receive an email to register for one or both of the options.


Get your user manual by e-mail

Enter your email address to receive the manual of Junkers MKB 320-3 A in the language / languages: English as an attachment in your email.

The manual is 15,83 mb in size.

 

You will receive the manual in your email within minutes. If you have not received an email, then probably have entered the wrong email address or your mailbox is too full. In addition, it may be that your ISP may have a maximum size for emails to receive.

The manual is sent by email. Check your email

If you have not received an email with the manual within fifteen minutes, it may be that you have a entered a wrong email address or that your ISP has set a maximum size to receive email that is smaller than the size of the manual.

The email address you have provided is not correct.

Please check the email address and correct it.

Your question is posted on this page

Would you like to receive an email when new answers and questions are posted? Please enter your email address.



Info