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KORAFLEX Optimal FKO

KORAFLEX Optimal FKO represents the widest range of trench heater models. The black lacquered galvanized steel casing comes with optional decorative U-, F- or Cross frames, and a wide choice of grilles.

ECONOMIC version – basic version, black lacquered galvanized steel casing, non-lacquered heat exchanger
EXCLUSIVE version – black lacquered galvanized steel casing, RAL 9005 black lacquered heat exchanger

FKO ikony

ECONOMIC version basic version, black lacquered galvanized steel casing, non-lacquered heat exchanger
EXCLUSIVE version black lacquered galvanized steel casing, RAL 9005 black lacquered heat exchanger
Depth [mm] 70,  90, 110, 130, 150, 190, 300, 450 mm
Width [mm] 140, 200, 260, 320, 400 mm
Length [mm] 800 to 3 000 mm (by 100mm)
Heat output [W] from 41 to 3 480 W
Max. operating pressure [MPa] 1.2 MPa
Max. operating temperature [°C] 90 °C
Connecting thread inner G ½"
Cover grilles Optimal PM
picto info

Where a left-hand connection to the heating system is required, rotate the heat exchanger in the trench heater by 180°.

Cross grille – design solutions – the casing must undergo alternation.


Cross grilles must be ordered together with trench heaters. These trench heaters will be fitted with Cross frame suitable for Cross grille.

Heat output [W] where t1/t2/ti / EN 16430. Measurements shown in mm including U-frame.

ΔT = 50 °C Length [mm] Temperature exponent
Height
[mm]
Width
[mm]
800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 2400 2500 2600 2700 2800 2900 3000
70 140 42 51 61 71 81 91 101 111 121 130 140 150 160 170 180 190 200 210 219 229 239 249 259 1,4629
70 200 76 90 105 120 135 150 165 179 194 209 224 239 254 268 283 298 313 328 342 357 372 387 402 1,4587
70 260 90 108 126 143 161 179 196 214 232 250 267 285 303 320 338 356 373 391 409 426 444 462 480 1,6148
70 320 102 124 146 168 189 211 233 255 276 298 320 342 364 385 407 429 451 472 494 516 538 559 581 1,5550
70 400 131 157 183 208 234 260 286 311 337 363 389 414 440 466 492 517 543 569 595 620 646 672 698 1,5235
90 140 50 62 74 86 98 110 122 134 146 158 170 182 194 206 218 230 242 254 266 278 290 302 314 1,5247
90 200 120 143 167 191 214 238 261 285 308 332 355 379 402 426 449 473 496 520 543 567 590 614 637 1,5373
90 260 153 183 213 243 273 303 333 363 393 423 453 483 513 543 573 603 633 663 693 723 753 783 813 1,5643
90 320 195 236 278 319 361 402 444 485 526 568 609 651 692 733 775 816 858 899 940 982 1023 1065 1106 1,4599
90 400 275 329 383 437 490 544 598 652 706 760 814 868 922 976 1029 1083 1137 1191 1245 1299 1353 1407 1461 1,4607
110 140 55 69 82 95 108 122 135 148 161 174 188 201 214 227 240 254 267 280 293 307 320 333 346 1,4888
110 200 142 170 198 226 254 282 309 337 365 393 421 449 477 505 532 560 588 616 644 672 700 728 755 1,4739
110 260 184 220 257 293 329 365 401 437 473 510 546 582 618 654 690 726 763 799 835 871 907 943 979 1,4385
110 320 237 287 338 388 438 489 539 589 640 690 740 791 841 891 942 992 1042 1093 1143 1193 1244 1294 1344 1,4622
110 400 327 391 455 520 584 648 712 776 840 905 969 1033 1097 1161 1225 1289 1354 1418 1482 1546 1610 1674 1739 1,4569
130 140 79 95 110 126 141 157 172 188 203 219 234 250 265 281 296 312 327 343 358 374 389 405 420 1,5855
130 200 144 172 200 228 256 284 313 341 369 397 425 453 481 510 538 566 594 622 650 679 707 735 763 1,5143
130 260 203 243 283 323 363 403 443 482 522 562 602 642 682 722 761 801 841 881 921 961 1001 1041 1080 1,6077
130 320 284 340 395 451 506 562 618 673 729 785 840 896 952 1007 1063 1119 1174 1230 1286 1341 1397 1453 1508 1,5011
130 400 364 435 506 578 649 720 791 863 934 1005 1077 1148 1219 1291 1362 1433 1505 1576 1647 1718 1790 1861 1932 1,5119
150 140 92 109 127 145 163 181 199 217 235 253 271 289 307 325 343 361 379 397 414 432 450 468 486 1,5470
150 200 154 185 215 245 276 306 336 366 397 427 457 488 518 548 578 609 639 669 700 730 760 790 821 1,5528
150 260 238 284 331 378 424 471 517 564 611 657 704 751 797 844 890 937 984 1030 1077 1124 1170 1217 1263 1,5240
150 320 314 376 438 499 561 623 684 746 808 869 931 992 1054 1116 1177 1239 1301 1362 1424 1486 1547 1609 1671 1,5165
150 400 389 465 541 617 693 770 846 922 998 1074 1151 1227 1303 1379 1455 1531 1608 1684 1760 1836 1912 1989 2065 1,5296
190 200 172 205 239 273 306 340 374 407 441 475 508 542 576 610 643 677 711 744 778 812 845 879 913 1,5264
190 260 260 311 362 413 464 515 566 617 668 719 770 821 872 923 974 1025 1076 1127 1178 1229 1280 1331 1382 1,4983
190 320 384 459 534 609 685 760 835 910 986 1061 1136 1211 1287 1362 1437 1512 1588 1663 1738 1813 1888 1964 2039 1,5283
190 400 526 629 732 835 938 1041 1144 1248 1351 1454 1557 1660 1763 1866 1969 2072 2175 2278 2382 2485 2588 2691 2794 1,5329
300 260 308 368 428 489 549 610 670 730 791 851 911 972 1032 1092 1153 1213 1273 1334 1394 1454 1515 1575 1635 1,4820
300 320 457 546 636 725 815 904 994 1083 1173 1262 1352 1441 1531 1620 1710 1799 1889 1978 2068 2157 2247 2336 2426 1,4769
300 400 559 669 778 888 998 1107 1217 1327 1436 1546 1656 1765 1875 1985 2094 2204 2313 2423 2533 2642 2752 2862 2971 1,4734
450 260 426 510 593 677 761 844 928 1011 1095 1178 1262 1346 1429 1513 1596 1680 1764 1847 1931 2014 2098 2181 2265 1,4575
450 320 506 605 704 803 902 1001 1100 1200 1299 1398 1497 1596 1695 1794 1893 1993 2092 2191 2290 2389 2488 2587 2687 1,4849
450 400 655 783 912 1040 1168 1297 1425 1554 1682 1810 1939 2067 2196 2324 2452 2581 2709 2837 2966 3094 3223 3351 3479 1,4713

Standard contents

  • RAL 9005 black laquered galvanized steel casing
  • Economic – non-lacquered Al/Cu heat exchanger with bleed valve
  • Exclusive – RAL 9005 black lacquered Al/Cu heat exchanger with bleed valve

  • aluminium U-frame silver elox
  • metal cover plate
  • levelling set screws and 4 anchors
  • spacers for correct installation and concreting
  • hardboard cover to protect trench heater from contamination
  • durable packaging, installation instructions


 

Optional accessories

  • choice of grilles
  • Cross grille – design solutions – necessary to order together with trench heater
  • light/dark bronze and black elox or RAL colour chart laquered aluminium U-frame
  • silver, light/dark bronze and black elox or RAL colour chart lacquered aluminium F-frame
  • thermostatic head with incorporated control and immersion remote sensor
  • 24V DC power supply
  • 24V DC or 230V AC room thermostat for regulation
  • 24V DC or 230V AC thermoelectric actuator, 2.5m or 5m cable length
  • raised floor structural supports
  • lockshield, thermostatic valve
  • ½" × ½" 90° brass elbow for connection facilitation
  • 10, 12 or 30cm flexible stainless steel hose
  • strengthened OSB cover for installation purposes

TRENCH HEATER COMPONENTS

                                    

Složení konvektoru FK_1 

1black laquered galvanized steel casing

2choice of grille (please order separately)

3choice of aluminium frame

4Al/Cu heat exchanger

54 anchors

6levelling set screws

7metal cover plate

8brackets

9spacers for correct installation and concreting

Frames

Standard U-frame                        Optional F-frame                         Optional Cross grille frame (on request)

Optimal - rámečky

Suitable grilles

Roll-up aluminium silver

fk_mrizka_AL_stribrna

Linear aluminium silver fk_mrizka_AL_stříbrná_podélná
Roll-up aluminium dark bronze

fk_mrizka_AL_tmavý bronz

Linear aluminium dark bronze

fk_mrizka_AL_tmavý bronz_podélná

Roll-up aluminium light bronze

fk_mrizka_AL_světlý bronz

Linear aluminium light bronze

fk_mrizka_AL_světlý_bronz_podélná

Roll-up aluminium black elox - NEWS
Koraflex-PM-pricna-matny-cerny-elox
Linear aluminium black elox - NEWS
Koraflex-PM-podelna-matny-cerny-elox
Roll-up steel

fk_mrizka_podelna_ocel

Linear steel

PM_mrizka_podélná_ocel_1

Roll-up stainless steel

fk_mrizka_podelna_nerez_ral (2)

Linear stainless steel

PM_mrizka_podélná_nerez_1

Roll-up natural / lacquer beech 

fk_mrizka_drevo_buk

Roll-up natural / lacquer oak

fk_mrizka_drevo_dub

Roll-up natural / lacquer mahogany
(upon request)

fk_mrizka_drevo_mahagon

Cross
(upon reques)Cross_2

KORAFLEX OPTIMAL FKO  -  PRODUCT RANGE 

U = U-frame F = F-frame 

KORAFLEX_Optimal_19

Width of trench heaters fitted with a Cross frame are identical to trench heaters fitted with an U-frame. Where the F-frame is fitted, both the length and width increase by 30 mm.

​FK TRENCH HEATER INSTALLATION

Construction recommendations

To ensure correct operation, it is essential that the following principles are respected.

  • Trench heaters must be installed horizontally with the heat exchanger on the window side. For the grille to function correctly, the upper edge of the casing must be straight and level (not buckled or bent).
  • The maximum recommended distance of the trench heater from the wall/window is 100 mm.
  • The size of the trough in the floor for thrench heater installation should be at least 100 mm bigger (both in length and width) than the convector.
  • We recommend connecting the trench heater to the heating system using a lockshield and thermostatic valve. The heat exchanger connection is by an inner G½ thread. Following connection to the heating system, bleed and carry out a pressure test.
  • When concreting, the trench heater must be levelled using the set screws provided and fastened to the floor using the anchors provided. The anchors keep the trench heater in place while pouring concrete.
  • Using anchors will extend the bottom width of the trench heater by 42 mm from each side.
  • While pouring concrete, the trench heater may be weighed down.
  • While pouring concrete it is particularly important to brace the trench heater to prevent longitudinal buckling. Trench heaters are fitted with spacers for this purpose. (Please note: FKP models as standard are, however, not equipped with spacers.) Following concreting, these spacers are easily removed.
  • While pouring concrete or anhydrite it is essential to seal all connection openings to prevent leakage.
  • Where the trench heater is not concreted in, floor supports are recommended to use to incorporate the trench heater into a raised floor. Standard trench heater models are not self-supporting.
  • We recommend insulating the outer side of the trench heater casing along the length of the heat exchanger with polystyrene to prevent heat loss into the floor.
  • To avoid contaminating the trench heater, we recommend maintaining the protective hardboard cover in place during construction work. The board, which is included in the standard contents, is not suitable for walking on and serves solely to protect the trench heater from contamination during installation. Strengthened OSB covers for installation purposes are available as option extras.
  • Trench heaters fitted with stainless steel casings installed in humid environments – marked KORALEX Pool FKP – are equipped as standard with overflow drains. During installation the pipe at the bottom of the trench heater must be connected to piping with sufficient gradient to drain overflow water. We recommend installing a U-bend to prevent odour.

Raised floor installations

  • ​Structural supports for raised floor trench heater installations offer stable and effective solutions. Structural supports are manufactured from non-lacquered steel and are suitable for raised floors of a depth up to 500 mm. Structural supports are suitable for Optimal FKO and Basic FKB models.

Zdvojená podlaha

picto info

Supports must be ordered together with trench heaters due to structural alterations to convector casings! Components of several types of raised floor support are integral parts of the trench heater body.


 

 

 

FK - montaz konvektoru - 1-bez  FK - montaz konvektoru - 2-bez

1 - trench heater with natural convection, 2 - heat exchanger, 3 - grille, 4 - U-frame, 5 - F-frame,
6 - set screws, 7 - anchors, 8 - up to 300mm deep dividing partition, 9 - window,  10 - floor level, 
11 - grout, 12 - expansion joint, 13 - insulation, 14 - concrete filler, 15 - sub-floor

 

Alterations to technical specifications reserved

 

Recommended positioning of heat exchangers in trench heaters

  • Trench heaters should be positioned a maximum of 100 mm from windows. In order to achieve maximum performance, the recommended position for heat exchangers in the trench heater is always on the window side. This results in natural air flow, whereby warm air rises and cool air is drawn into the trench heater. In this way, cool air at the window is screened and the air in the room is heated.

Trench heaters are fitted as standard with right-hand connections to the heating system; a left-hand connection is achieved simply by rotating the heat exchanger 180°.

přirozená konvekce

 

Trench heater multiple installations

Casing types according to water connections and lowered sides for multiple installations

Lowered trench heater casing sides are used where invisible connections are desired between trench heaters (multiple trench heaters around a room, eg. in administrative buildings, restaurants, hotels, etc.). When ordering grilles, care must be taken to include information in the order code that the grilles required are to be used with trench heaters with lowered faces.

připojení FK

ORDER CODE

Example order code: Fko-100/11/26-V1u1p0

KORAFLEX trench heater with natural convection, Optimal model, length 100 cm, depth 11cm, width 26 cm, counter-flow non-lacquered heat exchanger, U-frame silver elox, right-hand connection to heating system, without lowered face.

KORAFLEX Convection Optimal   Length/Depth/Width (cm)   Heat exchanger
type
Heat exchanger
colour
Frame Frame colour Connection
side
Lowered
face
F K O - 100/11/26 - V 1 U 1 P 0

 

 

 

 

 

 

V counter-flow
P* single-stream
0 without heat
exchanger

1 non-lacquered
5 RAL 9005
9 other colour RAL
0 without heat
exchanger

U U-frame
F F-frame
C for Cross grille
0 without frame

1 silver elox
2 dark bronze elox
3 light bronze elox

5 black elox
9 other RAL colour
0 without frame

right

0 without lowered face
1 lower face – input side
2 lower face – opposite input side
3 both sides lower

P* – single-stream heat exchangers are fitted as standard in trench heaters 140 mm wide, depth of 70, 90 and 110 mm only.

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