CBSE Class 12 Air Conditioning and Refrigeration Question Paper 2020

H$moS> Z§. 351
Code No.
amob Z§. narjmWu H$moS >H$mo CÎma-nwpñVH$m Ho$ _wI-n¥ð
Roll No. >na Adí` {bIo§ &
Candidates must write the Code on the
title page of the answer-book.

ZmoQ> NOTE
(I) H¥$n`m Om±M H$a b| {H$ Bg àíZ-nÌ _o§ _w{ÐV (I) Please check that this question
n¥ð> 7 h¢ & paper contains 7 printed pages.

(II) àíZ-nÌ _| Xm{hZo hmW H$s Amoa {XE JE H$moS (II) Code number given on the right
>Zå~a H$mo N>mÌ CÎma-nwpñVH$m Ho$ _wI-n¥ð> na hand side of the question paper
{bI| & should be written on the title page of
the answer-book by the candidate.
(III) H¥$n`m Om±M H$a b| {H$ Bg àíZ-nÌ _| (III) Please check that this question
>42 àíZ h¢ & paper contains 42 questions.
(IV) H¥$n`m àíZ H$m CÎma {bIZm ewê$ H$aZo go (IV) Please write down the Serial
nhbo, CÎma-nwpñVH$m _| àíZ H$m H«$_m§H$ Number of the question in the
Adí` {bI| & answer-book before attempting it.
(V) Bg àíZ-nÌ H$mo n‹T>Zo Ho$ {bE 15 {_ZQ >H$m (V) 15 minute time has been allotted to
g_` {X`m J`m h¡ & àíZ-nÌ H$m {dVaU read this question paper. The
nydm©• _| 10.15 ~Oo {H$`m OmEJm & question paper will be distributed
10.15 ~Oo go 10.30 ~Oo VH$ N>mÌ Ho$db at 10.15 a.m. From 10.15 a.m. to
10.30 a.m., the students will read the
àíZ-nÌ H$mo n‹T>|Jo Am¡a Bg Ad{Y Ho$ Xm¡amZ question paper only and will not
do CÎma-nwpñVH$m na H$moB© CÎma Zht {bI|Jo & write any answer on the
answer-book during this period.

dmVmZwHy$bZ Ed§ àerVZ
AIR-CONDITIONING AND REFRIGERATION

{ZYm©[aV g_` : 3 KÊQ>o A{YH$V_ A§H$ : 60
Time allowed : 3 hours Maximum Marks : 60

.351 1 P.T.O.

gm_mÝ` {ZX}e :
{ZåZ{b{IV {ZX}em| H$mo ~hþV gmdYmZr go n{‹T>E Am¡a CZH$m g™Vr go nmbZ H$s{OE :
(a) Bg àíZ-nÌ _| Xmo IÊS> h¢  IÊS> H$ … amoOJma H$m¡eb Am¡a IÊS> I … {df` H$m¡eb &
(b) IÊS> H$ … amoOJma H$m¡eb (10 A§H$)
(i) {XE JE 6 àíZm| _| go {H$Ýht 4 àíZm| Ho$ CÎma Xr{OE & àË`oH$ àíZ 1 A§H$ H$m h¡ &
(ii) {XE JE 5 àíZm| _| go {H$Ýht 3 àíZm| Ho$ CÎma Xr{OE & àË`oH$ àíZ 2 A§H$ H$m h¡ &
(c) IÊS> I … {df` H$m¡eb (50 A§H$)
(i) {XE JE 12 àíZm| _| go {H$Ýht 10 àíZm| Ho$ CÎma Xr{OE & àË`oH$ àíZ 1 A§H$ H$m h¡ &
(ii) {XE JE 7 àíZm| _| go {H$Ýht 5 àíZm| Ho$ CÎma Xr{OE & àË`oH$ àíZ 2 A§H$ H$m h¡ &
(iii) {XE JE 7 àíZm| _| go {H$Ýht 5 àíZm| Ho$ CÎma Xr{OE & àË`oH$ àíZ 3 A§H$ H$m h¡ &
(iv) {XE JE 5 àíZm| _| go {H$Ýht 3 àíZm| Ho$ CÎma Xr{OE & àË`oH$ àíZ 5 A§H$ H$m h¡ &
(d) Bg àíZ-nÌ _| 42 àíZ em{_b h¢ {OZ_| go 30 àíZm| Ho$ CÎma XoZo h¢ &
(e) g^r àíZm| Ho$ {deof ^mJ /IÊS> H$mo ghr H«$_ _| H$s{OE &
(f) A{YH$V_ g_` 3 K§Q>o h¡ &
IÊS> H$
(amoOJma H$m¡eb) (10 A§H$)
{XE JE 6 àíZm| ‘| go {H$Ýht 4 àíZm| Ho$ CÎma Xr{OE & à˶oH$ àíZ 1 A§H$ H$m h¡ & 14=4
1. g§Mma H$m¡eb Š`m h¢ ? 1
2. ñbmBS> go AmnH$m Š`m VmËn`© h¡ ? 1
3. ñbmBS gm°Q>©a ì`y _| go ñbmBS H$mo H¡$go hQ>mE±Jo ({S>brQ>) ? 1
4. ñbmBS _| Am°{S>`mo H$mo H¡$go em{_b ({Z{dï>) H$a|Jo ? 1
5. CÚ{_Vm H$s Š`m ~mYmE± h¢ ? 1
6. Adeof Ý`yZrH$aU (~oH$ma KQ>m¡Vr) _| J«rZ Om°~ Š`m h¢ ? 1

{XE JE 5 àíZm| ‘| go {H$Ýht 3 àíZm| Ho$ CÎma Xr{OE & à˶oH$ àíZ 2 A§H$ H$m h¡ & 23=6
7. àñVw{V ~ZmZo _| à`wº$ {H$Ýht Xmo gm°âQ>do`am| Ho$ Zm_ {b{IE & 2
8. ñbmBS>emo H$mo Mmby H$aZo Ho$ {H$Ýht Xmo VarH$m| Ho$ Zm_ {b{IE &$ 2
9. gm_mÝ` CÚ_r j_VmE± Š`m h¢ ? 2
10. {ZU©`U Ho$ gmonmZ g_PmBE & 2
11. Ob g§ajU _| J«rZ Om°~ Š`m h¢ ? 2

.351 2

General Instructions :
Read the following instructions very carefully and strictly follow them :
(a) This question paper consists of two parts viz. Section A : Employability
Skills and Section B : Subject Skills.
(b) Section A : Employability Skills (10 Marks)
(i) Answer any 4 questions out of the given 6 questions of 1 mark each.
(ii) Answer any 3 questions out of the given 5 questions of 2 marks each.
(c) Section B : Subject Skills (50 Marks)
(i) Answer any 10 questions out of the given 12 questions of 1 mark each.
(ii) Answer any 5 questions from the given 7 questions of 2 marks each.
(iii) Answer any 5 questions from the given 7 questions of 3 marks each.
(iv) Answer any 3 questions from the given 5 questions of 5 marks each.
(d) This question paper contains 42 questions out of which 30 questions are to
be answered.
(e) All questions of a particular part/section must be attempted in the correct
order.
(f) The maximum time allowed is 3 hours.

SECTION A
(Employability Skills) (10 Marks)

Answer any 4 questions out of the given 6 questions of 1 mark each. 14=4
1. What are communication skills ? 1
2. What do you mean by a slide ? 1
3. How can you delete the slides in a Slide Sorter View ? 1
4. How can you insert an audio in a slide ? 1
5. What are the barriers to Entrepreneurship ? 1
6. What are the Green jobs in Waste Reduction ? 1
Attempt any 3 questions out of given 5 questions of 2 marks each. 23=6
7. Name any two softwares used for creating a presentation. 2
8. Name any two ways to run a slideshow. 2
9. What are the common entrepreneurial competencies ? 2
10. Explain the steps in decision-making. 2
11. What are the Green jobs in Water Conservation ? 2

.351 3 P.T.O.

IÊS> I
({df¶ H$m¡eb) (50 A§H$)
{XE JE 12 àíZm| ‘| go {H$Ýht 10 àíZm| Ho$ CÎma Xr{OE & à˶oH$ àíZ 1 A§H$ H$m h¡ & 110=10

12. AmЩVm H$s _mÌm ~Xbo {~Zm D$î_m àXmZ H$aZo H$s à{H«$`m __________ H$hbmVr h¡ & 1

13. __________ D$î_m hñVm§VaU H$m EH$ gmYZ hmoVm h¡ & 1

14. dm`w {dVaU H$aVo g_` dm`w Ho$ Vmn_mZ _| __________ {S>J«r go A{YH$ ~Xbmd Zht hmoZo
XoZm Mm{hE & 1

15. àerVZ àUmbr _| g§nr{S>V (H$åàoñS>) J¡g {Og Ad`d Ûmam R>§S>r H$s OmVr h¡, Cgo
___________ H$hVo h¢ & 1

16. àerVZ àUmbr _| Ohm± Vab ao{\«$Oa|Q> dmîn _| ~XbVm h¡, dh Ad`d _____ H$hbmVm h¡ & 1

17. {ZåZ{b{IV _| go H$m¡Z-gm EH$ {dñVma `§Ì Zht h¡ ? 1
(a) H¡${nboar Zbr
(b) âbmoQ> dmëd
(c) gmoboZm°`S> dmëd
18. {H$g YmVw Ho$ gmW A_mo{Z`m J¡g H$mo à`moJ _| Zht bmZm Mm{hE ? 1
19. _moQ>am| H$mo Mmby H$aZo Ho$ {bE {H$g `§Ì H$mo à`moJ _| bm`m OmVm h¡ ? 1
20. àerVZ àUmbr _| {H$gr EH$ gwajm `§Ì H$m Zm_ {b{IE & 1
21. EH$ em°qnJ _m°b Ho$ {bE Amn {H$g àH$ma H$s dmVmZwHy$bZ àUmbr H$m gwPmd X|Jo ? 1
22. {I‹S>H$s _| bJZo dmbo E`a-H§$S>reZa àm`: {H$g j_Vm Ho$ hmoVo h¢ ? 1
23. J¡g brH$ H$mo Om±MZo H$s H$moB© {d{Y ~VmBE & 1

{XE JE 7 àíZm| ‘| go {H$Ýht 5 àíZm| Ho$ CÎma Xr{OE & à˶oH$ àíZ 2 A§H$ H$m h¡ & 25=10
24. Eo{S>`m~o{Q>H$ øy{_{S>{\$Ho$eZ Ûmam R>§S>m {H$`m OmZm Š`m hmoVm h¡ ? 2

25. g|{g~b D$î_m àm{ßV H$s ì`m»`m H$s{OE & 2

26. dmVmZwHy${bV ñWmZ _| dm`w {dVaU H$s H$moB© EH$ {d{Y ~VmBE & 2

27. àerVZ àUmbr _| à`wº$ {H$Ýht Xmo àH$ma Ho$ H§$S>oÝgam| Ho$ Zm_ ~VmBE & 2

.351 4

SECTION B
(Subject Skills) (50 Marks)

Answer any 10 questions out of the given 12 questions of 1 mark each. 110=10

12. The process involving heating without changing the moisture content is
called ___________ . 1

13. ____________ is one of the modes of heat transfer. 1

14. While distributing air, temperature variation of more than _________
degrees should not be allowed. 1

15. In a refrigeration system, the component which cools the compressed gas
is called ____________ . 1

16. In a refrigeration system, the component where liquid refrigerant
converts into vapour is called __________ . 1

17. Which of the following is not an expansion device ? 1
(a) Capillary tube
(b) Float valve
(c) Solenoid valve
18. With which metal should ammonia gas not be used ? 1
19. Which device is used to start the motors ? 1
20. Name any one safety device in a refrigeration system. 1
21. Which type of air-conditioning system would you suggest for a shopping
mall ? 1
22. In which capacities are window type air-conditioners commonly available ? 1
23. Give any method of detection of gas leakage. 1
Answer any 5 questions out of the given 7 questions of 2 marks each. 25=10

24. What is cooling with adiabatic humidification ? 2

25. Explain sensible heat gain. 2

26. Give any one method of air distribution in an air-conditioned space. 2

27. Give any two types of condensers used in a refrigeration system. 2

.351 5 P.T.O.

28. EH$ Kaoby ao{\«$OaoQ>a _| {H$g àH$ma H$m Bd¡nmoaoQ>a à`moJ _| bm`m OmVm h¡ ? 2

29. {H$Ýht Xmo ao{\«$Oa|Q {Z`§ÌU `§Ìm| Ho$ Zm_ {b{IE &> 2

30. g¡Ho$ÝS>ar ao{\«$Oa|Q²>g Ho$ AZwà`moJ ~VmBE & 2

{XE JE 7 àíZm| ‘| go {H$Ýht 5 àíZm| Ho$ CÎma Xr{OE & à˶oH$ àíZ 3 A§H$ H$m h¡ & 35=15

31. S>røy{_{S>{\$Ho$eZ g{hV erVbZ H$s à{H«$`m H$s ì`m»`m H$s{OE & 3
32. Hy$qbJ bmoS> go Amn Š`m g_PVo h¢ ? 3

33. ao{S>`b n¡ar_rQ>a àH$ma H$s S>ŠQ²>g Ûmam dm`w {dVaU H$s ì`dñWm ~VmBE & 3

34. dm`w Ûmam R>§So> {H$E OmZo dmbo H§$S>oÝgam| H$mo h_ H$hm± à`moJ _| bmVo h¢ ? 3

35. âb{S>S> àH$ma Ho$ Bd¡nmoaoQ>a _| Š`m {deof hmoVm h¡ ? 3

36. EŠMwEqQ>J (àdV©H$) VWm gwJ«mhr VÎdm| _| A§Va ñnîQ> H$s{OE & 3

37. R11 àH$ma Ho$ ao{\«$Oa|Q Ho$ bm^ ~VmBE & 3

{XE JE 5 àíZm| ‘| go {H$Ýht 3 àíZm| Ho$ CÎma Xr{OE & à˶oH$ àíZ 5 A§H$ H$m h¡ & 53=15

38. dmVmZwHy$bZ àUmbr _| _mZd gw{dYm H$mo à^m{dV H$aZo dmbo H$maH$m| H$s ì`m»`m H$s{OE & 5

39. {H$gr dmVmZwHy${bV ñWmZ Ho$ {bE dmVmZwHy${bV dm`w ^oOZo Ho$ {bE {d{^Þ àUm{b`m| H$s
ì`m»`m H$s{OE & 5
40. àerVZ àUmbr _| H§$S>oÝga H$m H$m`© g_PmBE & 5
41. S>r\«$mopñQ>¨J Š`m hmoVr h¡ ? BgH$s {d{^Þ {d{Y`m| H$s ì`m»`m H$s{OE & 5
42. âbwAmoamoH$m~©Ýg H$s H$m¡Z-gr {deofVmE± BÝh| ao{\«$Oa|Q Ho$ ê$n _| Cn`wº$ ~ZmVr h¢ ? 5

.351 6

28. Which type of evaporator is used in a domestic refrigerator ? 2

29. Name any two refrigerant control devices. 2

30. Give applications of secondary refrigerants. 2

Answer any 5 questions out of the given 7 questions of 3 marks each.

31. Explain the process of cooling with dehumidification. 3

32. What do you understand by cooling load ? 3

33. Give the arrangement of air distribution through radial perimeter type of
ducts. 3

34. Where do we use air-cooled condensers ? 3

35. What is special in a flooded type evaporator ? 3

36. Distinguish between actuating and sensing elements. 3

37. Give advantages of R11 type of refrigerant. 3

Answer any 3 questions out of the given 5 questions of 5 marks each.

38. Explain the factors affecting human comfort in an air-conditioning
system. 5

39. Explain various systems of feeding conditioned air in an air-conditioned
space. 5

40. Explain the function of a condenser in a refrigeration system. 5

41. What is defrosting ? Explain its various methods. 5

42. What properties of fluorocarbons make them suitable as a refrigerant ? 5

.351 7 P.T.O.