13 fault finding, Fault finding – Grant Products HPAW155 User Manual
Page 42
Temperature
Resistance
Temperature
Resistance
Temperature
Resistance
Temperature
Resistance
˚C
k
W
˚C
k
W
˚C
k
W
˚C
k
W
-20
37.4111
2
13.0055
24
5.1978
46
2.3276
-19
35.5384
3
12.4391
25
5.0000
47
2.2493
-18
33.7705
4
11.9008
26
4.8109
48
2.1740
-17
31.1009
5
11.3890
27
4.6300
49
2.1017
-16
30.5237
6
10.9023
28
4.4569
50
2.0320
-15
29.0333
7
10.4393
29
4.2912
51
1.9651
-14
27.6246
8
9.9987
30
4.1327
52
1.9007
-13
26.2927
9
9.5794
31
3.9808
53
1.8387
-12
25.0330
10
9.1801
32
3.8354
54
1.7790
-11
23.8412
11
8.7999
33
3.6961
55
1.7216
-10
22.7133
12
8.4377
34
3.5626
56
1.6663
-9
21.6456
13
8.0925
35
3.4346
57
1.6131
-8
20.6345
14
7.7635
36
3.3120
58
1.5618
-7
19.6768
15
7.4498
37
3.1943
59
1.5123
-6
18.7693
16
7.1506
38
3.0815
60
1.4647
-5
17.9092
17
6.8652
39
2.9733
61
1.4188
-4
17.0937
18
6.5928
40
2.8694
62
1.3746
-3
16.3203
19
6.3328
41
2.7697
63
1.3319
-2
15.5866
20
6.0846
42
2.6740
64
1.2908
-1
14.8903
21
5.8475
43
2.5821
65
1.2511
0
14.2293
22
5.6210
44
2.4939
66
1.2128
1
13.6017
23
5.4046
45
2.4091
ATC
38
Fault Finding
13 Fault Finding
5. When tracing a fault code, use the
table of fault codes on page 32 to
help you. As often as not, it will be
a wire that has become loose or
disconnected. Check all wires for
security before calling our helpline
for assistance. There are 6 sensors
in total. The ATC have black tails
and the BTC have blue tails. The
resistance/temperature tables for
the ATC and BTC sensors are given
in Figures 13-2 and 13-3.
6. The pressure gauge on the side of
the heat pump measures refrigerant
pressure not water pressure and is
a useful tool to help fault finding.
If the heat pump goes out on high
pressure, it will almost certainly be
as a result of an air-lock. An air-lock
that cannot be cleared by the pump
will have the same effect as that of
an ordinary boiler. It will overheat as
it cannot get rid of the heat it is
producing. This will be evident if,
when switched on from cold or
warm, the gauge rises quickly
towards the yellow or red zones. If
this happens, switch off, and purge
the system. (Remember to check
the circulating pump is working.)
In normal working conditions, the
pointer on the gauge will remain in
the green zone.
7. Capacitors store an electrical
charge. Small capacitors are found
in all domestic electronics and
cause no danger. However, the
capacitors in a heat pump are
power capacitors and will give a
large electric shock if care is not
taken. DO NOT try to test the
functionality of a capacitor using a
screwdriver or multi-meter and
NEVER try to short out the
connections – even with the mains
voltage removed. Seek the help of a
qualified electrician or a qualified
heating engineer who has been
trained by Grant Engineering.
8. This is a repeat of note 5.
If the heat pump goes out on high
pressure, it will almost certainly be
as a result of an air-lock. An air-lock
that cannot be cleared by the pump
will have the same effect as that of
an ordinary boiler. It will overheat as
it cannot get rid of the heat it is
producing. This will be evident if,
when switched on from cold or
warm, the gauge rises quickly
towards the yellow or red zones. If
this happens, switch off, and purge
the system. (Remember to check
the circulating pump is working.)
Figure 13-2: ATC sensor resistance table