Symptom: Inaccurate Temperature Control - Daikin altherma 3 M Service Manual

2 | Troubleshooting
Possible failure
3‑way valve blocked.
Possible failure
Water circuit – requested
capacity too high.
Water circuit - water
volume too big.
Water circuit - pressure
drop too big.

2.4.12 Symptom: Inaccurate temperature control

Possible failure
Incorrect setting of unit
control method (setting
[C‑07]).
Incorrect setting of pump
operation mode
(continuous, sample,
request) (setting [F‑0D]).
Possible failure
User interface –
thermostat sensor value
NOT representing room
temperature.
Service manual
80
Root cause category: component – electrical
Root cause
Component failure.
Root cause category: system design
Root cause
Incorrect system selection. Check required capacity by
▪ Long water piping,
▪ Too many heating
emitters.
▪ Too small water piping,
▪ Too long water piping,
▪ Too many heating
emitters.
Root cause category: parameter (setting)
Root cause
Incorrect setting of unit
control method (setting
[C‑07]) (leaving water
control, room thermostat
control, ext. room
thermostat control).
Incorrect setting.
Root cause category: installation
Root cause
Bad location of thermostat
sensor (external influence)
in case of room thermostat
control (setting [C‑07]=2).
Check
Check the 3‑way valve.
Check
heat load calculation. See
the capacity tables in the
engineering data book to
know max. system capacity
at indicated conditions.
Check required capacity by
heat load calculation. See
the capacity tables in the
engineering data book to
know max. system capacity
at indicated conditions.
Compare the pressure
drop of the total system
with the water pump
characteristics (See check
of water pump). Decreased
water flow will cause a
drop in capacity.
Check
Check if setting [C‑07]
(leaving water control,
room thermostat control,
ext. room thermostat
control) is set according to
the application.
Confirm setting [F‑0].
Check
Check if user interface is
mounted in the correct
position to measure the
correct room temperature.
Repair
Replace the 3‑way valve.
Repair
Adapt system design.
Adapt system design.
Adapt system design.
Repair
Adjust setting to match
application.
Adjust setting [F‑0] if
required. (Factory setting:
[F‑0]=1).
Repair
Correct the position of the
user interface for more
accurate room
temperature
measurement.
EBLA09~16DA + EDLA09~16DA
Daikin Altherma 3 M
ESIE20-06A – 2021.03