Fault Diagnosis - Mira Montpellier Installation, Operation, Maintenance Manual

Symptom
1. Only hot or cold
water from mixer
outlet.
2. Fluctuating or
reduced flow rate.
3. No flow rate from
mixer outlet.
4. Blend temperature
drift.
5. Maximum blend
temperature setting
too hot or too cold.

FAULT DIAGNOSIS

Cause/Rectification
a. Inlet supplies reversed (hot supply to cold
supply).
b. No hot or cold water reaching mixer.
c. Check strainers and inlet/outlet fittings for
blockage.
d. Installation conditions continuously
outside operating parameters: refer to
SPECIFICATION, and 2.e. below.
Normal function of the thermostatic control when
operating conditions are unsatisfactory;
a. Check strainers and inlet/outlet fittings for
blockage.
b. Make sure minimum flow rate is sufficient
for supply conditions.
c. Make sure the maintained inlet pressures
are nominally balanced and sufficient.
d. Make sure the inlet temperatures
differentials are sufficient.
e. (Subsequent to rectification of supply
conditions) Check thermostatic
performance; renew Piston Assembly if
necessary.
a. Check strainers and inlet/outlet fittings for
blockage.
b. Hot or cold supply failure.
Indicates operating conditions changed.
a. Refer to symptom 2. above.
b. Hot supply temperature fluctuation.
c. Supply pressures fluctuating.
d. Seal damage or wear. Renew seals.
a. Indicates incorrect maximum temperature
setting; refer to COMMISSIONING
section.
b. As symptom 4. above.
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