What does the Vaillant S.53 fault code mean?

Your boiler has temporarily stopped working because it cannot move water around your heating system fast enough, likely due to low pressure or a blockage.

How much does it cost to fix Vaillant error code S.53?

Typical repair cost for the Vaillant S.53 fault is £90-180 including labour.

Can I fix Vaillant fault code S.53 myself?

Check your boiler pressure gauge; if it is below 1.0 bar, use the filling loop to top it up to 1.5 bar

Vaillant S.53 Fault Code: What It Means & How to Fix It

What the manual says

Manufacturer manual

Appliance is within the waiting period of the operation block function due to water shortage (VL-RL spread too big)

From this model's manual

Verified against the Vaillant/Vaillant Ecotec Plus Pro 839592 05 2006 installation & service manual, page 43.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Find a Gas Safe engineer

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Boiler cover options

Avoid the next call-out bill

A cover plan would handle faults like S.53: no call-out fees, no surprise bills.

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Related fault codes

F.22View →F.75View →

All 135 fault codes on the ecoTEC pro 28

Seeing a different code? Every code this model can display, in one place.

35 96 con Connection D,11 D.0 D.1 D.2 D.3 D.4 D.5 D.7 D.8 D.9 D.10 D.12 D.13 D.17 D.18 D.20 D.22 D.23 D.25 D.27 D.28 D.30 D.33 D.34 D.35 D.40 D.41 D.44 D.47 D.50 D.51 D.60 D.61 D.64 D.65 D.67 D.68 D.69 D.70 D.71 D.72 D.75 D.76 D.77 D.78 D.80 D.81 D.82 D.83 D.84 D.90 D.91 D.93 D.96 D.97 F.0 F.1 F.10 F.11 F.13 F.20 F.22 F.23 F.24 F.25 F.27 F.28 F.29 F.32 F.49 F.61 F.62 F.63 F.64 F.65 F.67 F.70 F.71 F.72 F.73 F.74 F.75 F.76 F.77 F.78 F70 P.0 P.1 P.2 P.3 P.4 P.5 P.6 S. 2 S. 5 S.0 S.1 S.3 S.4 S.6 S.7 S.8 S.10 S.11 S.13 S.14 S.15 S.16 S.17 S.20 S.21 S.22 S.23 S.24 S.25 S.26 S.27 S.28 S.30 S.31 S.32 S.34 S.36 S.41 S.42 S.52 S.54 S.96 S.97 S.98

Your boiler has temporarily stopped working because it cannot move water around your heating system fast enough, likely due to low pressure or a blockage.

What the manual says

Engineer required

Avoid the next call-out bill

Related fault codes

All 135 fault codes on the ecoTEC pro 28

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