Reyds.Heat pumps · Boilers · Steam

Randburg · Same-day

Heat Pump Not Heating Water in Randburg

The unit runs but water stays cold or only reaches lukewarm temperatures. This page covers how we diagnose and repair it on heat pumps in Randburg.

This fault is normally treated as same-day work because the site has effectively lost hot water, steam or safe operation.

Large stock of 1970s–1990s homes with ageing 150–200 L geysers, plus a spread of small commercial and light industrial units along Malibongwe. Gauteng municipal water is moderately hard, so scale on elements and heat exchangers is the single most common cause of falling performance.

Area
Randburg, Johannesburg
Equipment
Heat pumps
Call
069 268 0988

What we find here

Likely causes

  • Low refrigerant charge from a slow leak
  • Failed compressor or start capacitor
  • Fouled evaporator restricting airflow
  • Faulty water temperature sensor holding the unit off
  • Reversing valve stuck in the wrong position

How it is confirmed

Diagnostic sequence

  • Measure suction and discharge pressures against ambient
  • Check compressor current draw versus nameplate
  • Verify sensor resistance against the manufacturer curve
  • Measure water delta-T across the condenser

FAQs

Frequently asked questions

What causes heat pump not heating water?

The usual causes are low refrigerant charge from a slow leak, failed compressor or start capacitor, fouled evaporator restricting airflow, faulty water temperature sensor holding the unit off. Which one it is can only be confirmed by measurement, not by symptom alone.

How do you diagnose it?

Measure suction and discharge pressures against ambient; Check compressor current draw versus nameplate; Verify sensor resistance against the manufacturer curve; Measure water delta-T across the condenser. The readings are recorded so the repair decision is based on data.

Can I keep using the system in the meantime?

No — isolate the plant and call 069 268 0988. Running it in this condition risks further damage or an unsafe situation.

Do you attend this fault in Randburg?

Yes. Technicians work out of the central Johannesburg base, which keeps travel time short for northern-suburb call-outs. Element and thermostat failures dominate domestic call-outs in this area.

Heat Pump Not Heating Water — Randburg

Element and thermostat failures dominate domestic call-outs in this area.