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Maintenance and Service

Exam revision materials for Plumbing Level 2&3 and ACS Gas Safety test

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Thermal Store Cylinders


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HUB-001A-WAX Vado Thermostatic Cartridge


Hudson Reed




S960134NU Thermostatic Cartridge

Sirrus Rothwell R995 Antique Shower








Alfa Laval






Electroheat PLC





Heat Lline








Saunier Duval


Viessmann Vitodens 100 W Compact



Space Heaters




Armitage Shanks





Bathstore Thermostatic Cartridge

Servicing Guide



Thermal Store Cylinders


Underfloor Heating





Hot Water Cylinders




Gas Safety Inspection

Gas Flue Analysers

Gas Hobs



Pulsacoil 2000 - faulty T1 thermistor GT153

Pulsacoil 2000 produces no hot water.

  • The water tank is full and the cylinder is hot
  • The PCB flushes twice indicating a normal operation
  • To test open the hot water tap and measure the voltage to the pump
  • If there is no voltage replace the Thermistor T1
  • The part number is Gledhill GT153
< Go Back2016-04-29

Pulsacoil A-class - Burnt relay and base

Not enough or now hot water

PC2000 Relay Base (New style - Must change relay as well)

Relay base code on our website xb147

Relay          code on our website xb146

Info - Berhams <info@berhams.co.uk>

< Go Back2016-03-25

Pulsacoil 3 - faulty pump replacement - Grundfos 15/50 Pump for Gledhill Units XB004

Pulsacoil 3 - hot water is intermittent or no hot water while the clinder itsekf is hot.

  • Hot water goes cold after 5min shower
  • Hot water becomes lukewarm when tap is opened on full
  • To test unscrew the vent cup on the pump and with hot water running on full try to stop the impeller with a screw driver
  • If the impeller is easy to stop then pump is faulty and needs replacement the replacement part is Grundfos 15/50 Pump for Gledhill Units XB004
< Go Back2015-07-08

Pulsacoil A-class APA4200 - faulty Gledhill MIP098 Relay Retro Fit Kit

Pulsacoil A-class APA4200 bottom (off peak) immersion heater doesn't work

  • The external power is checked and presents
  • Check the right hand side relay for burner marks
  • Turn the off-peak immersion heater on and check the voltage between blue and brown at the relay
  • If no 240V then replace the part
  • The part number is: Gledhill MIP098 Relay Retro Fit Kit
< Go Back2014-11-08

Pulsacoil 2000 - Gledhill GT153 Boilermate/Systemate/ Gulfstream Hot water Sensor replacement

Temperature fluctuates between hot and cold from the hot water tap or water is constantly cold while the cylinder is hot

  • One of the reasons for that is a faulty Hot water sensor
  • To replace the part you need to isolate the mains water and electrical supplies to the cylinder 
  • Open a hot water tap to remove pressure from the hot water pipe
  • Unscrew the Hot water sensor from the top pipe pocket
  • Put PTFE tape on a new Hot water sensor before assembling to make a water tight connection
  • The part number is Gledhill GT153 Boilermate/Systemate/ Gulfstream Hot water Sensor


< Go Back2014-10-03

Pulsacoil A-Class - 4 Pin overheat sensor GT199 replacement

Thermal-store Pulsacoil A-Class doesn't produce any hot water. The red light on a front panel is constantly flashing. Resetting the unit doesn't help for a long time

  • Check the top pocket where the overheating sensor is sitting. 
  • Remove the sensor and check if there is any water inside te pocket
  • If there is some water then replace 4 Pin overheat sensor GT199 
  • Water in the pocket indicates that the cylinder is leaking due to corrosion
  • Before replacing the sensor add Central heating leak sealer into the unit to stop the leak
  • If sealing chemicals don't help then cylinder will have to be replaced
< Go Back2014-08-29

Pulsacoil 2000 - Pulsa Coil 2000 PCB GT152 replacement

Thermal store Pulsacoil 2000 - water fluctuates from cold to worm when water in the cylinder is hot

  • Red light indicator flushing without pause when hot water tap is opened
  • Remove thermistors T1 and T2 from the pockets and check hot water
  • If no change then replace the PCB
  • The part number for replacement is Pulsa Coil 2000 & Pulsa Coil 3 PCB GT152
< Go Back2014-07-07

Pulsacoil 3 - Gledhill Relay XB321 replacement

Thermal-store Cylinder Pulsacoil 3 - doesn't produce any hot water

  • The pump is running
  • There is power supply to the unit itself 
  • There is no power coming to the both immersion heaters
  • Check the water level or a float switch in the header tank
  • Check that that the overheat stat hasn't triggered
  • Replace the Gledhill Relay XB321

PDF - Pulsacoil 3 - Gledhill Relay XB321 replacement - installation instructions

< Go Back2014-06-30

Pulsacoil 2000 - Grundfos 15/50 Pump XB004 replacement

Pulsacoil 2000 - no hot water but the cylinder is full of hot water

< Go Back2014-03-21

Pulsacoil A-CLASS APA4180 - Faulty OMRON RELAY & BASE XB298

Pulsacoil A-CLASS APA4180 - Both immersion heaters dont't work

< Go Back2014-03-04

Pulsacoil 2000 - Hot water temperature flactuation

Pulsacoil 2000 - Hot water temperature fluctuation from hot to warm/cold

  • Remove a bottom Thermistor from the dry pocket 
  • Open a hot water tap and check if a temperature fluctuation has stopped
  • If its stopped then replace the Thermistor
  • The part number is Gledhill GT147, GT149 
< Go Back2014-01-26

Pulsacoil 2000 Electric Thermal Store - boiling hot, condensation on the ceiling

Pulsacoil 2000 Electric Thermal Store - water boiling hot inside the cylinder, a lot of condensation on the ceiling.

< Go Back2013-10-19

Pulsacoil III - intermittent hot water

Storage heater Pulsacoil 3 - intermittent hot water. Open a hot water tap and if hot water is intermittent then we need to test the pump. First of all the Pulsacoil pump produced by Gredhill and designed to work on voltages between 60 - 240V depends on water temperature. The old pumps could be red-coloured with a part number 59525645 written on them. All new pumps are grey. With hot tap opened check the voltage to the pump with a multimeter if it's outside this range then the PCB is faulty. Also look at the light on the PCB the normal operation is when flushing at low frequency. If not then thermistors one and two might need replacement. To check the pump with electrical supply off measure resistance between the live and neutral it should be 175 Ohms. If considerably higher or lower then pump to be replaced. For more information call Pulsacoil technical helpline Tel.: 09066 110 005

Pulsacoil III pump: The part number for replacement is XB004 and you can order it from here.

Pulsacoil III manual: PDF

< Go Back2013-05-01

Pulsacoil 2000 - Electric Thermal Store

Electric Thermal Store Pulsacoil 2000 doesn't produce any hot water. No hot water coming from any tap in the property. We are making several checks first. Check fuses and electrical supply to the boiler. Check that the header tank is half full with water, if water is at the very bottom then top it up and check performance. Switch it on, open a hot water tap. Is plate heat exchanger getting hot?

  1. If the plate heat exchanger is cool then we need to check the immersion heaters and thermostats. Isolate the electrical supply, put thermostat target temperature on maximum and check for continuity between "in" and "out". If now continuity the thermostat have to be replaced.
  2. The rod thermostat (7") part number is XB003/XB081. You can order it from here.

Boiler manual: PDF

< Go Back2013-03-15