Andrews Water Heaters logo

Built to perform

  • Features and benefits
  • Specifications
  • Literature
  • Case studies
  • BIM
  • CAD
  • Error codes
  • Energy labelling
  • Up to four modulating burners
  • Recovery rates of up to 1920 litres of hot water per hour
  • 98% gross efficiency
  • Fully automatic electronic control with Building Management System (BMS) interface as standard
  • Built-in high temperature anti-legionella program
  • Energy Technology Listed
  • The optimum amount of gas is used to maximise energy efficiency, cost savings and built-in redundancy for outputs of 60kW and above
  • Ensures continuous supply of hot water and can satisfy the most demanding hot water applications
  • Energy efficient, cost effective operation
  • Easy integration into the Building Management System
  • Safety and protection against legionella
  • Complies with the Water Supply (Water Fittings) Regulations and Scottish Byelaws and qualifies for the Government Enhanced Capital Allowance scheme

View product specification

When clicked this will open the product specification in PDF format.


30/200 60/200 90/200 120/200
    30/300 60/300 90/300 120/300
Heat input (gross) kW 31.1  62.2 93.3 124.4
Heat output kW 30 60 91 122
Gross thermal-efficiency % 98 98 98 98
Standby heat loss mj/month 780 780 780 780
 NOx emissions (0% 02)  mg/kWh  44  44  44  44
NOx emissions (0% 02) ppm 25 25 25 25
 ErP efficiency rating    A  A  A
Gas data
Gas flow rate (natural gas) m3/h 2.96 5.93 8.89 11.85
Gas flow rate (propane) m3/h


4.35 6.53 8.71
Storage capacity Litre 200/300 200/300 200/300 200/300
Recovery rate at 50ºC rise Litre/hr 480 960 1440 1920
Recovery rate at 56ºC rise Litre/hr 429 857 1286 1714
Operating pressure (unvented) bar 3.5 3.5 3.5 3.5
Minimum working pressure bar 1 1 1 1
Maximum pressure bar 6 6 6 6
Fuse rating amp 5 5 5 5
Electrical power consumption W 170 340 510 680
Noise level dBA 51 51 51 51
Weight full (200 litre) kg 355 370 385 400
Weight full (300 litre) kg 465 480 495 513
Weight empty (200 litre) kg 155 170 185 200
Weight empty (300 litre) kg 165 180 195 210
Max. flue run (concentric) m 14 12  14  14 
Max. flue run (conventional) m 50 20 50  40
Flue diameter mm 80/125 80/125 130/200 130/200
Width mm 602 602 602 602
Depth mm 932 932 932 932
Height mm 1528/1952 1528/1952 1528/1952 1528/1952
Front service clearance mm 1000 1000 1000 1000
Side service clearance mm 300 300 300 300
Clearance above heater mm 500 500 500 500

Find out more about the MAXXflo in action by reading our case studies.

New multi level BIM files now available for this product

Download your Building Information Modeling (BIM) object(s) for this product.

Download CAD files for this product using the links below. To access CAD files you will need the correct software installed to allow you to open .dwg files such as AutoCAD.

Feel free to call our technical helpline on 0345 070 1055 if you need any support.

Master Board Blocking Codes

E09 Control Error: Internal RAM location not correct
E12 Control Error: The incorrect parameters are programmed in the slave board
E13, E15 Control Error: A references measurement indicated that the AD-circuit is defective, too low
E14, E16 Control Error: A references measurement indicated that the AD-circuit is defective, too high
E18 Control Error: Internal RAM
E19 Control Error: Not able to read parameters
E20 No slave board present
E22 Power Fault: The 50Hz has too large deviation
E60 Tank sensor opened circuit
E65 Return sensor opened circuit
E70 Tank sensor shorted
E75 Return sensor shorted

Slave Board Blocking Codes

E0 Read Error: Not able to read stored parameters
E28, E29, E30, E31 Control error: Reference measurements indicates that there is an error in the AD circuit
E33 Flame detected when gas valve was closed
E41 Phase Error: Live and neutral reversed
E42 Phase Error: Too much deviation in the supply voltage frequency
E44 Control Error: Poor communication between the two processors
E47 Return sensor open circuit
E48 Flow sensor open circuit
E63 Return sensor short circuit
E64 Flow sensor short circuit
E78 Reset Error: Too many user resets

Slave Board Lockout Codes

A01 Three Failed Ignitions: After three ignitions, there was still no flame detected
A02 Overheat Stat Failure: No water flow conditions, the flow sensor is not detecting a temperature increase during operation
A03 The two flow sensors have too greater temperature differential between them, 10°C for more than 60 seconds
A05 Gas Valve Relay Error: The gas valve relay is not switching correctly
A06 Safety Relay Error: The safety relay is not switching correctly
A08 Fan Error: The fan is not reaching its target value or speed for more than 60 seconds
A09 Control Error: Internal storage location
A10 The contents of the stored parameters are not correct
A11 Flow Temperature: Flow temperature went above 95°C
A12 Control Error: The stored contents inside the control are not matching the software version
A14, A15, A16, A17, A19 Control Error: Internal storage location
A20 Flame detection after gas valve is closed. Flame still present 10 seconds after the gas valve is closed
A21 Flame detected before opening of the gas valve during the start up sequence
A24 Too many flame failures: When the flame fails three times within on burn cycle

The Energy Related Products Directive (ErP) has applied to all domestic and commercial heating and hot water products through Europe since September 2015.

From 26th September 2018 any water heater sold must have an efficiency/NOx output rating of C or above. All of our products are compliant the new ErP legislation. Read more about our product range, and legislation changes here.

FREE site survey