Apprentice plumber help

[Al-Glasgow]

Hi

I have a problem with a friends back boiler system.
I am on Level 2 plumbing course, keen to get level 3 started in summer.

No heat from radiators, hot water ok, immerser switch heating cylinder ok.

He tells me that usually they have had the pump replaced 2 years ago.(behind gas fire, area of back boiler)

All suggestions where to start on Diagnosis would be appreciated.

Alan

 

[JPC]

have u checked the pump?
any zone/diverter valves? are they working ?

 

[ChrisR]

Check auto or manual air vent by HW cylinder, or anywhere else air could get trapped.

 

[chrishutt]

Look in the sticky reference topic near the top of the topic list. Lots of info.