Hot Water Question Apollo Gas Boiler

[Caspar]

My mums got an old Apollo gas boiler which does the central heating ok but has never worked for hot water. She has used the immersion heater instead for hot water. She decided to get a plumber out to get the hot water to work and he said the pump was sticking. He apparently got it going but by time I went round it didn't work again. Surely the pump is used for both heating and hot water so if it works for one then it would work for both?
You can hear it running when the heating is on so it can't be the problem.
Any suggestions of what might be wrong? Thanks

 

[chrishutt]

We need to know what sort of system you have. Is it fully pumped? Does it use 1 motorised valve (Y plan) or 2 motorised valves (S plan) or 2 pumps (!!!!)?

 

[B.O.B DOLE]

My mums got an old Apollo gas boiler which does the central heating ok but has never worked for hot water. She has used the immersion heater instead for hot water. She decided to get a plumber out to get the hot water to work and he said the pump was sticking. He apparently got it going but by time I went round it didn't work again. Surely the pump is used for both heating and hot water so if it works for one then it would work for both?
You can hear it running when the heating is on so it can't be the problem.
Any suggestions of what might be wrong? Thanks

try replacing the 3 port valve

 

[namsag]

If the pump had gone on an apollo the boiler would sound like it was being hit with a hammer due to it being low water content copper heat exchanger