Urgent !HELP! - Pump replaced correct way round ?

[BRADSPAU]

Hi. I have recently replaced my central heating pump with a grundfos alpha. since doing so, my rads are getting nice and warm but the hot water only ever gets luke warm, no matter how long I have had the water timer switched on. I have a conventional bolier, fully pumped system with 3 port valve, and thermostat on the hot water cylinder set about 70 degrees.

My question is, if I have put the pump on the wrong way round, would this cause the above problems. The pump sits on the pipe from the cold water tank then branches off to the 3 port valve and hot water cylinder.

The pumps flow arrow is pointing down away from the pipe that is attached to the water tank. I foolishly did not note the orientation of the old pump before removing it !.

 

[ChrisR]

Depends where the boiler is! It should pump from the boiler towards the valves.

 

[BRADSPAU]

boiler is in the kitchen and pump is in the loft space

 

[EliteHeat]

boiler is in the kitchen and pump is in the loft space

 

[baxpoti]

If it is all going in reverse and the heating is OK, the hot water should still be OK.
Boilers tend to overheat if the flow is reversed as the sensors are on the flow pipe.
I would imagine it's your 3 port valve that's at fault.

 

[BRADSPAU]

3 port valve was only replaced last year. valve is moving when thermosat calls for heat / water

 

[Saveme22]

Airlock in primary circuit?

 

[ChrisR]

Airlock in primary circuit?

Well done - easy to get distracted by someone's suggestion. Yours is the first question to be asked!

Vent at "V"

 

[BRADSPAU]

hi. i think ive seen the vent, just a knurled nut. do i just open it and wait for air to escape?. heating on or off while doing this ?

 

[BRADSPAU]

.j

 

[gas4you]

Heating off and just loosen it until water comes out.

 

[BRADSPAU]

Airlock was the culprit. Loosened the vent screw above the hot water cylinder and a large gush off air came out. Water is now piping hot again.

Many thanks to all that replied