flow and return reversed

[raymcc]

Hi all, I have just discovered after 10 years , that the flow and return on my trusty worcester bosch boiler , are reversed. Quick fix is to set the boiler stat to 8 o'clock position and set the pump to max ie not auto. The 3 port valve is working correctly, hot water comes in at the bottom and is diverted to rads or hot water tank. I wonder if I could just reverse the pump, that would mean the 3 port valve sucking instead of blowing.

 

[ianmcd]

The 3 port valve is working correctly, hot water comes in at the bottom and is diverted

Then the flow and return are correct , what makes you think they are reversed ?

 

[raymcc]

easy,just feel the pipes, the return is hotter than the flow. Also boiler stat has to be held at 8 oclock

 

[ianmcd]

easy,just feel the pipes, the return is hotter than the flow. Also boiler stat has to be held at 8 oclock

are you feeling these pipes straight from the boiler ? or where are you feeling them ?

 

[raymcc]

as they exit the boiler

 

[vulcancontinental]

are you feeling these pipes straight from the boiler ? or where are you feeling them ?

and when? If you turn the system ON the return from the cylinder which may be up to temperature will be hotter for a while than the flow from the boiler.

 

[ianmcd]

as they exit the boiler

Sorry but you are wrong , the boiler doesnt know what pipes are attached, it is common to have wrong orioentation, but the flow from the boiler will always be hotter than the return, whether that flow is actually connected to the system return is a different thing, but if the return is hotter than the flow then most boilers wont work, you said the AB port of the 3 port valve is the hottest and distributes the heat to whatever demand, this means the flow is correct, post pics of what you have because what you are saying makes no sense

 

[sjmac]

Tbf, I fitted an Ri 10 years ago and balls up the f and r. Customer is a landlord and complete **** and I go back every year - its works just fine, no issues in 10 years. If he had been a decent guy I would have swapped over at my expense

 

[raymcc]

Its easy to check that the boiler is reverse plumbed, you can identify the flow and return from the manufacturers instrctions. What should be the return is consistently hotter than the flow. Problem arises becase the boiler thermostat is now on the water flowing into the boiler. So the water flowing out of the boiler gets hotter and hotter until the water flowing in to the boiler is ay the desired temperature. The boiler thermostat has to be set very low like at the 8 oclock position, other wise the boiler overheats and shuts down. Original question was whether I could turn the pump upside down. But I am inclined to think if it ain't bust dont fix it.

 

[ianmcd]

if you turn the pump direction then your 3 port valve wont work properly