Odd y plan.

[PhoenixServices]

I supposes you would call it a y plan. Changed the heating pump on it last night as it has been pumping over so bad with cold feed on flow and vent on return it had killed it. Going to change the cf and vent positions on Saturday. But instead of a mid position valve it has a second pump on the return of the cylinder.

Secondly the heating pump only gets a live when hot water is selected on the programmer. Customer thinks it's been like this since the house was put in.
So two questions

Any ideas how to rewire this so they can have them separately.? its a potterton profile boiler, and centaur 2 channel programmer.

Secondly will putting the cf and vent in the normal position by the heating pump be ok or will it still pump over.
Trying to swing the customer to put in 3-port or 2-2 ports, but they arn't keen.

 

[stevetheplumber]

sounds like it was gravity and been chopped around hence the heating only working with the hot water i would change cf and vent to close coupled and then tee to each pump run both channels via respective stats to run pumps but only fire boiler from hot water channel leave programmer in gravity mode youll still have to select both to fire boiler but hot water stat will cut pump at temperturte
to be honest after typing that probably easier to do it properly

 

[PhoenixServices]

Cheers Steve. I like your thinking, I'm hoping they go for the latter option.

 

[PhoenixServices]

Did this job Saturday, changed the last 2 rads that hadn't pinholed. Then changed the cf and vent to 22mm off the heating pump. It was already close coupled in the loft but had 2 cold feeds about 1ft apart. So ditched one. put cleaner in it then going to mains flush and look at the wiring.

And I got the wrong info, it's wired so you can only have hw with heating, so need to look at that.

 

[Whyme]

As steve said its a ragged around gravity system, Tell them you can make it work in a fashion but the cost of sorting it properly against future aggro will be minimal.