Heating not working with new radiators and pumps

JR1210

Having a bit of an issue getting the house warmed up. Its an old small 3 bed house, replaced all radiators, oil burner, back boiler at fireplace and pumps

I replaced the burner on the boiler to a new Reilo one, replaced the water pump to a new 25-60 130 Grundfos pump.. Replaced the backboiler and put a new Grundfos 25-50 130 pump at the back boiler
Now when I stick on the heating the water doesnt heat the radiators (all 7 radiators have been replaced and air removed)
The boiler pump works but not circulating right. If I stick on the pump at the back boiler and have 2 pumps going it warms the raidators and after a while will come out the overflow in the attic

The only thing I remember there was a one way valve at the back boiler which the plumber took out whenever he replaced the back boiler fireplace, he said it wasnt needed
Could the removal of the one way valve be upsetting the apple cart?

K.Flyer

A couple of quick questions;
How long ago since the work was done?
Did you do all the work, or did you have a Plumbing / Heating contractor in to do it?
If it was a contractor, why have you not got them back in to sort it out?

JR1210

A builder drained the system and changed the radiators, I changed the pumps and a plumber plumbed in the back boiler as it was not a straight connection. I dont have the number of the plumber anymore

The plumber took out the non return valve which was in front of the pump at the back boiler (Fireplace). He said it wasnt required, but obviously it was there to serve a purpose. Now when I turn the heating on the pipes heat up all the way to the back boiler and do not circulate around the radiators, so Im thinking the non-return valve would have stopped the flow to the back boiler when it was not required?

Dtp1979

A few pics of the pipework would help please.

JR1210

The first image the non return valve was to the left of the drain valve so when you tried to drain the system the water didnt come out, that was the only thing removed from the system so I am thinking it must be affecting the circulation

JR1210

https://drive.google.com/file/d/0B9tLbkz7TGsWaE43VVRieUpHZl8yLW5NbGEySng4UEdPNGJj/view
https://drive.google.com/file/d/0B9tLbkz7TGsWbzRYZFlHZjdqTTZzQm4yNFRXMjFtd1RIQXZB/view

K.Flyer

To be honest, you really need to get a plumber who knows and understands heating systems to take a look at it and work out where things have gone wrong.
It may be that it only needs the non return valve replaced, but there may be other errors as well, so the system needs to be looked over to ensure the rest of it is in good order.

NIALL D

He should not have takin out the non return valve , it was there for a reason !!
Depending on your set there should even be 2 !
One at the oil boiler and one at the back boiler .
Thats the whole idea of them , as in if you turn on oil boiler it should not heat the back boiler ! Which is probably whats happening. The back boiler is acting like a radiator an just taking all your heat and being wasted and the fact that back boiler connections and pipe work are always 1 inch the hot water will take that quicker easier route through the system and not travel as much through the half inch pipes and valves at your radiators ..

Normally i think the best setup is have the pump and non return valves on the return jus next to both the oil boiler and back boiler ..
So basically on return / bottom connection on either boiler have non return valve then pump then your boiler ..

Put the non return valve before the pump rather than after because sometimes if there the other way round they tend to make noise ..

I put pumps and NRV's on return always , better setup , often pumps on flow dont last as long because of heat and rubber seals often fail etc ..

Also always vent the pump by opening the big screw on the front ..

Radiator wise i normally balance them , as in on one side there will be a valve that cant be adjusted by the head called a lock shield valve . Close fully the open fully , count the turns and set at half way open , do this to each rad .. Then the valve on the other side you use to turn on or off , or depending on how much heat you want from the rad you can adjust it to suit ..

Probably best get a plumber to take a look over to be safe , make sure the top pipe / flow pipe on your back boiler rises alll the way to vent pipe in the attic and also make sure theres a pressure release valve on the flow also ..
If neither of these are done properly you could be looking at a ticking time bomb ..

This is just advise also dont quote me on this , as i said best to get a plumber to look over it !!

JR1210

Thanks Niall, makes a lot of sense