Jimmyjazz

I may have used the wrong terminology trying to simplify the situation. if you put a hose pipe on the return bar of a manifold you should not get any flow back through to the flow manifold. Give it a try. They don't pass. They don't however have what you would call a traditional check valve

Often pumps are not required on underfloor manifolds. When mixing valves are added you often need to add a pump to overcome the resistance but as you say if you are getting flow in the other circuits there is most likely an issue on this circuit. When you tried to flush the loop before, did you put the hose on the flow or return? there are non return valves on the manifold so if you are attaching the hose on the return manifold bar you won' push it through. You will blow the hose off as you have done. I would say it is highly unlikely to be a pump issue. Can you not get someone who knows what they are doing to take a look?

Mixergy cylinders are quite good. Give them a call and speak to them and they will explain them in detail. Having the ability to heat the cylinder at cheap electric times and also to be able to heat what you need is a great feature. We have come across quite a few people that have them now and everyone we have spoken to seems happy with them. Better than a conventional direct unvented cylinder and cheaper than the Thermino although I don't know much about the Sunamp heat batteries so I can't express much of an opinion on them.

RED = Hot (Or danger) or so I was led to believe!

If you are losing pressure from the system I would look for the cause of this. Adding leak sealer is just putting a band aid over the wound. Leak sealer has always been considered a last resort. When topping up the system pressure 2.1 bar is generally too high. Anything from 0.7 to 1.2 bar is normal system pressure when cold. Has your heating man checked that non of the air vents are leaking, expansion vessel pressure is good (is the expansion vessel sized correctly for the system volume), prv is not letting by etc. Are there any weeps inside the boiler or on any of the pipework and joints. Check all the above before adding leak sealer.

There should be a non return valve (check valve) on a secondary loop. Even if someone opens a hot tap during the period that the mains if off the secondary loop will drain of water and the pump will run dry. You could put a pressure sensor into the pipework like combi boilers have that would break the circuit if the pressure falls below 0.4 bar. Or alternatively if you know the water is going to be off, turn the power off to the secondary loop pump.

Henry hoover with Hepaflo bags. The bags stop any dust or soot from being blown back out of the hoover. The bags are £10 for 10 or thereabouts and last ages.

What happened to your heat pump? It looks like it's been in a fight! Firstly what price are you paying for energy? If the system was put in by an MCS registered company they will have given you a handover document with all heat loss information and anticipated running costs. What temperature was the system designed to? Was the system ever commissioned properly and flow rates and flow temperatures set? I would get an installer involved who knows about heat pump systems to have a look over the system and set it up properly in the first instance as it sounds like it was finished in haste and not properly done.

I have seen this site and drive past it regularly. A little too expensive and the application is not what I am looking for. Thanks for the suggestions though. The search will continue!!

Thanks for the Welcome. I'm open to a renovation as long as it's not listed!!

Having a vented cylinder with a large area coil (high gain) should be no problem. There are manufacturers that do this. Try McDonald cylinders. They would be able to help.

Hi hopefully, I can add a bit to the pot and hopefully learn a bit. I am looking to buy some land and build my own house if the land ever becomes available! Experience wise I was in the building industry and now the plumbing and heating industry so quite diverse. I am based near Bude, Cornwall.