Hey guys, are there any gas/oil/plumbing engineers among us as I would love some advice!

 

Main thing is converting from a solid fuel vented to a closed system combi, so if anyone else can shed light on this having carried out this convention please feel free to give opinions and so on!

 

Many thank guys,

 

Hollings

Assume the solid fuel boiler is a back boiler ( behind / build into fire place) if so depending on age its likely the hot water is just gravity and the heating pumped, now if as said, the hot water cylinder will be as close to above the fire as possible, usually in a bedroom airing cupboard.

 

As the major connection parts of the heating system are with in the airing cupboard area the easiest location for the combi is where the old cylinder is, now this is subject to flue and ventilation requirements and getting a gas supply to that area, so this will need to be surveyed.

 

The old system flow and return from the solid fuel boiler will rise up into to the airing cupboard and most likely on large 32 mm pipes that will need reducing down to meet up with a modern combi-boiler, as far as the hot water is concerned all you need to do is connect the hws output to the nearest hot tap supply that will of been previously connected to the cylinder, the cold water supply to the fill and expansion tank will either be sitting atop the cylinder or in the loft (depeding on the age of system), this cold water supply will need to be connected into the combi-boiler for flexi-link system fill and for the hws.

 

Other things to consider is size of boiler ( btu rate) do not be tempted to skimp on a smaller output, always better for performance and economy to have a boiler that can easily supply a system with heat and hot water with out running full tilt all of the time, modern boilers are designed to get up to to temp and then not actually switch off but modulate the gas rate to the burner ( a bit like turning the flame down on a gas ring) and also ramp the speed of the pump up and down to help regulate flow/ heat rate this only works well if the figures have been done well, so add up your room size btu requirement based on the house material type, brick wood glass areas etc and when you have your total add 30%, also if you want to run showers from the hws check the hot water flow rate per minute, often cheaper compact combi`s cannot deliver constant hot water in Winter time to a shower or even to fill a bath but are ok for wash basins etc.

 

Google for help with the system calculations or even ask your boiler supplier to work it out for you.

 

Jeff TT

Sign up on the 350z-uk forum and PM a user called NeilP. Tell him I sent you for advice.

cheers jeff! i gathered most of that in bits and pieces but saying it like makes it so simple, will be removing all the radiators and have already got BTU reqs for all rooms and chosen rads.

 

The house im purchasing currently only has 6 rads and being a 3 bed it pointed at a 24Kw, i ignored that and will fit min 28kw, and brand will either be valiant or Worcester Bosch.

 

ill look into that lexx cheers!