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A gas heater is a space heater used to heat a room or outdoor area by burning natural gas, liquefied petroleum gas, propane or butane.
Indoor household gas heaters can be broadly categorized in one of two ways: flued or non-flued, or vented and unvented.

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  1. W

    Pressure reliefe pouring out of unvented immersion heater.

    Hi all. So I have an OSO Super SXD 180 immersion heater and it is pouring a huge amount of water out of the cold water pressure relief valve regardless of whether the tank is heating or not. We're talking litres a minute currently. I have replaced the valve which changed nothing. I have...
  2. P

    Unvented Cylinder Recommendations

    Hi all, looking for some recommendations for a slimline indirect unvented cylinder to go with a new system boiler that we're having installed soon. Only need around 120/125 ltr for our usage and could possibly make do with 100. Been looking at a few different brands including the Megaflo which...
  3. S

    Unvented extractor fan for gas cooker

    Hi guys I'm moving to a flat but where the cooker is situated. I can't get a vented extractor fan as it's the same wall as the next door flat. Are the none vented ones any good ? Which one should I be looking out for ? Or avoid ? Any tips will be helpful
  4. R

    Unvented cylinder no cold water to multiple outlets

    Hi, I’m having issues with cold water to multiple outlets. Taps, showers, toilets cold water is fine at the kitchen sink. The hot water system is a Glenhill unvented cylinder. Hot water is fine at all outlets. I assumed the cold outlets not working were from the balanced cold from the...
  5. N

    Draining an unvented cylinder

    Hi, According to the regs, can I (homeowner/DIY-er) drain and refill an unvented cylinder myself, or does that require a plumber with G3 cert? Cheers
  6. Z

    Thoughts on Prostel unvented cylinder horizontal

    Just looking at getting an unvented cylinder. Screwfix do an RM cylinder called Prostel. Anybody had experience with these. £830 for 250l horizontal.
  7. ridgerunner

    Will switch to unvented HW cylinder reduce shower performance

    Hi, am getting our bathroom updated and local company suggested ditching our traditional attic CW tank/vented cylinder and pump for the shower and install an unvented pressurised HW cylinder instead. We have been told that this will not lead to a drop in effective pressure from the shower. Is...
  8. dave100

    New unvented cylinder / Replace old vented cylinder and add a ST pump?

    Hello, I am renovating a small bathroom in an apartment on the 5th floor. Heating is electric, no gas or oil. I have four (related) questions about this below. I had intended to reuse the cold water tank and the cylinder sitting underneath it but my plumber suggested I replace the cylinder as...
  9. A

    Can unvented cylinder discharge be connected to this overflow?

    Hi, I'm looking to install an unvented cylinder in my property. I initially hired a plumber who expressed interest in the job, but later cancelled, citing "building regulations" as the reason, specifically regarding the discharge pipe and its location. Subsequently, I reached out to my second...
  10. M

    Unvented cylinder install query??

    Hi guys. Is there any reason you can’t can’t downsize the hot water draw off from 22mm to 15mm straight away? Other than the flow rate being affected would there be any other concerns? Cheers
  11. M

    Heat pump unvented install balanced cold

    If changing a combi boiler system to a heat pump. What do they usually do with the balanced cold connection on the hot water cylinder? Cap it. And put a pressure reducer on the mains so they have equal hot and cold pressures? I can't see them repiping a balanced cold from the cylinder to each...
  12. T

    Unvented Expansion Vessel Replacement - what else needs changing

    Potable water unvented expansion vessel needs replacing - water is coming down the tundish. What else needs to be replaced. Does the enginneer need a G3 unvented certificate to do this work and what are the consequences if he does not have one
  13. S

    Unvented Tank Advice Please

    Hi. I have looked at similar posts but not seen exactly what I'm after ... unvented Gledhill 200l fitted a few months ago. A few weeks after and since most times when we turn on hot water tap in the morning there is a long groaning sound (I have a recording if it helps). Have contacted...
  14. N

    Unvented cylinder size

    200/210 or 250l indirect unvented cylinder... Pros and cons of both please guys, whats the thinking?? Better to go bigger, or are there other considerations to be thought of....?
  15. D

    Efficient way to heat radiators and unvented cylinder

    I have a gas boiler heating radiators and also heating an unvented cylinder. I have a Honeywell programmer which has the water heating up 1.5 hours early morning 30 mins midday and 2 hours evening The heating is on a couple of times a day. With the energy prices I am wanted to ask if hearing...
  16. A

    Plumber Qualifications Query

    Hi. I have an elderly neighbour getting quotes who has asked for my help and opinion, I don't really have a good one as it is not my area of expertise but I am trying to help. The quotes are all similar prices but She seemed to like one person and quote more than the others and I noticed that...
  17. J

    Unvented cylinder recommendations?

    Hi all, I'm due to install my first unvented cylinder. (I've had my unvented ticket for several years, but not actually done a brand new unvented install yet). It's a house renovation, with a new hw and heating system. The house currently has an old gravity floor boiler, that will be coming...
  18. D

    Unvented water heater advise

    Been to a site today and every sink has a 15l water heater underneath on each of the prv's discharge after the tundish their is only about 200mm of 22mm copper before it enters the sink waste below each sink been like this 10+ years their is no other pipework local to each and most of the...
  19. J

    unvented cylinder v combi store

    Hi all, My customer is renovating a house. Complete renovation of the plumbing. It's a three-bed house for a young family of 3. It will have one main bathroom (bath and maybe an over-bath shower), plus two shower ensuites. I have yet to check the incoming water pressures/flow rates to the...
  20. Fogster74

    Working on heating side of system with an unvented cylinder, no G3?

    Hi all, I'm a competent DIYer with an engineering background and am active in Heritage Buildings. I never touch anything I'm not allowed to albeit I've worked on the wet side of my own heating on the central heating circuit before when I had a combi - balancing rads, add a Fernox TF1, washing...
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