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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. C

    Unvented Center cylinder no hot water

    Hi all, I’ve got an issue with no hot water from Center 300L unvented Cylinder on S Plan plus system. All Electrical controls working fine. Only way to get hot water to the taps is by using immersion heater. Any ideas what could be up? Thanks in advance.
  2. J

    Suitability of Unvented Cylinder

    Hi I've read through dozens of threads on here about unvented systems but was wondering if someone might provide some advice on an upgrade we are planning as part of a bathroom refurb Current Setup: Gravity fed system with cold water tank in the loft and hot water tank in the hot press (1st...
  3. G M

    URGENT Unvented Cylinder Gushing Water from Relief Valve?

    Hi folks, I hope someone can help me. This morning we noticed water leaking under the hot water cylinder in hotpress room. On closer inspection, the water was just gushing on to the floor and it was only by chance we noticed it. We turned off the heating system and spent the morning emptying...
  4. O

    Unvented cylinder - usage question

    We have an unvented cylinder with a Horstmann Electronic 7 timer. The cylinder only serves a wet room which is very rarely used. The rest of the house is served by a Vaillant combi boiler. The timer on the cylinder is set to heat up water 3 times per 24 hours, which I think it is the default...
  5. R

    Advantage of unvented cylinder outweigh the disadvantages?

    I have come to my decision I might as well do my G3, even if only for maintenance jobs. Question I have is WHY we are fitting so many of these unvented cylinders i.e. 27 gallons /117l size or above (I'm not disputing the need for 10l unvented 'cylinders'). They 'need' annual servicing by a G3...
  6. R

    Do I need G3 to repair a 10l unvented cylinder?

    Hi. Potential customer has a leaking 10l Ariston Europrisma cylinder. Probably just a flange gasket or the magnesium anode needs replacing. While I feel this is easily the sort of task I can tackle as I am very good at mending things, I get the impression I'd need my G3 to install such a...
  7. S

    Insulate a Unvented Cylinder

    Hi I have a warmflow unvented water cylinder (indirect 250) in a hotpress. It was installed two years ago, but never had any lagging put around it. Wanted to ask if that would have been for a reason why it wouldn't have, and also would insulation be a good idea to warp around the tank? Thanks
  8. I

    Draining ACV unvented Cylinder

    Hi Guys, has anyone come across the ACV cylinders, my client has SLE-160 in the loft and there is no drain off boss.. The cold inlet is on the top next to the hot outlet. I need to replace the immersion element located at the bottom of the tank. MI is not helpful. Possibly looking at...
  9. B

    Advice needed with my Hive Multi-zone and unvented tank

    Hi, I'd appreciate a bit of advice about my hot water and heating system.. So, we moved into a new build about 5 months ago and we have a TheraQ ProLite SS 250 unvented tank, we also have a gas boiler and Hive multizone. My understanding is that the boiler sends hot water to the tank to heat up...
  10. S

    Can remove limescale from unvented direct cylinder (center store)

    I have an unvented direct cylinder from centerstore to use it only for hot water CenterStore direct unvented cylinder 120ltr | Wolseley - https://www.wolseley.co.uk/product/centerstore-direct-unvented-cylinder-120-ltr/ but with two immersion heaters. I had it the cylinder working fine for 4-5...
  11. R

    Normal unvented indirect tank or high gain unvented indirect tank

    Hi, Trying to decide which cylinder to go for? I am renovating my house which will end up having four bathrooms and a wc. I am planning to go for a 300l unvented indirect cylinder as currently I have a vented cylinder with a cold water tank in the loft and face issues with hot water pressure...
  12. J

    advice on timer control for Unvented Cylinder

    Would need some advice if I could replace Newlec Economy to OP Ecosave Timer control for “Unvented Cylinder Megaflo Water heater” As the current Newlec Economy timer control limits to heat up full tank of water during midnight only( one time a day. ) OP Ecosave Timer control allows to set...
  13. D

    Electric boiler and an unvented indirect hot water cylinder

    Hi, I have recently purchased a cottage with an LPG combi boiler (no mains gas in the area). I intend to replace this with an electric boiler and an unvented indirect hot water cylinder. The boiler will run four radiators and the hot water cylinder. The cottage has one bedroom. What size (kw)...
  14. J

    Plumber or electrician to replace new timer switch Unvented cylinder

    Replace the current E7 Newlec Economy control to a mechanical 24 hour timer switch for unvented cylinder water heater, may I know if I ask plumber or electrician to do this job. Because Newlec Economy controller can heat up water once a day in midnight .I would require constant hot water in...
  15. E

    Leaking Unvented Hot Water Cylinder

    Hi, I've got an unvented hot water cylinder with a leaking pipe. The job is in a residential property in pontefract.
  16. D

    Unvented cylinder location

    Hi all, I have a fairly large property (6 bed 4 storey victorian) and when we moved in the pre-historic boiler broke down and it resided in its own boiler room attached to the kitchen. It broke down in November 19 and had a nightmare getting anyone to fix it but they said it was unrepairable as...
  17. S

    URGENT New Gledhill Stainless Lite Indirect Unvented alarming popping noises.

    Happy Christmas everyone, We’ve just had a new Gledhill Stainless Lite indirect unvented cylinder installed by Dyno. It is making an alarmingly loud popping noises when the hot water is being used, not always but very very often. Mentally to me, it seems like the inner casing of the cylinder...
  18. J

    Unvented cylinder installed but no G3 qualification

    I had an unvented cylinder (and gas boiler) installed by a Gas Safe Register engineer. He later informed Gas Safe Register which issued me a gas certificate. But Gas Safe Register told me I should have a Building Regulation Certificate for unvented cylinder installation. But the gas engineer...
  19. J

    Advice on Install a new Electric Shower (currently unvented cylinder)

    Advice on Install a new Electric Shower for shower cubicle and keep using the unvented cylinder water heater for bathtub I have an Unvented Cylinder Water heater 125 litre (MegaFlo) in an apartment of ( 15 years old) Currently it is not really capable of delivering enough hot water for more...
  20. J

    Tundish in unvented cylinder system throwing lots of hot water away

    We’ve had some issues with our boiler system making loud noises recently which sound like a bath being filled when you’re sat downstairs. Upon inspection of the cylinder upstairs (boiler is downstairs), we can see lots of hot water coming out of the tank through the tundish and we have no idea...