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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. B

    installation of Boiler - Unvented tank

    As part of a rebuild (added 1st floor to bungalow and extended back) we have removed every piece of plumbing and electrics, during COVID In preparation for the complicated stuff, during the build we have ... Gledhill unvented tank (preplumbed) placed in 1st floor airing cupboard New...
  2. M

    Buffer Tank/Thermal Store addition to S Plan Plus & Unvented Cylinder?

    Hi sorry bit of an odd query here. With the increases in energy costs now and in the future we are trying to find any way to reduce our exposure (retired couple on fixed incomes). We are fortunate enough to have bought solar panels at the beginning of the year but as we head towards winter the...
  3. M

    Renewing unvented quals

    Anyone know what is involved in renewing unvented qualifications. Is it a few written questions and a practical fault finding on unvented? I got my original through my level 3.
  4. M

    Combi vs unvented???

    Hi guys. I know there’s a lot of people who are happy to just chuck in a combi on every install, whether it’s suitable or not. What I’d like to know is, in what situation do you refuse a combi? Obviously things like a 4 bathroom house might not be suitable but what about cost savings with...
  5. H

    Unvented cylinder for ASHP

    Hi all. I have an Isoflo CL170 cylinder with good few years life left in it in my system which has performed trouble-free other than the odd new immersion element. I'm getting a new ASHP fitted and the installer is recommending scrapping the Isoflo and replacing it with a Secon Trade Heatpump...
  6. B

    Boulter Camray 2 to run unvented/ pressurised

    Hello, Re-jigging a serviceable Boulter Camray 2 boiler to run presurised instead of gravity. Manual says it can but we need to fit Manual reset Limit stat and Phail tube to put into boiler for sensor -both available. (Also Expansion vessel obviously!) This seems straightfrward - any comments...
  7. R

    Unvented cylinder viability??

    I'm looking at getting an unvented cylinder fitted but want to know if it's viable before even getting a quote. My cold incoming main is only 15mm but I do get a good pressure and flow which doesn't change alot when another tap or shower is used. Would an unvented be possible?
  8. 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.
  9. 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...
  10. 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...
  11. 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...
  12. 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...
  13. 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...
  14. 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
  15. 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...
  16. 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...
  17. 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...
  18. 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...
  19. 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...
  20. 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)...