24 April 2016:
I’ve given my blog a name: it acts an old curmudgeon’s soapbox, where I can not only share experiences, but vent frustrations so I don’t become a threat to anyone. (And also, I hope, give some compliments and praise.)
Boilers –
Boilers in lofts: a loft can be a good place for a boiler, and although it takes longer to service a boiler in a loft, it beats poor access and ventilation in an undersized kitchen cupboard. BUT, being at the highest point in the system, the boiler will be the first ting to suffer if system water is lost. In addition, the boiler’s indicators and pressure gauge are out of view and if the boiler needs to be reset, you’ll need to get up there to do it. Consider having a pressure gauge and filling loop fitted at lower level. Manufacturers –
More rain: a Potterton Suprima stopped working after a very rainy day. Rain had entered the air intake (under a failed gutter). All that needed to be done was empty the water from the tube to the fan air pressure switch and function was restored. In this boiler, parts that might have been damaged by water, are off to the side out of harm’s way.
Peculiar fan: my diagnostic skills weren’t up to a Potterton Suprima HE boiler –
Boiler first service in 21 years: serviced an Ideal balanced-
An odd case of a blocked plate heat exchanger: a Keston boiler as it happens, which had shown the signs of poor circulation –
Flues in voids: still finding the occasional flue in a void with no inspection hatches, in rented properties with clean gas safety certificates –
Rainwater in a boiler –
Rainwater in a boiler: during the last week in July 2013, after a rainstorm, attended a Worcester Greenstar 28i junior boiler dripping water. On removing the case, there was a considerable amount of water on the floor of the burner compartment. The tenant thought it was due to the rain, I didn’t, Worcester tech support (excellent people) did, and directed me to the gas valve. On removal, this was found to contain loads of water –
Gas pipes to hobs: Gas engineers occasionally find gas hobs supplied with gas via flexible cooker hoses . Gas hobs should be supplied via rigid pipework that contains an isolation valve, or if there’s a flexible pipe, it can only be permitted if it hangs in a U shape and is not under stress.
Balanced flue boiler: I recently had the pleasure of servicing an old balanced-
Soaking wet loft caused by boiler plume: my friend who installed his new condensing boiler in the “summer” of 2012 some time later had a soaking wet loft due to the plume rising several metres vertically in cold, still air, through the gaps (meant to be there) in his soffit boards, and condensing the remaining water vapour as liquid in the loft. Anyone else had this?. He solved it by extending the flue exhaust so it discharged well away from the house.
Damaged screw heads prevent proper boiler service: my efforts to do a proper service on a nine or so years old Ideal boiler were frustrated by damaged screw heads, left in that condition by a previous engineer. I didn’t try an impact screwdriver or drill out the screws for fear of causing real damage. The boiler was burning very badly, bad enough to be in the At Risk category. Fortunately, I was able to get at and clean the burner which greatly improved its performance, but a few carelessly damaged screws will probably result in the replacement of the boiler before its time.
Tech support: I recently repaired a limited edition Jaguar 23 boiler, which I gather was originally produced by Hepworth for Plumbcenter. Most Installation & Service manuals give detailed information on how to replace parts, but this one was particularly lacking on that score. No matter –
Corrosion products found in a boiler only 2 years old: probably responsible for failure of a pressure sensor, despite the presence of a magnetic filter in the boiler return. Cleaned the filter of fine black magnetite “silt” or “goo”. Tallies exactly with observations of a friend –
Worcester Greenstar 24i System – boiler service from hell. All looked well – the fan (negative) pressure comfortably exceeded the minimum and so indicated the boiler didn’t need a clean, despite not being serviced in the five years since installation. However, flue gas CO2 was considerably lower than the manufacturer’s figure (which has a tight tolerance). Adjusting gas valve to raise it had CO shooting up well over limit. Advised to look at fan baffle, which was fine, so having taken the lid of the burner/heat exchanger, proceeded to clean it –
Idea for electronic manuals –
Worcester Greenstar 24Ri –
Gas inlets on boilers (undersized): powerful combi boilers burn gas at a high rate and installers struggle to achieve adequate pressure at the appliance, aiming for less than 1 mbar drop in the pipework, and often resorting to 28mm copper pipe. It seems very odd that some manufacturers of hefty boilers (30kW and above), have a gas inlet of 15mm. According to my spreadsheet, you only need 0.5 metre of 15mm pipe with one elbow, to lose 0.5 mbar to a 35kW boiler. So, for the rest of the pipe run, you’ve only 0.5mbar to play with. The same in 22mm would lose less than 0.1 mbar.
Worcester combi boiler 532i (CDi badged by British Gas): bad leak on domestic hot water (DHW) side just before the plate-
Ariston Micro Genus HE 24: air flow problem (error 34). Changed the air pressure switch to find only minor improvement. Similar result after cleaning the fan. Took tech support’s advice and removed the flue flow restrictor from the flue adaptor on top of the boiler. Had to remove the flue elbow, with the help of the owner chiselling away mortar from around the flue. Reaching in with a finger and pulling out the restrictor from above (looks like a flat metal washer ~40mm diameter) was the work of a moment. Sorted. Not common to have to alter the “build standard” of a product like this – presumably some of these boilers on longer flues are now struggling. A new fan might have helped further, but the owner was spared the expense.
Vaillant EcoTEC plus 428 condensate trap difficult to remove: (heat-