Honeywell Straight Auto Bypass Valve 22mm Product Code: 34127

22mm. A simple means of ensuring adequate flow through boilers which require a bypass.


  • Reduces System Noise
  • High Flow Capability
  • Easy Installation
  • Ideal for Combi Boilers


Factory set to 0.2bar (adjustable up to 0.6bar). EN 1254-1.
Additional Information
Technical Specification
  • Brand : Honeywell
  • Product Height : 80 mm
  • Product Type : Straight Auto Bypass Valve
  • Model No : DU144A1001
  • Product Width : 40 mm
  • Product Depth : 80 mm
  • Pack Size : 1
  • Product Diameter : 22 mm
  • Manufacturer Guarantee : 1 Year Guarantee
  • Pieces in Pack/Case : 1
  • CE Standard (Tested to EN...) : EN 1254-1.
Product Contents
Delivery & Returns


Standard delivery: €15

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€56.95 Incl. 20% VAT

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Honeywell Straight Auto Bypass Valve 22mm is rated 3.3 out of 5 by 3.
Rated 1 out of 5 by from Unreliable product. I can't recommend these valves. I have now had to replace mine for the second time as the two I've had both failed within two years of fitting. They both got stuck partially open causing permanent bypass. Even when brand new they were imprecise in operation and difficult to adjust correctly. I used the Honeywells as my pipe layout could only accommodate a straight valve. I've now reworked the pipework so I can use the more common angled type and the valve I've now fitted works better than the Honeywells ever did.
Date published: 2013-04-18
Rated 4 out of 5 by from Reliable Another reliable and quiet product from Honeywell if a little expensive
Date published: 2012-10-08
Rated 5 out of 5 by from Every system should have one After having problems with badly adjusted bypass ccts - a revelation. Just fit this in place of the old Gate valve, adjust for min boiler requirement and its done - maximises efficiency and prevents problematic overheating - especially when using multiple TRV's. £30 is a bit steep - but will probably save that in gas bills very quickly. Long term reliability remains to be seen - but no problem so far.
Date published: 2009-02-06
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