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norfolkboy
10-07-2009, 11:20 PM
hi all in uk,
i have been asked to price up some work for leak testing 3 pipe vrvs to comply with f gas regulations. My thoughts are that it accetable to check delta t on say 25% of air handlers with all at 100% duty. assuming the ambient is reasonably consitenant and all units are working, clean, etc these temps taken, recorded and compared with previous years results will give a good indication of gas charge. This would be recorded on a log sheet, the sheet that defra have supplied a sample of is much more suited to rerigeration than a/c. obviously leak testing needs to take place when a leak is suspected. What are others doing or proposing to do?
many thanks.
paul.

taz24
10-07-2009, 11:28 PM
hi all in uk,
i have been asked to price up some work for leak testing 3 pipe vrvs to comply with f gas regulations. My thoughts are that it accetable to check delta t on say 25% of air handlers with all at 100% duty. assuming the ambient is reasonably consitenant and all units are working, clean, etc these temps taken, recorded and compared with previous years results will give a good indication of gas charge. This would be recorded on a log sheet, the sheet that defra have supplied a sample of is much more suited to rerigeration than a/c. obviously leak testing needs to take place when a leak is suspected. What are others doing or proposing to do?
many thanks.
paul.


Why only 25% of the systems.
All the systems need maintaing so why not do the tests then. If a propper PPM is done that covers all the requirements as far as F gas goes.

It is the Planned Preventative Mantenance, done correctly that minimises the loss of gas and inefficiencies.

taz.

.

norfolkboy
10-07-2009, 11:40 PM
hi taz,
i was thinking that all units would be checked for temps at air handlers. but as far as logs are concerned 25% of a systems would indicate a charge issue without over complicating log sheets. i feel that easy access to the history would show up trends and the sheet in circulation does not lend itself to this and was woundering what to do. the first job i have got to price is 12 x 3 pipe systems with 12 air handlers on each system. the customer has several other sites with multiple vrvs on.
does any one use such a log sheet?
thanks paul.

taz24
10-07-2009, 11:49 PM
hi taz,
i was thinking that all units would be checked for temps at air handlers. but as far as logs are concerned 25% of a systems would indicate a charge issue without over complicating log sheets. i feel that easy access to the history would show up trends and the sheet in circulation does not lend itself to this and was woundering what to do. the first job i have got to price is 12 x 3 pipe systems with 12 air handlers on each system. the customer has several other sites with multiple vrvs on.
does any one use such a log sheet?
thanks paul.


But the reason the log sheet is used is to flag up history.
How will you build up a history if you only check a 1/4 of the kit.

All the equipment needs checking twice a year and a log needs to be completed of all work carried out.
The log sheet could be a blank piece of paper, it is not important what format it is in.
The important part is that a comprehensive maitenance is carried out. If the site has lots of kit the owner will have to pay for the labour costs.

But what I can't understand is why don't you do PPM's on the kit?
You can't just randomly select 1/4 of the kit and just test that. 100% needs checking always.

taz

.

El Padre
11-07-2009, 02:17 PM
A visual inspection, electronic leak detection should both be included along with the run log data, you can get the thermistor values from the controllers it does'nt take very long at all, and you should surely be logging/checking all of the system.
The bigger systems might have a slight oil leak months or even longer before performance is comprimised.

Cheers