topic Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings in Revit MEP Forum

Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

kyle.klouzal — Mon, 19 Aug 2019 15:28:42 GMT

I've been trying to figure out how to properly setup MEP for copper HVAC refrigeration piping, specifically line-set for a Mitsubishi multi-split system.

A new "Pipe->Pipe Types->Mitsubishi Line-Set" family has been created and "Routing Preferences" have been set as shown below. Another point of interest is in creating a "R-410A" fluid type, can anyone direct me to the information required to accurately fill this out?

After setting everything up as shown above I am still unable to link pipe between my mechanical devices.

Revit could not find a matching Pipe Segment in "Pipe Types: Mitsubishi Line-Set". Please check the routing preferences of "Pipe Types: Mitsubishi Line-Set".

That warning appears when trying to connect pipe of size 1-1/8 and 5/8, however 1/2, 1/4, and 3/4 works fine.

I'm not sure why 1-1/8 and 5/8 throws the warning when it looks as though they've been defined in "Segments and Sizes".

Can anyone help me with these problems? Better yet would be access to a BIM file containing project standards already setup for this specific task that I can transfer over into my project.

I've seen posts requesting these very same things with no clear cut answers in the past, it seems like it should be a part of the core Revit software when so many people require use?

Thank you for your time!

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

RobDraw — Mon, 19 Aug 2019 16:23:23 GMT

Have you checked your routing preferences to verify that they are complete and correct?

Why are you going through this exercise?

We utilize manufacturer's reps to do these system calculations and typically only show 1 line routing to indicate all three pipes as these pipes are usually not included in interference checks. These systems have some specific requirements/limitations that Revit may not be able to account for.

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

kyle.klouzal — Tue, 20 Aug 2019 16:29:39 GMT

I'm learning how to use the many different aspects of Revit. Up until now I have been able to find solutions for any issues I came across. HVAC design is one particular subset of designing self contained systems within Revit so I want to make sure I understand how to properly set them up. Most modern equipment use R-410A which is why I would like to understand how to properly setup a "R-410A fluid type". Most importantly though is this problem when trying to connect pipes between the various pieces of equipment as described in the first post.

I believe I have the "Segments and Sizes" setup accordingly however something must be wrong since the warning is being displayed: "Revit could not find a matching Pipe Segment in "Pipe Types: Mitsubishi Line-Set". Please check the routing preferences of "Pipe Types: Mitsubishi Line-Set"

Thank you again for your time.

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

RobDraw — Tue, 20 Aug 2019 17:53:45 GMT

One thing that sticks out is that your routing preferences do not have any fittings assigned. I know the message indicates segments, not fittings, but it might be part of the problem.

If the problem persists after setting the routing preferences properly, posting a model that exhibits the behavior and a screencast of what you are doing, will help with modeling the pipes.

As to the fluid calcs, I'm not sure Revit is ready for refrigerant. You may have to rely on other software for that.

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

collinsrevit — Tue, 21 Sep 2021 05:04:31 GMT

Finally I have managed to solved this problem. I am just 3 months into using revit and absoluterly stoked to crack the logic of the connectors. What I have found is if there is anything that matters it is the logic of connectors and pipes. This problem arises when the connector size of the revit family is different from the pipe sizes avaialbe in routing preferences. For examples : If you have 20mm, 21mm,22mm and 23mm pipes in routing preferences but your pipe connector is 7mm , the error would come up because your routing doesnt have 7mm pipe.

One easy way to fix this is making your own pipe sizes that you will be using . As I am based in NZ, I used the table below to create my own pipe routing .

https://www.kembla.co.nz/Portals/0/Products/Brochures/ASNZS1571%20Refrigeration%20&%20Med%20Gas%20Brochure.pdf

Once the pipe sizes have been created , modify the mitsubishi VRF fancoil connectors to sizes availble from your created size list. Remember , a pipe will have nominal dia, internal dia and outsize dia. While resizing family connectors, make sure you use the nominal dia of the pipes availble or else error will persist.

Example: If DN - 7mm OD -6.35mm and ID - 5.8mm then the pipe connector on the fan coil should be 7mm in dia or 3.5mm radius( whichever has been selected).

After that load the family in project and use your 7mm pipe to connect with it. I believe it wil work .

Let me know how it goes.

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

RobDraw — Tue, 21 Sep 2021 09:45:11 GMT

Prepare for balloon bursting, sorry.

What's going to happen when they go to build the system and they find out that the unit does not come with the size connectors that you made or maybe it won't work properly with the size pipe that you chose?

What you really need to do is make the correct size pipe or put an adapter (reducer) into the routing preferences that will allow a connection to be made that will adjust to size pipe that you have available. I'm having trouble believing that the correct size of refrigerant piping is not available, though.

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

HVAC-Novice — Tue, 21 Sep 2021 13:54:25 GMT

I think you are over-doing it. refrigerant pipes are sized by the manufacturer. They are picky and proprietary about slopes, oil return, flow velocities, lengths, elevations etc. In addition, you have a gas, and a liquid phase. Revit really isn't build for that. Refrigerant also often uses soft copper with large radius bends. They also use the longest possible coil to avoid fittings. Fittings are possible leak points.

So what I would do is talk to a rep and read the manual to find out maximum lengths, approximate line sizes, and other limitations (height etc.). then find a route that would work and double-check with the rep if that is OK. Then in Revit you just show the route, and approximate sizes so that there actually is a viable route. Refrigerant lines usually are thin, but you want to avoid creating traps when you go around beams etc. The specific design of oil traps etc, is up to the contractors (done by manufacturer they buy from). I wouldn't model all that. the contractor would submit that design during submittal review. If your specs allow multiple manufacturers, chances are, this will differ based on actual model chosen.

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

iainsavage — Wed, 22 Sep 2021 06:20:19 GMT

Most of what you say is correct and we've probably all, at some point, had to create custom pipe segments, fittings and routing solutions.

I don't however agree with changing the size of the connectors on the manufacturer's family - those are the sizes which will arrive on site and someone is going to have to make a connection to them so what you need is a suitable adapter (union or transition) which matches the pipe and equipment sizes (exception being when the manufacturer uses the outside thread size instead of the nominal size).

You could use a generic family which adjusts itself based on the pipe radius/diameter, or create the correct fittings to suit the various dimensions that you'll encounter, or just accept the custom fitting which Revit creates for you, or nest a suitable coupling into the manufacturer's equipment family.

One thing to note is that the pipe connections on a lot of Mitsi equipment comes out at a weird angle so you can't just connect pipe vetically or horizontally off of the equipment, you have to slope up at some strange angle until you've created enough space to introduce a bend- I usually do this in a section view.

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

HVAC-Novice — Wed, 22 Sep 2021 12:36:39 GMT

Typically my families have the correct and actual size of connection and then transition to the pipe size the system has. Sometimes it is the same size, sometimes not. but that doesn't really matter since the contractor will just have to figure it out. If that connection is threaded, welded, soldered, or whatever... that doesn't have to be modelled in Revit. It really only matters that you specify the correct model and that comes from the factory whatever it comes with. For refrigerant equipment I wouldn't even bother to label the line size since that really depends on the manufacturer (unlike hydraulic equipment, where I make the pipe size decision).

Manufacturers also could change the type or size of connectors the equipment comes. I wouldn't want to box myself into a specific size when I already specified the model number.

Model as complex as necessary, and keep it as simple as possible. KISS.

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

iainsavage — Wed, 22 Sep 2021 13:34:15 GMT

I was referring to when manufacturers have connector sizes of say 19.1mm because that’s the machined size of the threads, but the nominal size is 20mm or 3/4” - nobody that I know would try to buy a 22mm by 19.1mm adapter, they would buy a 22mm copper to 20mm male iron as an example.

I also wasn’t advocating modelling refrigerant systems in minute detail but I use the schedules in the model to generate bills of quantities for tender purposes so I put enough detail in to make sure the quantities are reasonably close to being accurate.

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

HVAC-Novice — Wed, 22 Sep 2021 18:56:38 GMT

Just use one of the nominal sizes that are close to 19.1 mm and Revit will transition to the field-piping.

You do know that nominal hydronic pipe sizes are different from refrigerant line sizes. And it doesn't matter for Revit, or the contract documents.

Don't need to model every fastener to exact size either.....

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

iainsavage — Wed, 22 Sep 2021 20:52:42 GMT

@HVAC-Novice wrote:
Just use one of the nominal sizes that are close to 19.1 mm and Revit will transition to the field-piping. Yes, that would be the custom fitting which Revit creates and which I said was a valid option.

You do know that nominal hydronic pipe sizes are different from refrigerant line sizes. And it doesn't matter for Revit, or the contract documents. YES, I’ve been doing this for a long time now, starting with ink on tracing paper, through Autocad and now in Revit. Next move will be retirement (soon I hope). I also understand the differences between copper, steel, ductile iron, plastic pressure pipe, plastic waste pipe sizes etc. The sizes that I quoted were just examples.

Don't need to model every fastener to exact size either..... Didn’t say that I would but what’s the point in using BIM if your not making use of the “I”? You seem to be implying that I’m an idiot for modelling pipes? Using Revit schedules to generate bills of quantities saves me countless of hours of poring over prints, counting and marking off all of the fittings, populating take-off sheets, totalising and then typing into a spreadsheet - and I do need to account for all those fittings in tender documents.

Straying from the point of the post though? What I was saying is that its not difficult to include a coupling to transition to the equipment.

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

collinsrevit — Wed, 22 Sep 2021 21:16:56 GMT

If you look at the generic segment and sizes for copper pipes that comes loaded in Revit, they are different from the standard sizes we use in NZ and by Mitsubishi. So I had to create my own routing and fittings anyway to match with the connector size of the fancoils , I didn't have to change the size of the connectors on the fan coil or the distribution box. So that was an exaggeration, my bad!

So basically changing the pipe routing fixes this problem. For bigger units we just combine two connectors of the distribution box into one. I double checked the design for a system with the same that was provided by Mitsubishi. They both conform to each other.

P.S. The reason I had the change the connector sizes on the fan coils was coz I edited the original sizes to fit match the generic routing preference size of copper pipes in Revit which are different from the sizes used by Mitsubishi and NZ.

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

HVAC-Novice — Wed, 22 Sep 2021 21:53:52 GMT

I'm not saying modeling and scheduling pipes is bad. But detailing every fitting is overly complex IMHO. YMMV.

I also simplify straight pipes and in my model they just look like one long pipe. In practice, it may be multiple 8'sections with fittings. I don't model and schedule all the fittings. Obviously someone may benefit from modeling all fittings.

I also change the level of detail depending on if this is done by a contractor (and they have to figure out number of parts), or if that is a project I have to order all material for.

Typically the installer will just order special fittings based on what they see or worked out from the submittals. This isn't something that needs to be in the model. Chances are, due to some manufacturing change, or using of a different manufacturer or model, they need to use something else anyway. And the installer will change routing somewhat anyway.

As for the nominal sizes: the actual pipe size (ID) is important for hydronic calculations. So that should match what is nominal in your country. Otherwise the velocities are wrong, and with that presssure drop. For refrigerant, that calculation isn't done in Revit. So you only really need a separate pipe type for scheduling purposes.

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

RobDraw — Wed, 22 Sep 2021 22:39:27 GMT

Way to bring it back around to the question about the fluid asked in the OP!

CHEERS!!!

What you model and to what detail is subjective. The ways and means vary as much as the opinions in this thread.

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

collinsrevit — Wed, 22 Sep 2021 23:15:00 GMT


LTemperature℃	VDynamicViscosity Pa·s	LDensity kg/m3
-128	0.00016	1574.09925
-127	0.00019	1571.27663
-126	0.00021	1568.45392
-125	0.00024	1565.63096
-124	0.00028	1562.80762
-123	0.00031	1559.98376
-122	0.00036	1557.15924
-121	0.00040	1554.33395
-120	0.00045	1551.50775
-119	0.00051	1548.68052
-118	0.00058	1545.85214
-117	0.00065	1543.02249
-116	0.00073	1540.19146
-115	0.00082	1537.35893
-114	0.00091	1534.52480
-113	0.00102	1531.68894
-112	0.00113	1528.85127
-111	0.00126	1526.01166
-110	0.00140	1523.17002
-109	0.00156	1520.32624
-108	0.00172	1517.48022
-107	0.00191	1514.63187
-106	0.00210	1511.78107
-105	0.00232	1508.92774
-104	0.00256	1506.07177
-103	0.00281	1503.21306
-102	0.00309	1500.35153
-101	0.00339	1497.48707
-100	0.00372	1494.61960
-99	0.00407	1491.74900
-98	0.00445	1488.87519
-97	0.00485	1485.99808
-96	0.00529	1483.11757
-95	0.00577	1480.23355
-94	0.00627	1477.34595
-93	0.00682	1474.45466
-92	0.00740	1471.55959
-91	0.00803	1468.66064
-90	0.00870	1465.75772
-89	0.00942	1462.85072
-88	0.01018	1459.93955
-87	0.01100	1457.02412
-86	0.01187	1454.10432
-85	0.01279	1451.18006
-84	0.01378	1448.25122
-83	0.01483	1445.31773
-82	0.01594	1442.37945
-81	0.01712	1439.43631
-80	0.01838	1436.48819
-79	0.01971	1433.53498
-78	0.02111	1430.57657
-77	0.02260	1427.61287
-76	0.02418	1424.64375
-75	0.02584	1421.66910
-74	0.02759	1418.68882
-73	0.02945	1415.70278
-72	0.03140	1412.71087
-71	0.03346	1409.71297
-70	0.03562	1406.70896
-69	0.03790	1403.69871
-68	0.04030	1400.68210
-67	0.04282	1397.65900
-66	0.04546	1394.62928
-65	0.04824	1391.59281
-64	0.05115	1388.54946
-63	0.05420	1385.49907
-62	0.05740	1382.44153
-61	0.06074	1379.37667
-60	0.06424	1376.30436
-59	0.06791	1373.22445
-58	0.07173	1370.13677
-57	0.07573	1367.04119
-56	0.07991	1363.93753
-55	0.08426	1360.82565
-54	0.08881	1357.70536
-53	0.09355	1354.57650
-52	0.09849	1351.43889
-51	0.10363	1348.29237
-50	0.10898	1345.13674
-49	0.11455	1341.97183
-48	0.12035	1338.79743
-47	0.12637	1335.61336
-46	0.13263	1332.41942
-45	0.13913	1329.21539
-44	0.14588	1326.00108
-43	0.15288	1322.77627
-42	0.16015	1319.54073
-41	0.16769	1316.29425
-40	0.17550	1313.03658
-39	0.18359	1309.76750
-38	0.19197	1306.48676
-37	0.20065	1303.19412
-36	0.20963	1299.88931
-35	0.21892	1296.57207
-34	0.22853	1293.24214
-33	0.23847	1289.89924
-32	0.24873	1286.54309
-31	0.25934	1283.17340
-30	0.27030	1279.78986
-29	0.28161	1276.39217
-28	0.29328	1272.98003
-27	0.30532	1269.55310
-26	0.31774	1266.11105
-25	0.33055	1262.65355
-24	0.34375	1259.18024
-23	0.35735	1255.69076
-22	0.37137	1252.18476
-21	0.38580	1248.66184
-20	0.40066	1245.12162
-19	0.41595	1241.56371
-18	0.43169	1237.98768
-17	0.44788	1234.39311
-16	0.46453	1230.77958
-15	0.48165	1227.14664
-14	0.49924	1223.49382
-13	0.51733	1219.82066
-12	0.53590	1216.12666
-11	0.55498	1212.41134
-10	0.57458	1208.67417
-9	0.59469	1204.91462
-8	0.61534	1201.13216
-7	0.63652	1197.32622
-6	0.65826	1193.49622
-5	0.68055	1189.64156
-4	0.70341	1185.76164
-3	0.72684	1181.85582
-2	0.75086	1177.92345
-1	0.77548	1173.96386
0	0.80070	1169.97636
1	0.82654	1165.96022
2	0.85300	1161.91471
3	0.88010	1157.83908
4	0.90784	1153.73253
5	0.93623	1149.59425
6	0.96529	1145.42340
7	0.99502	1141.21911
8	1.02544	1136.98049
9	1.05655	1132.70660
10	1.08836	1128.39650
11	1.12089	1124.04917
12	1.15415	1119.66359
13	1.18814	1115.23869
14	1.22288	1110.77335
15	1.25838	1106.26644
16	1.29464	1101.71675
17	1.33169	1097.12303
18	1.36952	1092.48400
19	1.40816	1087.79829
20	1.44761	1083.06451
21	1.48788	1078.28119
22	1.52899	1073.44678
23	1.571	1068.55968
24	1.61376	1063.61820
25	1.65744	1058.62057
26	1.70201	1053.56492
27	1.74747	1048.44929
28	1.79384	1043.27160
29	1.84112	1038.02965
30	1.88934	1032.72112
31	1.93850	1027.34352
32	1.98862	1021.89422
33	2.03971	1016.37040
34	2.09178	1010.76903
35	2.14485	1005.08687
36	2.19893	999.32041
37	2.25404	993.46588
38	2.31018	987.51918
39	2.36738	981.47587
40	2.42565	975.33108
41	2.48499	969.07950
42	2.54544	962.71531
43	2.60700	956.23208
44	2.66970	949.62270
45	2.73354	942.87931
46	2.79854	935.99311
47	2.86473	928.95431
48	2.93211	921.75189
49	3.00072	914.37342
50	3.07056	906.80485
51	3.14166	899.03014
52	3.21404	891.03098
53	3.28771	882.78628
54	3.36271	874.27162
55	3.43906	865.45853
56	3.51677	856.31358
57	3.59588	846.79715
58	3.67641	836.86188
59	3.75838	826.45048
60	3.84184	815.49279
61	3.92680	803.90155
62	4.01330	791.56625
63	4.10138	778.34370
64	4.19107	764.04299
65	4.28241	748.40048
66	4.37544	731.03179
67	4.47021	711.33941
68	4.56677	688.29462
69	4.66515	659.82844
70	4.76534	620.46627
71	4.86691	543.84358

Here is all the data you need to create R410 refrigerant. Refrigerant should be based on water. Good luck !

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

RobDraw — Wed, 22 Sep 2021 23:52:53 GMT

I normally wouldn't endorse such a long post but I think you can say that with a capital "I".

LOL!

Re: Copper R-410A HVAC Refrigeration Pipe/Line-Set Family & MEP Settings

iainsavage — Wed, 22 Sep 2021 23:58:16 GMT

@HVAC-Novice wrote:
I'm not saying modeling and scheduling pipes is bad. But detailing every fitting is overly complex IMHO. YMMV. I never said that I do this. We’re talking about some transitions, not hours of complex modelling.

I also simplify straight pipes and in my model they just look like one long pipe. In practice, it may be multiple 8'sections with fittings.
In the UK this would be acceptable and is what I already do because standard couplings in running lengths of pipe do not need to be enumerated.
I don't model and schedule all the fittings.
In the UK this would not be acceptable because in bills of quantities we are required under standard measurement rules to describe and enumerate every fitting. I did not however say that I model every fitting but what we’re talking about here are some transitions which Revit inserts automatically and then counts for me so why would I not do that?
Obviously someone may benefit from modeling all fittings.

I also change the level of detail depending on if this is done by a contractor (and they have to figure out number of parts), or if that is a project I have to order all material for. I don’t order anything but I have to describe everything in enough accuracy that competing tendering Contractors are all pricing on an equal basis with as little as possible left to chance or interpretation.

Typically the installer will just order special fittings based on what they see or worked out from the submittals.
At tender stage they’ll price those unspecified fittings as £1 and then later say that the actual fitting is £100 and wasn’t sufficiently described in tender documents so they have a valid claim for more money. I’ve been doing this for nearly 40 years, I know what I'm talking about, for UK at least.
This isn't something that needs to be in the model. Chances are, due to some manufacturing change, or using of a different manufacturer or model, they need to use something else anyway. And the installer will change routing somewhat anyway. Again, I need to describe and enumerate items for tender purposes and using the model to help with that is easy. Maybe bends shouldn’t be in the model either? Or tees? Or pipes? We could just have dumb lines - in which case I could use Autocad, maybe even the LT version?

As for the nominal sizes: the actual pipe size (ID) is important for hydronic calculations. Obviously, I’m not stupid. Again, been doing it for nearly 40 years and I went to University before that.

So that should match what is nominal in your country. Incorrect. Maybe for Imperial but not for metric systems. Traditionally steel and iron nominal sizes are based on pipe bore, copper and plastic on outside diameter, but the inside diameter is obviously still the one used for velocity and friction calculation (friction varies with d^5, right?). E.g. 4” is nominally 100mm steel, 108mm copper, 125mm plastic pressure pipe, 110mm plastic soil pipe etc. Revit pipe segments include the ID, OD and ND for that very reason.
Otherwise the velocities are wrong, and with that presssure drop. As above.
For refrigerant, that calculation isn't done in Revit. So you only really need a separate pipe type for scheduling purposes. I totally agree and never said otherwise. I specifically made no comment about the fluid type.

Can we let this drop now? Its getting way off topic over a few transition fittings which I would include and you wouldn’t, so let’s just agree to disagree?